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CURRENTS im the INDIAN OCEAN

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INDIAN OCEAN DIRECTORY. THE SEAMAN a, GUIDE NAVIGATION INDIAN OCEAN AND

CHINA SEA;

INCLUDING

A DESCRIPTION OF THE WINDS, STORMS, TIDES, CURRENTS, &C.; SAILING DIRECTIONS ; A FULL ACCOUNT OF ALL THE ISLANDS; WITH NOTES ON MAKING PASSAGES DURING THE DIFFERENT SEASONS.

WITH NUMEROUS ILLUSTRATIONS, CHARTS AND PLANS.

By W. H. ROSSER, anp J F. IMRAY, F:R.G.8_

| LONDON, E: JAMES IMRAY & SON.

CHART PUBLISHERS AND NAUTICAL BOOKSELLERS, 89 & 102, MINORIES.

1874.

Established 1763.

'

#4 UNLESS OTHERWISE EXPRESSED THE BEARINGS ARE ALL Macnetic; AND THE DISTANCES ARE IN NAUTICAL MILES.

CONTENTS.

N.B. - For List of Lights and Addenda corrected to October lst 1873, see pages vil. and xiii.

PART I.

NOTES ON THE PHYSICAL GEOGRAPHY OF THE INDIAN OCEAN IN ITS APPLICATION TO NAVIGATION.

CHA-POT EiBa-t.

INTRODUCTORY.

The Indian Ocean described 1 - 2.

CHAPTER II.

GENERAL REMARKS ON THE WINDS AND SEASONS.

Winds representing the various Regions of the Globe 3; Theory of the Winds 8; Maury's Theory 5; Dove's Theory 5; Trade Region in the Atlantic 12; Trade- winds in the Pacific 17; Winds of the Indian Ocean, General Remarks 19; Monsoons 19; Summary of Winds in the Monsoon Region 21; the Seasons of the Monsoon Region 22; Winds and Calms in the Indian Ocean 22.

CHAPTER III.

WINDS OF THE INDIAN OCEAN,

The Wind Regiecns, Indian Ocean, classified 23; Explanation of the Chart Dia- grams of the Winds 24; Region of the N.W. Passage Winds 24; S.E. Trade- wind 25; Winds off the Cape and the Eastern Coast of South Africa 235 ; Winds of the Southern Spring in the Western Indian Ocean 29; the South- ern Summer Winds, W. Indian Ocean 32; the Southern Autumn Winds, W. Indian Ocean 35 ; the Southern Winter Winds in the W. Indian Ocean 38; Winds of Central and Eastern Indian Ocean, in Spring 43, in Summer 45, in Autumn 47, in Winter 49; Maury on the Monsoons 50; Meldrum's Meteorological Journal of the Indian Ocean (for March 1853), 53.

iV.

CONTENTS.

CHAPTER IV.

WINDS ALONG THE COAST OF THE INDIAN OCEAN.

South Africa 69; Table Bay 69; False and Simon's Bay 69; Mossel Bay 70;

Algoa Bay 70; Port Natal 70; Delagoa Bay 71; Mozambique Channel, and from C. Corrientes to the Equator 71; Zanzibar 71; Equator to Guard- afui 72; East Coast, Madagascar 72; Reunion 73 ; Mauritius 74; Rodrigues 74; Gulf of Aden 75; Red Sea 76; S.E. Coast of Arabia 80; Gulf of Omman 83; Persian Gulf 83; Bombay and coast to westward 86; West Coast, Hindostan 86; Laccadivh Islands 87; Maldivh Islands 87; Ceylon 87; Gulf of Manaar 88; Bay of Palk 88; Bay of Bengal 88; Weather on the Coromandel coast 89; Head of Bay of Bengal 92; Gales inthe Bay 93; Martaban and Tenasserim, Andaman and Nicobar 94; Strait of Malacca 94; Sumatra, W. Coast 95; Sunda Strait 96; Sunda Strait to Timor Island 96; S. Coast of Java, Sumbawa, &e. 96; N.W. side, Timor Island 97 ; between the Indian Archipelago and Australia 97; Java Sea 97; Banka, Gaspar, and Carimata Straits 100; Borneo 100; Celebes 101; Macassar Strait and Molucca Passage 101; Seas of Celebes and Sulu 102; New Guinea, W. Coast 102 ; Molueca Islands, &c. 102 ; Arafura Sea 102 ; General Remarks on the Malay Archipelago 103; Winds in the China Sea 104; Malacca 106; between Pulo-Timoan and Pulo-Condore 106; Gulf of Siam 106; Cambodia 106; Coast from Siam to Cape Padaran 107; Tong-Quin 107 ; Hainan and South Coast of China 107; Canton River to the Chusan Islands 107 ; Formosa Channel 108; Filippines 108; Palawan 108; Japan 109; Tsugar Strait 110; Ladrones, or Mariana Islands 110.

AUSTRALIA AND TASMANIA.

West and South Coasts of Australia 111; Bass Strait 112; Tasmania 112; Aus-

tralia, East Coast 112; Torres Strait and Coral Sea 113; Sydney 113; Winds of New Zealand 115. -

CHAPTER V.

ON THE USE AND APPLICATION OF METEOROLOGICAL INSTRUMENTS.

Barometer, Thermometer, and Hygrometer - their connexion with the law of

Gyration 123; Mean Movements of Meteorological Instruments 124; Oscillations of Barometer, Thermometer, &e. 126; Position of the Barometer in a Ship 126; Mean height of the Barometer in the Northern and Southern Hemispheres 127, 129; Clouds and their Variations 129; Beaufort's Nota- tion of Wind and Weather 1384; Table showing the Force and Velocity of the Wind 135; Moon's Influence on the Weather 136.

CONTENTS. v.

CHAPTER VI.

HURRICANES OR CYCLONES, AND THE LAW OF STORMS.

Revolving Storms 143; Veering of the Wind-vane 144; the Bearing of the Storm's Centre 144; Rotatory and Progressive Motions of Hurricanes 146; on the Use of a Barometer in a Hurricane or Cyclone 147 ; Meteorological Signs preced- ing a Hurricane 148; the Storm Wave 150; Rules for Trimming a Shipin a Hurricane 150; Hurricanes and Weather in the Indian Ocean 152; Hurricane Seasons in the different Oceans 187; Cyclones in the Hoogly 189.

CHAPTER VII.

TIDES OF THE INDIAN OCEAN, CHINA SEA, AND WESTERN PACIFIC.

To find the Time of High Water 192; Tide-table 193.

CHAPTER VIII.

CURRENTS IN THE INDIAN OCEAN, CHINA SEA, AND WESTERN PACIFIC.

Sketch of Oceanic Currents 206; Currents of the Indian Ocean 210; Equatorial Current 210 ; Mozambique Current 211 ; Counter-currents round Madagascar 211; Agulhas Current 212 ; Counter-current of the South Indian Ocean 2138 ; Australian Current 217; Arabian Sea 217; Gulf of Aden 218 ; Red Sea 219; Persian Gulf 222; West Coast, Hindostan 223; Laccadivhs and Maldivhs 223; Gulf of Manaar 224; Currents round Ceylon 224; Bay of Bengal 226; Malacca Strait 226; West Coast, Sumatra 226; Sunda Strait 226; Currents of the Bay of Bengal during the 8.W. Monsoon 227; Indian Archipelago, S. of the Equator 231; Java Sea 231; Gaspar, Carimata, and Macassar Straits 231; Celebes, Sulu, and Arafura Sea 231; Banda Sea and Molucca Channels 231; Australia, N.W. Coast 232; Currents inthe China Sea during the N.E. and S.W. Monsoons 232; Palawan Passage 233; Gulf of Siam 233; China Coast 234; Pescadores 234; Currents of W. Pacific 234; Equa- torial Currents 234; Kuro-Siwo, or Japan Stream 235; Notes on the Current Charts 241.

CHAPTER IX.

Ice and Icebergs in the Southern Indian Ocean 241 - 254.

CHAPTER X.

On the Specific Gravity and Temperature of the Water of the Indian Ocean 254: Specific Gravity and Temperature of each Square of Ten Degreesin the Indian Ocean 256; Summary 259 ; Specific Gravity and Temperature of each Sqnare of Teun Degrees in the China Sea 260; Saltness of the Ocean 261.

vi. CONTENTS.

CHAPTER XI.

Deep-sea Soundings in the Indian Ocean 263 - 268.

CHAPTER XII.

Whaling Grounds in the Pacific, Atlantic, and Indian Oceans 263 - 268.

CHAPTER XIII.

On the Magnetism of Iron Ships, &c. 268 - 271; Table of the Variation of the Compass in the Indian Ocean and China Sea 272.

PART II.

Sailing Directions for the S. and E. Coasts of Africa; the S.E. Coast of Arabia and Gulf of Aden; the W. Coast of India; the Bay of Bengal; the Islands in the Indian Ocean; the W., N.W., and 8. Coast of Australia and Tasmania 278 - 715. - See Special Index of Places 755 - 786.

Catalogue of reported Rocks and Shoals, Doubtful Dangers, Vigias, &c. 716 - 731.

Notes on making Passages 731 - 753.

For List of Illustrations, Charts, &c., see end of Book, p. 788.

ERRATA.

p. 447, line 25 from top, for 12° 20' read 10° 20'. p- 456, line 2 from top, for 80° 20' read 82° 20'.

LIGHTS.

The following is a complete list of the Lights shown at this date (October 1st, 1873), within the limits of the Navigation described in this work (Indian Ocean Directory). As a full description of them is given in the pages mentioned,

or in the Addenda, it is unnecessary to add more detailed particulars : -

SOUTH AND EAST COAST OF AFRICA.

PAGE. Table Bay .... . =, . Robbenisland.*. Fixed; visible 20 miles 274 a be Green point. Flashing every 10 seconds;

: wistple doomiled: 0.0. 34 ...5 1M a _ Mouillé point.* Fixed red; visible 10 TOUCRME. esos wee os 5 eee 4. . Breakwater. Smallgreenlight ... ,, , South wharf.+ Small green light occasionally ,,

Cape of Good Hope .. . . evolving; bright 12 seconds every minute; VisiblensOr miles. o° *. =. eo ein 2EB Simons Bay . . . , . . . South Roman rock.t Revolving; bright 12 seconds every half-minute ; visible 42 milage oo . ee oo eee Cape ngninas -. , . . « .. I¢zedswvisible 18 miles 9: °, 7 2°... 296 Mossel Bay . . . .. . . Cape St. Blaize. Fiwed red; visible 15 GRA Tse ec eeh eee eee Se

* The lighthouse on Robben island has been coloured red and white in bands, and that on Mouillé point has been painted black and white in bands.

+ The red light formerly shown at North wharf is discontinued.

+ Roman Rock lighthouse has been painted in broad horizontal bands of red and white, in order that it may readily be distinguished when seen against the background of sand.

Vill.

Algoa Bay

' Buffalo River Natal : Inhambane River .

Mozambique Port .

LIGHTS. PAGE Cape Recife. Revolves every minute; visi- ble 15 miles. Sector of red light over GAOIMATETOCKS 40) 50! 1 ol) Geet ares ee Bridge of Baaken river. Small oe green OTL ee 311 Port Elizabeth. Fined: aS 12 cee fed sectors over dangers. . . 311 Bird islands. Fiaved red; visible 14 rnlael See Addenda. jas a ee

East London. Fiawed ; visible 12 miles 329 evolves every minute ; visible 24 miles 337 Barrow East point. Fiwed; visible 10 moles), Sees dca. a Fixed ; visible 14 miles. Building . . 3889

RED SEA AND GULF OF ADEN.

Suez Lightvessel Zafarana Point. . Ras Gharib

Jubal Strait

Dedalus Shoal . Perim Island. . Aden Lightvessel . Ras Marshigh

| WEST COAST

Karachi ae Gulf of Cutch ..

Gulf of Cambay. .

>»?

Dy

Kolaba Point . -

"

9)

Fixed ;-visible 6 miles . .... . S884 Hiveds tyisibled4 miles, 6.6 2. 2 8S 0g; Fixed; visible 20 miles .. . on ee Ashrafi reef. evolves every rete VisiGle: LO-mileg es ef bs i 2S aaa ee Fixed; visible 14 miles ... fe fievolves every minute; visible 29 nae be Fixed; visible 7 miles. . . 389

Fixed; visible 20 miles. Lat. 12° 45! 93"N x

oongua ora' 5S wee. i eet Ose

OF INDIA AND CEYLON.

Manora point, Fiwed; visible 17 miles. 404

Mandavee. fFiwed; visible 10 miles. Uncertain whether now shown . . . 407

Tapti. Fixed; visible 15 miles. See Addenda

Perim island. Fixed ; vinibia ir ance See Addenda . 9 eee eee ok ee

Gogah. Fixed; visible 10 miles (Jn- different light)

Koon Bunder. Fixed; Sabie 10 ied On a mast. ,

Deojugan. Fixed ; ers 10 olen On yt ei a ae ters

Bugwah. Fixed ; visible 10 hits .:

Revolves every 2 minutes; visible 17 miles 410

LIGHTS. ix.

PAGE, Kennery or Kundari Island Fixed; visible 20 miles. See Addenda . 410 Bombay Harbour Outer lightvessel. Revolves (red) every 20 seconds; visible 10 miles . . . 410 = a Inner lightvessel. Fixed; visible 10 miles __,, : - Dolphin shoal. Small light (green and white sectors). Also a small-light at Tourbah pier a Ratna Ghiri . Fixed red ; visible 18 the See, Wehr e 412 Vingorla Two fixed (20 feet apart); visible 9 miles. DeCLADGENd a. k ee i. 2 EI CALS Vingorla Rocks ... . . Fixed; visible 15 miles. See Addenda .,, 108 - (2 pote) 2h =) 1 PRE Aguada 'fort. Revolves every 7 minutes; visible 12 miles . " Sedashigur Bay Outer Oyster rock. Fixed ; 205 fet ales

the sea, visible 25 miles. Supersedes

the temporary light described in text. 414 OOH cn: are . Mixed; visible 12 miles .. . A15 Mangalore ... . White tower. Fixed; 240 feet iauees

high water, visible 11 miles. Lat.

12° 51' N., long. 74° 48' 45" E. Super-

sedes the description in text . Mal EE Cannanore Fixed red (not white as in text); visible ; fad Tasers 20" tore 416 Tellichery On a flagstaff. jinere 112 feet oat

the sea, visible 8 miles. The two lights

described in text are discontinued . iw Calicut . Fixed ; visible 12 miles ayy Cochin . Fixed ; visible 14 miles : Alipey . fievolves every minute ; visible 15 bites 419

Cape Comorin = AF feat oF Manaare.: y..a0.. ass

99 "?

Colombo Point de Galle Great Bassas

Little Bassas Lightvessel .

Trincomadie votes O00 eS. ;

Revolving. In preparation... .. - Tuticorin. Fixed; visible 12 miles . . 443 Paumben passage. Fived; visible 12 miles 442 axed sovisible 18;miles':2 . 1.) }...5. shed Fixed; visible12 miles .. . 427 On the rock. Revolves (red) every "45

seconds; 110 feet above the sea, visible

16 miles. Bellin fog at intervals of

74 seconds. The lightvessel hitherto

moored near the rocks is renoved. . . 481 Flushes every 14 minutes; visible 10 miles 432 Foul point. Jlashes every 80 seconds;

Vinibieikd miles; 1. °F; . 438 Round island. Fixed; visible 10 males -

7?

WEST AND EAST COASTS OF THE BAY OF BENGAL.

Negapatam

Patedowisinle somes. 25055... wv '.. « 2488

xX, LIGHTS.

PAGE Carnicallae era eo et ek ee Pewee; -wisible 8 miléai.'-t 0.5 cel a te dS Pondicherry . . .. . . . Two small temporary lights. Tower rebuilding (1873) . . . . 449 NAdtASNued is eet es, .\ttwed (flashi every 2 Tina ; visible 1tite.:24uhiles'.. st Se eee Pulicat en a Gene. eae. 16a; visible 12.miles.. << ins 4538 Moonapolium .... . . Fixed; visible 16 miles ee Rainy lv Von eee oe oe ae rived; visible 11. miles ..../.... gaa} Masulipatam ... . . .. Indifferent red light. : Cocanada Bay ... . . . Hopeisland. evolves every 10 aocan ie visible 14:miles . .. . . 456 Cocanada. ...... . Fiaed. Uncertain whether now en 5 Deity eh... of. op a awed, visible 12 -milég: °°; 4. Sees

Gopaulpore ... .. . . JFiwed; visible 8 miles. See dddenda . 468 else Omi mein: teil. lily Fixed; wisible:18 miles. -%, -.=iiua eet GL lctehidge ye. eres. ho) Dightvessel, Fiwed .°. 2 ey aes

' Lower Lightvessel. Fived . Me ae toss «i ac El eee Lightvessel. Fixed .

SaugorIsland .... . . Fixed (flash every 20 a Pnibls 15 miles . ' Caycolly an.) <) sie icant eremneible 15 ie : * River Mutlah. . ... . . Lightvessel. Fixed ; visible 7 miles. Caan WOOT. Wylie in 6 'ge eee Bd

Chittagong River . .. . . Two fixed (vertical) ; TaNE 7 raatae See ADDTBA GD 5 cee cl th oes Are Hootubdeah sara ctue + o5lr sled Bb Weed GANISIDIC. Yo miles, Ame. % . Az Akyab. . - . ..... . « . Savageisland. Fixed (flash every inet visible 13 miles. See Addenda i" Alguada Reef... . . . . evolves every minute; visible 18 miles. 478 Krishna Shoal. . . . . . . Fiwed; visible 14 miles. On screw-piles. See AddM@ida.. . s+. 21rh88 China Buckeer .... . . Stevolves every minute; mblo 16 Be: Wee Addenda. ho se lenis oo os Rangoon River . .. . . . Eastern grove. Fiwed; visible 12 miles on screw-piles. See Addenda . Double Island .... .. . Kixed, visible 19 miles Sek. 4 isla Malacca Strait . . .. . . One-Fathom bank lightvessel. Fiwed; visible 10 miles. Lat. 2° 52' 45" N., long. 100° 583' E.

'. 5 Cape Rachada. Fixed; visible 20 pia Lat. 2° 24' 50" N., long. 101° 51' 10" E. Malacca. Fiawed ; visible 12 miles

Benkosiee (Sumatra, W. Coast) Poeloe Tikoes. Fixed; visible 8 miles. Lat. 3° 47' 45" N., long. 102° 19' E. ra 3 Tapu Padrie. Small fixed red light .

ISLANDS

Reunion

" "

Mauritius

Comoro

Andaman Islands

LIGHTS. Xl.

IN THE INDIAN OCEAN.

PAGE. Bel-air point. Fixed; visible 18 miles . 520 St. Denis. Two fiwed (vertical, 12 feet

apart); visible 8 miles St. Paul bay. Fixed; visible 7 eines Port Louis lightvessel. Flashes every 30 seconds; visible 9 miles. See Addenda 528 Cannonier point. Fixed; visible 10 miles. Red sector over dangers . . . . 5386 Flat island. evolves every mittee visible 25 miles : Grand port. Fiwed; visible 16 ne . 539 Mayotte. Fixed (harbour light). Un-

"

certain whether exhibited . . . . . 868 Great Cocoisland. Fiaed; visible 22 miles. See Addendacs < "Ras x, (Oe Pees

WEST AND SOUTH COAST OF AUSTRALIA.

Rottnest Island Swan River Breaksea Island .

Princess Royal Harbour .

Spencer Gulf Kangaroo Island .

Cape Willoughby Troubridge Shoal

Port Wakefield

Port Adelaide . ; Adelaide Pilot Station . Holdfast Bay .

Cape Jervis

Cape Bernouilli or J ain

Cape Northumberland .

Portland Bay .

Fievolves every minute; visible 20 miles 656 Arthur head. F wed; visible 14 miles . 658 Fixed; visible 25 miles . Aya! King point. Fixed ; visible 10 miles . re Tipara lightvessel. Fixed; visible 10 miles 673 Cape Borda. evolves (red and white) every 30 seconds; visible red 15 and white 30 miles ... itn, tote mae Oe Revolves every 13 minutes; Hula 24 miles 683 Intermittent (visible 24 s. every minute) ; vistble l4mileg ¢7y p02 427.) . » ey GBA Small fixed light. See Addenda Fived; visible 10 miles. See Addenda . 685 Fixed red; visible 6 miles . Fiaxed green; visible 6 miles . =, Ve Fixed; visible 13 miles. See VeaPey: + OOO Revolves every 30 seconds; visible 16 miles es . 691 evolves every AGE ie 2 green oH visible 18 (white), 15 cau and 8 (green) miles) . . . . 692 A fixed red light near Pye hill, visible 14 miles; anda small green TOPO TOtLY ce sh SL hs. 3 ORE

"»

Xil.

Port Fairy Warrnambool . Cape Otway Cape Schanck .

Port Western .

Wilson Promontory

Port Phillip (See Addenda) .

Port Albert .

Cape Howe .

LIGHTS.

. Rabbit island. Fiwed (flash red every

3 minutes). Also a small Stee light on jetty

Two fixed lights on hill i in fr ant of town ; upper white, lower red. Also a fixed green light on jetty. See Addenda

Revolves every minute; visible 24 miles .

Fixed (flash every 2 minutes); visible 23 miles . ever? TSS oer

Fived (white and red); visible 4 miles See Addenda

Fixed; visible 24 miles .

Lonsdale point. Fiaved (green maa ra sectors) ; visible 10 miles .

Shortland bluff. Two lights. oes fixed white; visible 17 miles. Lower, fixed (white and red sree! visible 14 and 10 miles :

Queenscliff jetty. A small green light

PAGE.

695

696

696

698

699 699

697

697 702

Swan spit. Sixed (red and white sectors) ;

visible 8 miles . eM seh = West Channel leg leneed: Two fixed; visible 10 miles Sree. ae Schnapper point. Fixed; visible 10 mile Point Gellibrand lightvessel. Fiwed (flash every 380 seconds); visible 10 miles. Also, other small lights (red, green and white)... ee eee. ET Uae Fixed (flash pa 3 ate visible 11 miles. See Addenda Gabo island. Fixed; visible 22 ree See Addenda

TASMANIA AND ISLANDS ADJACENT,

King Island Kent Islands .

Chappell Islands Swan Island

Dalrymple .

Hobarton

" "

Cape Bruny.

Cape Wickham. Fizaed; visible 24 miles

698

703 s 705

704

709

710

Deal island. evolves every 100 seconds ;

visible 36 miles ' Goose island. Fixed; eshte od Eipe ; Revolves every minute; visible 14 miles . fievolves every 100 seconds; visible 15 miles Iron Pot rock. Fised: visible 10 hile Pier-head. Small red light fevolves every 100 seconds; visible 22 miles

INDIAN OCEAN DIRECTORY.

[ADDENDA to OCTOBER Ist, 1873.]

' ALFRED DOCKS (Table Bay). - It appears by recent (1870) intelligence from Cape Town that the charge on ships in the New Alfred docks is 6d. per ton register for the first month, and 1d. per ton, against 5s. in the roadstead. There is also the saving of time to be noticed. One ship discharged 2000 bags of coffee and ballasted in 24 hours, and another delivered 6000 bags of rice and ballasted in 48 hours. Water 3s. per ton. There is a good patent slip and a steamer already on it. Arrangements are also in progress for a graving dock. The dock is still incomplete, the entrance from sea, roads, and approaches not yet finished; but there is 17 feet water at lowest spring tides in the entrance. The rise of tide is 5 to 6 feet. In the dock the water is 24 feet at low tides, with the facility of discharging alongside a quay in perfect safety. There are no light or other dues on shipping visiting here, except the 6d. per ton if they use the dock. Pages 273 - 282.

DASSEN ISLAND. - The following information is furnished by Navigating Lieutenant W. E. Archdeacon, Admiralty Surveyor ; -

Two sunken rocks with respectively 54 and 63 fathoms at low water, and on which the sea breaks heavily during and after bad weather, lie 3} miles from the south-western shore of Dassen island.

The rocks are N.W. 4 W. and S.E. 3 E. from each other, distant 14 miles, with deep water between. The western rock, with 54 fathoms on it, is steep-to on the western side, 20 fathoms having been found at a distance of one cable. On its eastern side the bottom is very irregular for nearly a mile, the depths varying from 10 to 20 fathoms, causing a confused and dangerous sea in bad weather. From this rock the southern point of Dassen island (which is the highest) bears N.E. by E. 4 E. 33 miles, and the conspicuous high sandhill at Bock Riviere S.E.4 5S. The eastern rock with 63 fathoms on the shoalest part has depths exceeding 20 fathoms at a cable distance all round: from it the southern point of Dassen island bears N.E. 4 N. 3} miles, and the sandhill at Bock Riviere §.E.35. Variation 29° 45' W. (1869.) Page 278.

CAPE OF GOOD HOPE. - Heavy breakers, during bad weather, having been reported by the keepers of the Cape of Good Hope lighthouse in a north-westerly

Xly. ADDENDA.

direction, the following is the result of an examination made by the direction of the Commodore at Simons bay : -

The breakers are on a rocky ledge, about a mile in extent, and from 13 to 2 miles from the shore, having 103 fathoms on its shoalest part (near a depth of 11 fathoms already marked on the chart), with soundings gradually increasing to 20 fathoms on its outer edge, and with 18 fathoms between the ledge and the coast.

From it the following bearings were observed : - Cape of Good Hope Hghthonse S.E. 3 S., 64 miles; Polesberg, E. by 8.; and Slangkop point, N. by E.3E., 10 ae

This rocky bank lies somewhat in the fairway for vessels passing round the coast to and from Table bay, and asin heavy southerly gales a continuous line of breakers has been observed to extend between this ledge and the shore vessels are accordingly cautioned not to approach this part of the coast in bad weather. (1868). Page 285.

In reference to the following reported bank of soundings, it should be stated that the neighbourhood of the bank was closely examined by H.M.S. Petre/ in 1868, and bottom touched at 200 fathoms on the assigned spot, and soundings of not less than 130 fathoms obtained within a radius of 5 miles of it; hence the bank, if it exists, must be in a different position than that assigned to it.

"The Spanish merchant vessel Justa, on her voyage from Macao to Havana, is said to have discovered a patch of shoal ground at about 5 leagues south-west- ward from the Cape of Good Hope.

The shoal bank, on which several casts of the lead were taken during a calm, 'had from 153 to 13 fathoms, rocky bottom; from the latter depth the water suddenly deepened and no bottom could be found.

At the time of the first sounding in 153 fathoms the Cape of Good Hope light- house bore E. by N. (N. 49° E. true), and the assumed distance from the cape was 16 miles. This bearing and distance would place the bank in lat. 34° 311' S., long. 18° 153' EK." (1867). Page 286.

The following information respecting shoal ground between the Cape of Good Hope and the Bellows and Anvil rocks is by Lieut. W. EK. Archdeacon : -

Three pinnacle rocks with 43 and 5 fathoms on them have been found to lie between the Cape point and the Anvil rock, rendering that passage, which has hitherto been considered free from danger, unavailable for ships of large draught, or even for small vessels in bad weather.

The inner danger, with 43 fathoms over it, and 10 fathoms all round, lies S.S.E. 4 E., 3 cables from the Dias rock off Cape point.

The two outer rocks, having 5 fathoms over them, are about a } of a mile apart, with 10 fathoms between, and all round. 'The western one lies S. by E., 8 cables, and the eastern S.S.E. } E., 9 cables, from the Dias rock; the latter danger bearing from the Anyil rock N.N.W., distant about 4 cables. Variation 29° 40' W. (1869). Page 287.

COAST OF CAPE coLtony. - In consequence of the disastrous wrecks that have recently taken place in the neighbourhood of Struys point near cape Agulhas, and of the reported inaccuracies of the existing charts and sailing directions, a close examination of the coast and outlying dangers from Struys point to Hoap point, including the Atlas reef, has been made by Navigating Lieutenant, W. E.

ADDENDA. Xv.

Archdeacon, of the Admiralty Survey, in H.M.S. Dido, Captain William C. Chapman, R.N. The Hydrographic Office publishes the following as the result of the survey : -

Struys Point. - On the 8th of March, 1872, the Dido arrived off Struys point and was anchored in 23 fathoms, with the beacon which is built on that point close to the high water mark of spring tides, bearing N.N.W. distant 2:9 miles.*

From Struys point a chain of reefs extends a distance of 1? miles to the S.S.E. On the outer detached rock which is locally named the Blinder, 18 feet at low water was found, with 4 to 6 fathoms close to the rock, and 7 to 9 fathoms extending a distance of 4 cables to seaward. This Blinder rock (in close proximity to which Lieutenant Archdeacon was placed by the fishermen of the district) lies 8.S.E., distant 1:8 miles from the beacon on Struys point. North- ward, in the direction of Struys point, 3 cables from the Blinder rock is the Bulldog or Saxon reef, with 12 feet on it at low water, and 8 fathoms close to, but with shoal ground (about 4 fathoms) between it and the Blinder rock. Between the Bulldog reef and Struys point, the chain of reefs is shoal and ex- tensive, with boat passages between in fine weather. In standing towards these dangers from the south-east, the Agulhas light will become invisible on a bearing of W. + N., that line of direction passing more than 3 cables to the southward of the Blinder reef.

The experienced fishermen of the locality who assisted Navigating Lieutenant Archdeacon in his examination, all agreed as to the Blinder rock being the outer danger from Struys point ; from this fact and the close examination made at the time, as also from observations made during a south-west gale ; - which afforded a good opportnnity for deciding the extent of the breakers, - it is certain that the limits of the dangers extending from Struys point as above described are accurately defined, and that there is no foundation for the report that these reefs are found at a distance of 6 miles from the shore.+

The fishermen also state that the whole of this line of coast, from Struys point towards Martha point and to the eastward, is fringed with a series of reefs, with depths varying from 4 to 6 fathoms which break in heavy weather; there are passages between the reefs and deeper water inside of them.

The wind freshening from the south-west after the above examination, the Dido weighed and found good shelter to the eastward of Struys point where she anchored in 11 fathoms: the beacon on the point bearing West distant 13 miles.

The Atlas Reef was next examined, and found to lie 1:4 miles from the coast with Struys point beacon bearing W. 4S. distant nearly 7 miles. Although

* A stone beacon 34 feet high, 10 feet square at base, and 6 feet at top, surmounted by a copper ball 4 feet in diameter, has been erected on Struys point. The beacon ig coloured red to seaward, with red and white bands on the east and west sides, and is built about 2 feet above high water spring tides.

+ Navigating Lieutenant Archdeacon remarks, that it is certain that the vessels which have been recently wrecked in this locality struck on, or in the vicinity of the Bulldog or Saxon reef. In the case of the Benefactress it was stated that the lighthouse was invisible, and in that of the Saxon that they opened the light a few minutes after hauling to the southward to get clear of the reef on which the vessel had struck; which would agree with the inshore limit of the light on cape Agulhas, as given in the charts.

Xvi. ADDENDA.

assisted by fishermen of the locality, the reported shoalest part of 3 fathoms was not found, nothing less than 5 fathoms being obtained ; the extent of the Atlas reef was however determined, and another rock with 4 fathoms named the Miles Barton discovered at a distance of about 6 cables from the Atlas reef in the direction of Struys point.

The bearing of the conical peak (N.W. 4 W.) and distance of Struys point (7 miles) as given in the African Pilot, page 43, nearly agrees with the position of the Atlas reef as now determined.

- In the third paragraph of page 43 of the African Pilot, vessels are cautioned not to approach this part of the coast nearer than 7 miles, at which distance they will find 20 fathoms: Lieutenant Archdeacon recommends, particularly when westward of the Atlas reef, that vessels should not under any circumstances, at - night, approach within a depth of 40 fathoms.

St. Francis Bay. - The Cockscomb mountain given as a distinguishing mark for St. Francis bay, bears N.N.E., distant 38 miles from cape St. Francis, instead of N.E. } N., distant 30 miles as stated in the African Pilot, page 55.

St. John River. - Bismarck rock on which the steam-vessel Bismarck struck on 29th December, 1871, and described in Notice to Mariners, No. 24, of 1872, has been examined by Navigating Lieutenant Archdeacon, and found to lie one- sixth instead of three-quarters of a mile from the shore. This rock has not more than 6 feet on it at low water springs, with deep water between it and the shore. From the Bismarck rock cape Hermes bears W. 3 S. distant 2°6 miles.

Caution. - The coast between the Bashee and Umcomass rivers is fringed with outlying rocks for a distance varying from one to 5 cables from the shore. Variation 80° 10' W. (1872.) Page 297 - 332.

CAPE RECIFE, - The lighthouse on the cape now shows a ray of red light over Roman or Dispatch rock, in the arc from it of N. 39° E. to N. 12° E. (27°). Vessels bound to Port Elizabeth, after passing cape Recife, should not enter this red ray until the Harbour light on the hill (which when first seen is red) is seen bearing N.W., but as the southern limit of the Harbour light passes only 2 cables northward of Roman rock, it is recommended that a course for the anchorage should not be shaped until the red ray from the Harbour light is passed and the white light seen bearing N.W. by W. Pages 309-310. :

ALGOA BAY. - The Harbour Master at Algoa bay has given notice of the existence of a rocky shoal lying to the southward of the anchorage in Algoa bay, 8 cables from the shore.

The shoal, named Strutts reef, is about 50 square yards in extent, and has. 15 feet water on it at low water springs. The shoal lies with the water pipe and reservoir house in a line with the two southernmost houses of the town bearing W. 4N.; Scotch church spire in a line with the square tower of St. Mary's church N.W.; Bird rock S.S.E.; Harbour lighthouse N.W. 4 W.

Clearing Marks. - The tower of the Mosque (which is red) open of the north end of the breakwater, and the tower of the Gray institute open to the northward of the harbour lighthouse, clears the shoal in 25 feet water. Page 310.

BIRD ISLAND - A new lighthouse has been erected on Bird island, from which a fiaed red light is exhibited, to supersede the two white lights hitherto shown.

ADDENDA. XVil.

The new red light is 80 feet above the sea, and visible all round the horizon at the distance of 14 miles.

The new tower is stone coloured, showing a large ornamental cross on its north and south faces; but onlya circular aperture, in the centre of the tower, is shown on its east and west sides; its site is so near the old building (100 feet due North) as to produce no appreciable differences in the bearings and distances already given. The new building, 72 feet from base to vane being longer and higher than the old one, will be more conspicuous in daylight than heretofore. The old building will be removed.

Caution. - Ships passing inside the island during night, particularly steam- vessels, are recommended to keep nearer to the mainland than the group, as the Jand is higher and more readily discerned, and the roar of the surf (which is con- stant) is more distinctly heard than the breakers on the rocky reefs of the group. The lead will always indicate a too near approach to the main shore, and 11 to 12 fathoms is a safe depth in passing the group ; but a wider berth must be given in passing point Padrone, off which shallow ground extends for a mile. In passing outside the group no vessel should approach within 3 miles of the light, as no advantage is gained by it, and the currents, though not generally strong, are uncertain and irregular, both in force and direction, in the vicinity of the group. Page 322.

WATAL, - A white conical tower 81 feet. high has been erected on the bluff at the east side of the entrance to the harbour. It shows a light revolving every minute at 292 feet above the sea, visible 24 miles. The arc illuminated is 239° (from North eastward and southward to S. 59° W.).

As this light is not visible from Aliwal shoal, which is 25 miles S. 53° W. from the lighthouse, vessels approaching the harbour from southward and westward should not approach the shore nearer than 4 miles, nor get into a less depth than 40 fathoms. 'The lead should be hove freely until the light is well made out from the deck, when they may stand in until it bears N. 59° K.; this bearing will keep them outside all known dangers until abreast Umlazi river which is about 93 miles southward from the lighthouse. As the land then trends more to east- ward, the light must be kept more to northward, and the shore must have a berth of at least a mile; when the light bears about W.N.W., they can haul in north- ward for the anchorage. The anchorage is in from 8} to 10 fathoms at about a mile N.E. to N.E. } N. from the lighthouse. Pages 335-337.

INHAMBANE RIVER. - <A lighthouse painted white has been erected on Barrow hill, south side of entrance to Inhambane river. It bears a fixed light at an elevation Gf 80 feet above the sea level and visible 14 miles. The light is shown seaward from 8.E.:S. to W. by N.4N. Position, lat. 23° 45' 30" S., long. 35° 33' 10" KE. Page 388.

DARRA SALAAM ,. - The following description of the harbour of Darra Salaam, on the East Coast of Africa, is by Commander Richard Bradshaw, commanding H.M.S. Star, 1867,: -

The harbour of Darra Salaam is situated on the main land 41 miles South from Zanzibar, and is approximately in lat. 6° 49' S., long. 39° 22' E.; it lies in the bight of a bay formed by Motumoko point, 12 miles N.W. by W. 4 W. from the latter.

On approaching the harbour from Zanzibar, and after passing Choomby

XYlil. ADDENDA.

island, the course is S. by E. } E. to avoid the Tom shoal, which latter will be seen breaking about 2 miles distant. The same course should be preserved until Sindo island is clearly made out, bearing about S. by W. } W., then steer to keep Sindo island on the port side, passing it about three-quarters of a mile distant, the Goonja islands being kept on the'starboard side. By this time the coast, whichis low, will be clearly seen, and between two red cliffs, each about 80 feet high, is the harbour of Darra Salaam, the entrance being nearly opposite the East cliff.

Outside the entrance there is good anchorage under Sindo island. If proceed- ing into the harbour, two buoys will be seen nearly half a mile distant from the East cliff; they are placed on the edge of the reefs extending from the West and East cliffs, in 34 fathoms at low water, 17 cables apart, and bearing W. by S. 38. and EX. by N. ¢ N. from each other. In approaching the buoys, a vessel should not get into less than 5 fathoms; it deepens between them to 9 and 10 fathoms ; immediately after passing the buoys, alter course quickly to S.W. by W. } W., keeping the inner point (a point forming the left extreme of a long sandy beach) a little on the starboard bow; not less than 5 fathoms should be struck in this channel. On rounding the inner point a large sheet of water opens to the view, in any part of which a vessel may anchor in 5 or 6 fathoms.

The entrance channel is about a mile long; it is narrow but strait, with coral reefs on either side; all dangers may be seen from half-way up the lower rigging. The harbour is capable of holding a great number of ships of moderate tonnage ; the Sultan of Zanzibar with his Heet was at anchor during the visit of H.M.S. Star.

It was observed that a new palace was nearly completed, and a town laid out, the allotments of which were nearly all taken. The jungle was being rapidly cleared, and the soil is said to be excellent. It is thought that this port will supersede Quiloa as the domestic slave depot of the Sultan, the caravans from the interior altering their route for it on account of its proximity to Zanzibar. Quiloa being 160 miles distant, the difference is a great consideration to the dhows conveying slaves.

Tides. - It is high water, full and change, at 4h. 0m.; springs rise 12 feet.

Oaution. - A dangerous bank of coral lies 5 miles N.N.E. from the buoys; it was passed over in 3 fathoms, about an hour after low water.

The following description of a shoal patch to the northward of the harbour of Darra Salaam, south of Zanzibar, is from Commander George L. Sullivan of H.M.S. Daphne : -

This shoal, on which there is 18 feet water, and 5 fathoms on either side, was discovered in H.M.S. Daphne while on her passage from Zanzibar to Darra Salaam. From the shoal Pinda island bears S.E., the inner Sindo island S. 3 E., and the centre of the red or Kast cliff of the entrance to the harbour of Darra Salaam, S. by W. distant 44 miles.

Commander Sullivan gives the following directions for approaching Darra Salaam from the northward: - Keep Sindo island well on the starboard bow until the centre of the East clif (red) bears 8S. by W. 3? W., then steer for it on this bearing, which will lead to the buoys at the entrance; there should be nothing less than 5 fathoms on this line of bearing.

Note. - The island marked on the chart of this part of the coast as the South Goonja does not exist; what has been hitherto taken for this island is a part of

ADDENDA. xix.

the main land. There are thus only two Goonja islands. Variation 10° 10' W. (1869). Page 340.

LATHAM BANK. - The ship Hydrabad has lately (1869) been lost on this bank; she had been chartered at Jedda for Zanzibar. Mr. Kirk H.M. consul and political agent, says, - Finding themselves close to the Latham shoal at night they let go the anchor. On getting under way at daybreak the ship drifted on the reef, which lay to leeward, and broke to pieces in the surf. Sheik Suliman Bin Ali, the Sultan's Vizier, left in charge of the government during His Highness's absence, at once ordered His Highness's steam yacht Star to be got ready, and he and I started during the night to rescue those that remained. Having safely passed by moonlight through the reefs and sand banks near Zanzibar. we reached Latham shoal at 1 p.m. of the following day. A more dangerous or desolate spot I have never seen. It is a solitary coral knoll, about 300 yards in length, rising about 10 feet above the sea level at high water, and out of sight of land, No tree or blade of grass is to be seen on it. This barren islet is covered with sand and coarse guano from the sea fowl that are to be seen rising in dark clouds from time to time. Fortunately for the mariner the lead gives warning of this danger at a distance of several miles, and on the surround- ing bank fair anchorage may be found. But the currents here are very strong, running always northwards, though with variable force and direction. Having anchored on the lee side of the reef, in 6 fathoms, at a distance of 3 mile from the breakers, we at once commenced to take off the survivors. This was a slow process, which was not ended before 8 p.m., as the boat could not reach the shore, and the shipwrecked people had to be carried off one by one through the surf. Page 341.

ZANZIBAR. - The following information from the remark book of Lieut. H. C. Taylor, R.N., of H.M.S. Cossack November 1869, has been published by the Hydrographic office : -

The Northerly Current in the vicinity of Latham island was experienced by the Cossack, setting her, in November 1869, to the northward, against a north- east breeze, about 32 miles in 7} hours.

Zanzibar Harbour. - Lieutenaut Taylor recommends lying at single anchor at a short distance off shore in preference to mooring close in, and thus avoid the fetid and pestilential odours from the town, which at this season of the year (November) are not only disagreeable but unhealthy.

To the west and north-west of Bawy island the sea appeared to be very foul, numerous patches of coral showing in all directions.

Tumbat Island. - The Svuth extreme of Tumbat is in Lat. 5° 52' 30" S., long. 89° 14' 48" E.

There is a passage between Benoth, the small island lying off the eastern side of Tumbat, and Zanzibar, but none exists between Tumbat and Benvth. The reef from Benoth island extends to the north-west and surrounds Moina island, connecting it with Tumbat. The shoal shown on the chart as lying to the north-east of Tumbat could not be found.

Vessels anchoring olf Tumbat island should not close the two southern poiuts, which lie nearly east and west of each other. Variation 10° W. (1870). Page 341. |

b 2

XX. ADDENDA.

EAST COAST of AFRICA, - The following remarks on the Hast Coast of Africa, which is at present but imperfectly surveyed, are from recent observa- tions of Sir H. Bartle Frere, K.C.B., who has drawn attention to the importance of an early survey; itis not improbable that a considerable trade may soon spring up with the whole of the Hast Coast of Africa : -

I will briefly describe the coast as it appeared to us between Ras Haftn, the most easterly promontory ofAfrica, and Mozambique.

Ras Haftin itself may be described as the crater of an extinct volcanic ex- plosion, which has raised the limestone beds to a height of about 400 feet above the sea-level, not in detached peaks, but with a nearly uniform surface towards the east, the broken strata dipping inwards towards the centre of the crater. open on the western side towards the mainland, to which it is joined by a spit of Sand. The bays north and south afford good anchorage and shelter, according to the monsoon, at all times of the year. T'rom this headland the coast, for a distance of many miles, is a uniform rocky wall, with apparently few indentations, and no mountains in the interior visible from the sea. About Magadoxa the coast becomes very sandy, with occasionally rocky bluffs as far south as the Juba river; a fringe of coral reef and islets here begins to mask the coast; south of Melinda the sand-hills cease, and the coast assumes that aspect which it bears with little variation as far south as Mozambique.

The appearance of this Somali and Galla coast is singularly uninviting, seen as it usually is during the dry season (for during the rains vessels keep far off the shore) ; there are no traces of cultivation or pasturage, and at first sight all appears utterly barren and almost uninhabited. A nearer approach to the shore shows, however, numerous paths, parallel to the coast line, indicative of con- siderable transit along the shore. Smoke-signals by day and fire-beacons by night are seen giving notice along the coast that a vessel is in sight; and if the vessel approaches near the land, as if about to send boats ashore, groups of natives, generally armed, are seen collecting from all quarters and coming down over the sand-hills. The fact is that, as described by Dr. Kirk, the barren hills of the coast generally mask a country of great natural fertility, supporting a con- siderable population of pastoral tribes, with much cultivation in parts.

The few towns, such.as Magadoxa, Merka, and Brava, through which the Somalis of the East Coast communicate with the outer world, are evidently centres of considerable commercial activity. The more opulent of the permanent inhabitants live in substantial masonry houses, which give to the towns, when geen from the sea, a very imposing appearance. The town is always capable of defence against the surrounding tribes, and strangers, who are not inhabitants, are usually turned out of the town at sunset.

Cattle-hides, orchilla-weed, small timber, and oil-seeds, and a few small horses, donkeys, and camels, are at present the principal exports, with a few articles, such as ivory and ostrich-feathers, from the far interior.

Between Melinda and Mombas the coast changes from the uniform barren sands and rocky ridges of the Somali coast, and assumes the typical features of the coral-fringed coast of East Africa. From Melinda to Mozambique the general features of the immediate vicinity of the seashore are those of raised coral-reefs, or sand and gravel beaches. Seaward the coast is fringed with a perfect labyrinth of coral reefs and islets, which, according to circumstances of

ADDENDA. XXi.

weather and current, prove the greatest dangers or afford the greatest facilities to the mariner. Woe to the large sailing vessel which finds herself set by the current or driven by the wind into the labyrinth, the intricacies and dangers of | which are very imperfectly shown on his chart. The water between the reefs is often too deep to allow of anchoring, even close to the shore, and unless the wind be fair and daylight favourable, no prudent mariner will take a sailing ship near dangers which are more frequently just under than above the surface of the water.

But to the Arab mariner who knows the coast and its dangers by long practice, and who never willingly sails except at the season of regular steady winds, and always, if possible, anchors at night, the coral-reef fringed coast affords peculiar facilities. There is always smooth water inside the reefs, however hard it may blow outside. In fine weather, with the sun at the navigator's back, the reefs are easily seen by the colour of the water; when it blows they are marked by the break of the sea on their edges, and there are generally frequent openings, with deep-water channels, in the line of the reefs, giving easy access from one set of channels to another. The Arab dhows usually, if they can, navigate these seas in company, two or more together. and as they rarely attempt to beat against a wind, or to sail on after dark, and as time is to them of little con- sequence, they meet with disaster more rarely than might be expected of such frail barks, in seas so thickly studded with reefs and sand-banks. The beauty of the low coral islands has been often described.

The orchilla-weed has long been an article of export in large quantities, and though now somewhat superseded by the weed procured in South America, there are probably other dye-weeds and vegetable products useful in dyeing. Palm- nut oil has been already added to the commercial exports of East Africa. We were informed that it was formerly common in Zanzibar, but had been cut down in clearing the jungle. Madagascar appears to abound in valuable cabinet woods, ebony, &¢. Cotton appears to grow wild on many parts of the coast. Many parts of the coast are obviously well adapted for the growth of coffee, and a list of oil-seeds which are now exported may be considerably augmented by fresh discoveries.

It is a curious fact that the mortality among European crews on this coast his greatly decreased since the ships have been restricted, as far as possible, to the use of distilled water. . Pages 341 - 348.

MINOW ISLANDS. - A sunken danger has been discovered by the grounding of H:M.S. Daphne, while cruizing in September 1868, among the Minow islands, in the northern part of the Mozambique channel. 'This danger lies in the southern part of the group, directly between Mount and Coral islands; the peak of the former island bearing from the rock 8.4. and distant about 8 cables. On examination it was found to be a small detached coral patch, with 2 fathoms on the shoalest part, and 7 fathoms close to. Page 348.

COMORO ISLANDS. - The following information relative to the Comoro islands, is from the remark book of Lieut. H. C. Taylor, R.N., of H.M.S. Coss ick, November 1869, and has been published by the Hydrographic Office : -

Johanna Road. - The beacon erected to mark the anchorage ground in Johanna road is difficult to see until quite close in, as it is partly overgrown with

XXxil. ADDENDA.

bushes, and one of the numerous huts near the town is also built close alongside it. <A better mark is a bluff point of rock, lying about 400 yards westward of the beacon, which has a large whitewashed target on its face used by men-of-war.

Pomony Harbour. - At present there are no beacons at Pomony, and the buoy on the Middle ground is also gone. A beacon is much wanted to mark the centre line of the harbour. The anchorage is limited, and vessels likely to remain at Pomony should keep the factory chimney on a N.E. by E. bearing, and not anchor in less than 12 fathoms.

Current. - The Cossack during her passage from Zanzibar to Johanna in December 1869, experienced the full force of the westerly current which flows past Comoro island. The day before making that island a course was shaped to pass 80 miles to windward of it ; the Cossack experienced 40 miles current then, and 70 miles on the following day, setting in a direction nearly west, and forcing the ship to leeward of the islands.

The French ship Persévérance is reported to have touched the bottom on a bank westward of the island of Comoro. The bearings taken were, the north- west point of the island N. 40° E. and the south point of the island S. 58° E. ; - the depth was about 17 feet. The bank was apparently of considerable extent. (1867). Pages 3538 - 355.

RED SEA - Suez Bay. - A sunken rock has been discovered in the fairway of the entrance to Suez bay. :

The rock is a pinnacle rock with only 13 feet water on it at low water springs, and lies 8. 3 W. 1,% miles from the lightvessel, and §.S.E. 3 E. 1,9, miles from Kal' ah Kebireh beacon.

To avoid the danger by day, vessels should keep the lightvessel on with the westernmost minaret of the town of Suez. By night, a N. by E. bearing of the light will lead to the westward of the danger.

A small red buoy has been temporarily placed on the danger. Variation 5° W. (1870).

Gulf of Suez, - The following description of the extension of the reef to sea- ward from Ras Sherateeb, on the eastern coast of the Gulf of Suez (northward of Tur harbour) as resulting from the survey now in progress, has been received by - the Hydrographic Office from Captain G 8S. Nares, R.N., H.M. Surveying vessel Shearwater, 1872 : -

A narrow ridge of rocks with from 5 to 3} fathoms on it, has been found to extend 6} miles from the land of Ras Sherateeb, or about 4 miles seaward from tke encircling reef as shown in the present charts in that neighbourhood, and known as the Shab Khoswan. This shoal ground narrows the channel at thig part of the Gulf of Suez to 8 miles.

From the western extreme of the shoal water on this rocky ridge, the Ras Gharib lighthouse bears S. 4 W., distant 14 miles.

The Asses ears, a remarkable double boulder rock on the Jehan hills, (which are 10 miles to the southward of Ras Sherateeb,) when in one with Jebel Hooswah, the highest hill on the coast range 3} miles to the south-east of the ~ Asses ears, and bearing S.E. by E. 3 E., will lead clear of the west end of the shoal ground.

The approximate geographical position of the western extremity of this narrow ridge of rocks is lat. 28° 35' N., long. 38° 5' E, Variation 5° 20' W. (1872.)

ADDENDA. XXiil.

Strait of Jubai. - A small sunken rock, lies nearly in the middle of the bay, recommended as an excellent anchorage during north-west winds, on the south- west side of Shadwan island. It lies about 54 cables from the shore, with the extreme of the low sandy point forming the western side of bay bearing N.W. by W. + W., distant 84 cables, and is thus nearly in the middle of the anchorage bay.

This rock can be seen with a proper look-out, having only 2 or 3 feet on it, or nearly awash. The depth is 5 fathoms inshore of the rock, and 6 and 7 fathoms on its southern side. Variation 5° 40' W. (1871).

Jubal Strait Bank. - H.M.S. Newport, engaged in the survey of the northern part of the Red Sea, has found shoal ground of 18 and 24 feet on the bank in Jubal strait (Jubal strait bank), lying midway between Tur and Shukhair, hitherto considered to have not less than a general depth of 5 or 6 fathoms water on it, with an assumed shoal of 21 feet.

The shoal coral patch of 18 feet sounded on by H.M.S8. Newport, is in lat. 28° 10' 15" N., long. 33° 28' 40" E.; and 2 miles to the N.W. of this, is another shoal of 24 feet: in the aerate ta tat of these shoals, several patches with from 7 to 10 fathoms were found.

There are no outlying dangers off the neighbouring coast of Ras Shukhair, which may be approached te a distance of one mile.

Iocha. - A shoal patch, hitherto unknown, lying a league to the westward of the shoal ground off the town of Mocha, and near the fairway track of shipping bound up or down the Red Sea, has been found by the Master of the S.S. Priam on her voyage down the Red Sea.

The shoal, is a bank of white sand, about half a cable long and 30 feet broad; it has 182 feet on its central part with 11 fathoms at either end.

From the shoal, the north end of Mocha bore E.N.E., and Zee hill S.E. 48.

These bearings place it about 7 miles from the land. Variation 33° W. (1870).

Brothers Islands. - Reliable information has been received, that the position in latitude hitherto assigned to the*islands known as "The Brothers" in the chart of the Red Sea is about 4 miles in error.

The latitude of the northern island is approximately in 26° 17' 30" N. instead of 26° 22' N. ;

Also, the sailing directions, following Moresby, make them 60 feet high: Captain Lapierre of the F.I.N. gives the height from 10 to 13 feet. (1870).

Perim Island. - The Commander of the steam vessel /vora, states in passing the north-west side of Perim island, the ship grounded in 18 feet water, three- quarters of a mile from the shore, and remained there upwards of 48 hours.

From the position in which the ship struck, the lighthouse bore S.K.}E., and the west point of the island S. by W. 4 W. nearly a mile. The water gradually shcaled towards the BuOre, but increased to 5 and 7 fathoms 1 cable to seaward.

Note. - Mariners are cautioned in approaching this locality, as the extent of the shoal ground is yet unknown. Variation 4° W. (1871).

Azalea Reef. - Information has been received from the Political Resident at Aden of the.existence of a sunken rock on which the steamship Azalea was wrecked, off the east side of Perim island, and stated to be at a distance of 387 yards from the shore. This danger has 11 feet water on its shoalest part and

XXIV. ADDENDA.

from it Perim Island lighthouse bears N.W. 3 N., the north-east point of the island S.W. by W. + W., and Bab-el-mandeb peak N.E.

It is reported that the tides are not to be relied on in this neighbourhood, and that the currents are variable and strong.

Ras-Gharib. - On the lst of December, 1871, a fiwed white light, visible 20 miles, was established on the point at Ras-Gharib, in lat. 28° 21' N., long. 33° 6' EK.

It is shown from an iron lighthouse, consisting of a centre column supported by three stays, painted red - the centre of the lamp being 165 feet above the sea. Pages 384 - 3887.

ADEW. - A lighthouse of dark blue stone and 69 feet high, has been erected on Ras Marshigh the eastern extremity of the peninsula known as cape Aden. It shows a fixed light at 244 feet above the sea, visible 20 miles. Its geographical position is lat. 12° 45' 28" N., long. 45° 4' E. It is of seivice chiefly to vessels approaching Aden from eastward; those westward of the port, can see it only when it is open southward of Ras Tye. Page 388.

KARACHI. - The coast of Sindh southward of lat. 24° N., should be very cautiously approached, there being in places a depth of 20 fathoms within 2 miles of, and 10 fathoms close-to, the outer edge of the banks which ue to the south-westward from the Kukiwari mouth of the Indus.

It is equally necessary to be careful not to get too close in with the land when northward of lat. 24° N., as it should not be approached into a less depth than 14 fathoms, when the vessel will be only 7 to 9 miles from the Hajamri and Kediwari banks of the Indus. These banks are very dangerous, there being in some places a depth of 10 fathoms close to their extreme edge.

Vessels approaching Karachi from southward should make a frequent use of the lead especially when in the vicinity of the banks just mentioned. It should also be remembered that the land behind them is low, and scarcely visible in clear weather from their outer edge, - in addition, the set of the tides and currents is very uncertain.

Ras Muari (cape Monze), distant 18 miles W. 3 N. from the western entrance to Karachi, is high and bold of approach. Ships, during the south-west mon- soon season, should make this headland, running to the eastward for Manora point, and keeping the latter on any bearing to the northward of East.

Light. - Manora point, on the west side of Karachi harbour, is 100 feet high, and has upon it a lighthouse and signal station. The light, fiwed, is 119 feet above the sea, and visible 17 miles; but in the hazy weather prevalent during the south-west monsoon, is frequently not seen at a greater distance than 7 miles, - its geographical position is lat 24° 47' 21" N., long. 66° 58' 15" E.

Manora point can be approached to within half a mile on any bearing from North to East, in about 5 fathoms water; but the port should, if possible, be made during day. From June to September vessels can approach within 1 or 2 miles of the lighthouse, keeping it from N.E. to North, and should then heave- to until boarded by a pilot or directed by signal. Entrance to the harbour should not be attempted without such assistance. From September 15th until the end of March ships may anchor with the lighthouse bearing N. by E. to N.N.E. distant one mile, in 7 fathoms water. During the months of April and May

ADDENDA. XXvV.

they should anchor in 8 fathoms, with the lighthouse bearing N.N.F. to N.E., distant 13 miles. i

The following instructions for vessels bound to the port were issued by Lieut. Geo. C. Parker, I.N., Acting Master Attendant, August 28rd, 1873 ; -

Tides. - High water full and change 10h. 30m. Average rise and fall - spring tides 9ft. 6in. ; - neap tides 8 to 4 feet. The average depth of water on the bar at high water springs is 28 feet; at neap tides 25 to 26 feet.

Draught of Vessels Entering or Leaving Port. - Vessels with a draught not exceeding 21 feet can now enter and leave port without any difficulty or delay during all seasons of the year. During the fair season, from October to 15th May, vessels of the largest class with a draught not exceeding 24 feet, can now enter and leave the harbour. Fixed moorings will be placed for such vessels.

Time of Tide for entering Port. - Sailing vessels should enter port on the ebb tide. Steamers can enter either on floud or ebb, and stand at once into port. Masters of ships should not, under any circumstances, attempt to enter the harbour without a pilot.

Harbour Improvements. - 'l'he harbour works are nearly completed, and have proved most successful, both as regards deepening the entrance channel and enlarging interior accommodation for shipping. Among the extensive works executed, a breakwater has been built, running out from Manora point in a S. by E. direction to a distance of 1500 feet into 6 fathoms of water; this affords com- plete shelter to the channel over the bar during the S.W. monsoon.

Also, a channel has been opened through the bar with a depth of 19 feet at low water spring tides, 300 feet in breadth (to be widened to 500 feet); the channel is marked with buoys, and these, on entering, should be kept on the port side, about 100 feet.

Note. - Every facility will be afforded (during the fair season only), for mail steamers to enter port during the night. A 'red light' will be placed at the end of the breakwater, and a light will be shown on the west side of the channel.

A mail steamer arriving off the port at night, and requiring a pilot, should fire 'two guns.' fi

GULF OF CAMBAY. - Light rivers discharge into the gulf of Cambay or Khambat; the Nerbudda or Narmada, Sabarmati, Mahi, Dhadar, Kim, Taptee or Tapti or Tapi, Bhaunagar or Ghadechi, and the Shetrunji.

The fall of rain in this part of the East Indies being very considerable (36 inches in the year), a great quantity of mud is carried by these rivers into the gulf of Cambay, discolouring the water, especially during the monsoon. After the latter, the water beyond the inflnence of the tide clears in some measure ; but on the " Bombay Bank of Soundings,' 100 miles below the head of the gulf of Cambay, it is always, more or less, muddy and discoloured. In the rivers, however, it cannot, on account of the immense amount of water flowing rapidly down, deposit ; they nearly all deepen, but some of them change only their chan- nels. The Nerbudda, for instance, the mouth of which lies against the flood stream, increases in depth, while the Tapi, on the other side of the gulf, frequently changes its channels. The mouth of the latter lies directly beyond a low promon- tory, called Vaux's Tomb, and situated in lat. 21° 5' 35" N., long. 72° 87' 30" E.

The Nerbudda is very easy to navigate ; the flood tide setting directly into it, and the rise of the spring tide at the mouth being from 25 to 30 fect; at the mouth of the Tapi the latter is only 19 feet.

XXV1. ADDENDA.

The width of the Nerbudda is, at the mouth, about 134 miles, and about 16 miles up the stream, above Mehegam (Mehegaum), it is 14 miles. Within this distance many places are dry, except in uncommonly high tides, occurring once or twice in the year, and others are just covered by the water. Between them are two channels, the southern of which, leading to Hansut, becomes dry at low water; the northern channel, which flows past Ambheta (Umbheta), is always navigable.

There is no bar off the northern channel, although older charts show two banks with a channel 1} miles in width between them; the tongue of sand, extending from the northern coast southward to a distance of from 4 to 43 miles, may be the cause of the many reports of the existence of a bar.

The part of the channel between the mouth and Ambheta has recently changed 14 miles to the westward; it does not any longer trend from Ambheta down- ward in a south-western direction, but goes in a western direction to nearly opposite the village Lohara, and thenee directly south.

The above-mentioned tongue of sand has been carried away outside to a con- siderable extent, so much so that, half a mile above its point, it is now only 13 miles wide, instead of 43 miles, as shown on the charts. But it has grown in length, the point being at present half a mile farther south than shown on the charts. It is probable that in the course of time the river will break through the tongue directly west into the gulf, where there is very deep water, the depths being between 7? to 153 fathoms at a short distance from the land.

Between the outer mouth and Ambheta is a narrow and ve'y shoal channel, about a mile above the point of the sand.

The width of the main channel is, at the mouth, more than a mile, and the depth outside, near the buoy (lat. 21° 34' 30" N., long. 72° 380' 20" E.), is now 63 fathoms ; formerly, it was only 3 fathoms.

N. 56° E., distant about 14 miles from the outer buoy, lies the inner buoy, the water near it being from 3;°, to 5,8, fathoms; formerly, it was only 1°, fathoms. The depth remains about the same up to Ambheta. This shows that the channel of the Nerbudda improves steadily by its own action.

Directions. - Besides the main channel passing Bharukh, there is also a channel along the southern shore of the river, opposite Bharukh, but only for small craft at high tide; large vessels cannot cross the bar there.

Beyond Bharukh (Baroche) the railroad crosses the river, whence the deepest channel remains near the northern shore. Below Bharukh the channel crosses over to the southern shore, running then some distance up, to a creek or cut open to the southward, opposite which the water shallows, forming a bar, over which at present large shipscannot pass. The channel recrosses to the northern shore, remaining there up to about 44 miles below Bharukh, in the vicinity of Dasar village, where it divides into two branches, the northern of which is much narrowed by an island, while the southern is comparatively dry. The northern branch runs along the high northern shore for about 5 miles, making a curve toward the south, with a depth of 18 to 25 feet at spring low tide close to the shore (50 feet distant) and across the greater width of the river. Many ships may be moored here or may lie at anchor, those of 15 to 16 feet draught remain- ing afloat at all stages of the tide. Lhe depth remains the same to a point

ADDENDA. XXVIl.

opposite the village Samni, on the northern shore of the river, whence the chan- nel again crosses over to the southern shore toward a cut or creek, running past Hansut Bandar, which is the southern channel at the mouth, mentioned previously as becoming dry at low water.

From opposite Samni, where a narrow shoal extends along the northern shore, the channel leads to Mehegam, where, beside it, another creek or cut exists, ealled Bhuki or Badri. The water in the channel proper is here comparatively shallow, but never less than 6 feet at low tide; a buoy is moored here. 'The rise of neap flood is 64 feet and of spring flood 17? feet ; the average water is about 18 feet in neap tide and 24 feet in spring tide, sufficient for all vessels of 15 feet draught, except in the lowest neap tides. From Mehegam the channel runs along the northern shore, past Kaladra, to near Vingni, where a high and sharply defined bank exists with 8} feet over it at lowest high water neaps, and 19} feet in spring flood tides; the lowest neap tides, however, occur but rarely and last only for three days.

From Vingni the chanuel crosses again to the southern shore, and widens to 134 miles; it passes Karsalia (Bet) island, along the high shores of which the water is deep close to; there is, however, some shallow water near the first point of the island, where a buoy is moored in 8 feet at low tide, but the high rise of tide prevents any disturbance of navigation.

The channel runs along the southern shore to opposite Suva on the northern shore, whence it again bends north, touching the shore about 2 miles from Ambheta. There also exists a small shoal, which, however, does not impede navigation. The flood rises here extraordinarily high, and there is in this part of the river everywhere from 24 to 27 feet of water at spring low tide, so that the largest vessels remain afloat at any stage of the tide.

The prevailing belief is that the river changes every year considerably ; but on comparison of its present state with the Admiralty chart published in 1845 (showing the river as far as Mehegam), it will be found that these changes are for the better. 'The only part which has changed greatly is that near the mouth.

Smaller changes occur, doubtless, every year during the monsoon, especially near and at Bharukh; everywhere else the powerful flood soon removes any obstacle.

The tidal observations show the flood to last on the average 8 hours, and the ebb 9 hours, varying probably in some parts, but only a little. The quantity of water in the upper part of the river at low water is greater in spring tides than in neap tides, as then each succeeding flood ascends before the preceding has descended. Very close observations confirm that in spring tides the rise is greater than the fall, and in neap tides the reverse ; for instance -

Spring tide- - Rise 94 feet, fall 8} feet; rise 52 feet, fall 44 feet ; rise 93 feet, fall 83 feet.

Neap tide. - Rise 2} feet, fall 2% feet; rise 3% feet, fall 5 feet; rise 2} feet, fall 34 feet.

The flood differs also in day and night time; the higher flood is during the night. 'The rise of tide in the mouth of the Nerbudda is 25 to 294 feet.

The latter height was observed November 20th 1870, at the new moon. The water then rose in the three hours ef the flood tide 9% feet per hour, or 0°16 feet

XXVlli. ADDENDA.

per minute. When such a flood enters the gulf the stream must naturally be very strong, and ships may readily drift; the roaring of the water can then be heard in the dead of night at a great distance. There is never a flood-wave in the Nerbudda as in other rivers, owing to its width at the mouth, which is a flat basin, over which a great quantity of water distributes before entering the nar- rower part of the river above Mehegam.

During the monsoon the motion of the water in the mouth of the Nerbudda is very considerable, especially at the beginning and when the flood meets the water coming down. The sea then rises very high, similar to the sea off cape Guardafui, and at the Agulhas bank south of the Cape of Good Hope, during the monsoon. Only good stout vessels can then enter the Nerbudda, and even such had better remain outside. But as soon as they have entered and reached the inner buoy, 14 to 2 miles up the river, they are well enough protected except in severe gales, and even in such they are secure at Ambheta.

The navigation of the Nerbudda is, for ordinary ships, easy at all times ; steamers commanded by experienced masters can reach the deep water beyond Samni, and 4 or 5 miles from Bharukh, in one flood tide, and under all cireum- stances in two. For sailing vessels two or three flood tides are required for reaching that place.

In navigating the river the tides must always be taken into account more or less, especially for long vessels with little beam. If not obeying the helm quickly below Bharukh or near Mehegam, they will ground or run on the banks, not for the want of water, but on account of the relative position of the banks. Sailing vessels are apt to ground in beating, from the same cause.

Well-built vessels, however, will not be damaged essentially by grounding, the bed of the river being very smooth, and the bottom principally fine sand, or here and there soft mud.

The directions for entering the river are: from the outer buoy the light tower of Perim bears N. 85° W., distant 10 miles; the chanuel trends N. 56° E. for 14 miles to the inner buoy in 3,°, fathoms spring low water; from the inner buoy the channel trends north 34 miles to the beacon, beyond which it is well defined by the banks. An experienced navigator will know where he may lay secure, waiting for the tide, in case he cannot sail up with one flood.

The first of such places is Ambheta, the second near Vingni, and the last beyond Samni. Each of them has good anchorages in deep water, at all stages of the tide, for vessels up to 14? and 16 feet draught.

The navigable part of the river could be improved greatly by closing the creeks or cuts on the southern shore, especially that below Bharukh and that leading past Hansut.

The navigation of the upper part of the gulf of Cambay to Gogha, Bhaunagar, and Dholera, has no difficulties, as the water is deep, with good anchorages ; the farther up the gulf the greater is the influence of the tide. Ships at anchor off Mahi are exposed to drifting, and may readily get high and dry, especially when the prevailing S.W. wind exercises its full influence on the tide and increases the currents. At Gogha this danger is lessened through the protection of Perim island; but even here the sea rises, during the height of the monsoon, to a formidable height; the storm-waves are dangerous at all times. Notwithstanding these drawbacks, a mole might readily be built opposite Gogha if the commerce

ADDENDA. XXEX-

was great enough to justify the expense; the construction would be less hazar- dous than at Madras, on the Coromandel coast.

Directions in Brief - A large red buoy, surmounted by a basket, lies at the entrance in lat. 21° 34' 30" N., long. 72° 30' 20" E.,in 6? fathoms water at spring low tide, the light tower of Peram bearing N. 85° W.,distant 10 miles. The buoy is 2 mile distant from the banks, and is the leading mark for the channel.

A second large red buoy, marking the bend of the channel, lies in the middle of it, in 3,°, fathoms water, spring low tide, the outer buoy bearing from it S. 56° W. distant 13 miles.

A beacon stands on the northern shore at the high-water line, bearing North (true) from the inner buoy, distant 38} miles. From the outer buoy, steer E. until the inner buoy bears N.IK. by N., then steer for the inner buoy and pass it to the N.E. From the inner buoy steer N. for the- beacon, and then along the northern shore toward a group of trees surrounding a temple close to Ambheta, where deep water will be found close to the north shore.

The least water in the entrance at spring low tide (15 feet) is between the two buoys. Between the inner buoy and the southern shore the depth 5,8, fathoms, with room enough for a large vessel to swing.

Perim Light. - The fixed light on Perim island is from a white stone building 78 feet high ; it is 128 feet above the sea, and visible 17 miles. Its geographical position is lat. 21° 35' 54" N., long. 72° 23' 38" E.

Tapti Light - The /fived light at Tapti ison a column 91 feet high, and painted in red and white bands, erected on the north side of the river, in lat. 21° 5' N., long. 72° 88' E. It is at 100 feet above the sea, and visible from an offing of about 15 miles. Page 407.

BomBay. - A lighthouse consisting of an octagonal tower on the centre of a flat roof house has been erected on Kennery (Kundari) island, south of Bombay harbour. It shows a fiwed light at 161 feet above the sea, visible from all parts of the sea horizon at the distance of 20 miles. Its geographical position is lat. 18° 42' 20" N., long. 72° 48' 50" E.

The Outer lightvessel now shows a red light, revolving in 20 seconds.

The fairway buoy has been removed. Page 410.

Signal Station. - The following is a revised code of urgent signals for use at Kennery (Kundari) island, to be repeated by the Pilot schooners, the Outer light- vessel, and at the Kolaba Signal Station : -

No. of Signal. Gun Signals. Signification. Yt, Two guns in quick succession. A vessel is running into danger. 2. One gun, followed after an A vessel is ashore.

interval of a minute by two guns in quick succession ;

thus O - OO 3. Two guns in quick succession, Vessel for which No. 1 signal was followed by an interval of made is now out of danger. a minute by one gun; thus OO - O

A, Two guns, at an interval of |= Kennery Lifeboat is disabled. one minute.

XxX. ADDENDA.

5. Three guns, at an interval of Medical aid is urgently required one minute. at Kennery.

6. Four guns, at an interval of Communication with Bombay is one minute. urgently required.

The above signals are to be repeated every five minutes until replied to by the Outer lightship and at the Kolaba signal station. The pilot schooners are to repeat the signals (made at Kennery either by guns, flags, or distant signals) by showing the corresponding signal in the Commercial Oode under the red ensign, Union down, at the mast-head, and they are to close with and communicate the same to the Outer lightvessel and to the Kolaba signal station. For instance - If No. 1 or No. 4 signal is made at Kennery, the pilot schooners will hoist V.W.G. or V.W.K. under the red ensign, Union down. The Outer lightship will repeat all signals until replied to at the Kolaba signal station. Pages 408 - 410.

Trade between Bombay and Europe, via the Suez Canal. - During the South-west Monsoon. - The Salvage Association has issued the following mem. on this subject, furnished by Commander J. A. Heathcote, late I.N.: -

The South-west monsoon sets in at Bombay early in June; to the southward of Bombay it begins earlier, the average date of its commencement at Mangalore being the 20th May. Ships leaving Bombay in May for the Suez canal will certainly fall in with the monsoon in crossing the Arabian sea.

In June, July, and August steamers leaving Bombay harbour, after making an offing, generally govern their course by the winds which may blow from W.N.W. or from W.S.W., and from that to S.W. They run to the southward, steering as near to the wind as possible, to allow their trysails to draw, until they find that, as they get to the latitude of about 6° N., or to the southward of that, the mon- soon is there sufficiently moderate to allow them to make their westing under steam alone.

About the meridian of 54° or 55° E. they will begin to haul up to the N.W., and when reaching about the lat. of 9° to10°N., it is well to keep not too far from the African shore; for, by keeping well in with it, a strong favourable cur- rent running to the northward is experienced, whereas, about 109 miles further out, to the southward of Socotra, a very strong current to the E. and E.S.E. is found, and this current is of such force that if a vessel once gets into it she may lose her passage altogether, and be obliged to bear up before the wind for the port of Bombay again.

The passage against the South-west monsoon is, no doubt, one which is likely to strain any but a very well-conditioned ship. Steamers with only very small steam power in proportion to their size may find difficulty, or at least be detained, in making this passage. Sailing ships making this passage have to go very - much further south than steamers, sometimes even finto the South-east trades, in order to make their westing; they frequently pass to the southward of the Chagos archipelago, and then cross the Line again to the northward, about the longi- tude of Ras Hafan.

The passage from the Red sea to Bombay, in the South-west monsoon, is one which any well-conditioned ship can make without difficulty; the only anxious part of the voyage is when approaching Bombay harbour. In doing this, the great point is not to get to the northward of the harbour, and to pay particular atten- tion to the lead. A powerful light now established on Kennery island causes the

ADDENDA. XXX1.

making of Bombay harbour by ships approaching it in the South-west monsoon to be much less hazardous than before. Pages 407 - 412.

RATNA GHIRI, at about 115 miles southward from Bombay. A fixed red light is shown here from the south-west bastion of an old fort; it is 300 feet above the sea and said to be visible from the distance of 18 miles. Its geographical position is lat. 16° 59' 30" N., long. 73° 15' 47" KE.

Anchorages. - At Ratna Ghiri there are three anchoring grounds : - The outer anchorage for sailing vessels;*the outer anchorage for steamers; and the inner anchorage for steamers during the fair season only.

Vessels anchoring at the outer roadstead should do so in 8 fathoms, at a little more than a mile from the lighthouse, with the lighthouse bearing N. 59° 4' E. or N.E. by E. } E.; Adawlut building, (a very large house on the hill bordering the creek to the North) N. 81° 33' EK. or E. ¢ N.; and the white tomb, (near the - beach southward of the creek), S. 75° 56' E. or E. by 8.358.

Steamers making the port at the beginning or close of the South-west monsoon should anchor in 6} fathoms with the lighthouse bearing North and the Adawlut building E.N.E.

The inner anchorage is only available for steamers during the fair season. Vessels should anchor in not less than 4 fathoms with the lighthouse bearing N.W.3N. and the Adawlut building E. by N. 4 N. ; - that position will place them at about 1200 yards from the landing place and 700 yards from the edge of a ridge of rocks running out from the beach in front of the custom-house.

The port of Ratna Ghiri does not afford the least shelter to vessels during the South-west monsoon, but a .vessel in distress would, in a measure, be sheltered by anchoring in 5 fathoms after rounding the north point of Meria Donghur, a hill 8 miles northward from the lighthouse. .

The bay between Meria Donghur and the lighthouse hill does not afford any shelter, but on the contrary, is open to the full force of the monsoon. Page 418.

VINGORLA. - Two fixed white lights are exhibited from the headland over- looking the Vingorla roadstead, visible seaward a distance of 9 miles. The lights are placed 20 feet apart and at an elevation of 250 feet above the sea. These lights will not be shown during the S.W. monsoon, that is, from 15th June to 31st August, inclusive. Page 413.

VINGORLA ROCKS. - A fixed light is shown from a lighthouse erected on the outermost of the Vingorla rocks or Burnt islands ; it is elevated 110 feet above the sea, visible 15 miles.

From the lighthouse, Vingorla point bears I. by 8. 94 miles, and Malwan, North 94 miles. Position, lat. 15° 53' 20" N., long. 73° 26'40"" EK. Page 413.

caxicutT. - A black buoy has been moored off this port in 4 fathoms, to mark the inner edge of the best anchorage ; it lies with the lighthouse bearing E. 3 S., and Conolly hill N.E. by N. To avoid dangers when passing to or from south- ward and in the vicinity of Cooty reef, great care should be taken not to bring the buoy westward of North, as there are several shoal patches of rocky ground close inside of that bearing (1869). Page 416.

cocuin. - The new lighthouse is of white stone and 89 feet high ; it showsa

XXXI. ADDENDA.

fixed light at 95 feet above the sea, visible 14 miles, Its geographical position is lat. 9° 57' 50" N., long. 76° 14' 40" &. The light referred to in the text has been discontinued. The best anchorage in the roadstead is in 53 to 6} fathoms, soft ground, at from 2 to 24 miles from the shore, in the direction of W. 3 S. to W. by N from the lighthouse. (1868).

Limits of the Port. - The limits of the Port are as follows: Zo the North - The boundary pillar, 1 mile north of the Northern point of the entrance to the harbour or back water.

To the South - The boundary pillar, 3 miles south of the Southern point of the entrance to the back water.

The sea shores between them to within 50 yards of high water mark, spring tides.

To the Hast. - The harbour and back water with all creeks and channels leading thereto, that may be within the Indian Government territories, and so much of the shores thereof, whether of the main land, or the islands, as are within 50 yards of high water mark, spring tides.

To the West. - The space enclosed by two lines, running due West from the boundary pillars, to 9 fathoms water.

Anchorage. - The best anchorage in the roads is with the following bearings: flag-staff EK. } N. to E.N.E. in 53 to 64 fathoms, soft ground, about 2 to 24 miles off shore. Page 416.

WARRAKEL. - A first class buoy, painted red, is moored in 18 feet water, soft bottom, with the Narrakel flagstaff bearing E. by S. 4S.

The best anchorage in the South-west monsoon is with the buoy bearing East to E.S.E., in from 33 to 44 fathoms. Vessels of small draft, from 12 to 15 feet, can anchor close to the buoy.

The buoy will remain in position throughout the South-west monsoon, and is seen from a distance of about 3 miles.

The Master Attendant's office, which has been recently erected a little to the northward of the flagstaff, will be clearly seen from the offing as a white object, and form a good guide to ships running in for the roads. (May 7th, 1867). Pages 417 - 419.

GREAT BASSAS ROCKS. - See List of Lights page ix.

WMOELETIVOE (N.E, coast of Ceylon): - There is reason to believe that the shoals off Moeletivoe, have extended further seaward. Mariners are accordingly cautioned not to approach that portion of the coast into less than 20 fathoms water until they are certain the shoal ground is cleared, as on some of the ridges there is not more than 12 feet water. Page 440.

POINT CALIMERE. - The land at this point has suffered so much from the sea, that the beacon upon it is now surrounded by water. At about a mile inshore is a flagstaff. The two pagodas in lat. 10° 224' N. bear West, when in line. Page 448.

NEGAPATAM SHOAL is a small patch of about a mile in extent, and with only 3 fathoms upon it; it is in lat. 10° 86' N., long. 79° 55' E., and consequently 3% miles from the beach. From it a narrow 4-fathom tongue extends 44 miles

ADDENDA. XXXlil;

due North, in a direction parallel to the coast; and also extends southward from it until at last it joins the flats off point Calimere. Ata mile eastward from it the depth is 7 fathoms, and immediately westward of it 5 fathoms. As the channel between this shoal and the shore is shallow for a distance of 2 miles from the land, vessels approaching Negapatam from southward should keep eastward of it, in a depth of not less than 8 fathoms. Page 448.

JEYTAPUR (West coast of India): - A fixed white light has recently been established on Keeva hill at Jeytapur; itis elevated 75 feet above the sea, visible about 9 miles. Position, lat. 16° 86' 10" N., long. 73° 18' 30" E. From June 11th to September 9th, inclusive, during the South-west monsoon, the light is extinguished. Page 413.

COLEROON SHOAL, in lat. 11° 27' N., consists of a sandy flat at the mouth of the Coleroon river. It projects from the shore about 1} miles, and at a mile eastward from it is a depth of 7 to 9 fathoms. Page 448.

TRIPALOOR REEF, in lat. 12° 37' N., extends one mile from the land, and is immediately succeeded by a depth of 5 and 6 fathoms, deepening to 11 and 12 fathoms at 24 miles from the beach. This reef runs off the coast at the seven Moolivaram pagodas. Page 449.

The bank in lat. 12° 26' N., 10 miles from the shore, reported to have been sounded upon by Captain Barclay, does not exist. The depth in that latitude and at that distance from the shore is 23 to 25 fathoms. Page 449.

CORINGA. - iloyd's agent, dated Cocanada, Feb. 3rd, says: - ''The port of Coringa has for a long time been abandoned as an entering and clearing port for ships under command of Europeans, and it is entirely confined to native vessels of small draught of water. All ships come to Cocanada and must clear from Cocanada; vessels do not communicate with Coringa officially." Page 456.

GOPAULPORE. - A light is now exhibited at Gopaulpore, Bay of Bengal. It is a fixed white light, exhibited from a flagstaff, and elevated 89 feet above the sea ; visible 8 miles.

The position of the flagstaff is lat. 19° 13' N., long. 84° 52' E.

' Directions. - Vessels making the roadstead should bring the light to bear N.W. 4 W., and anchor in.from 8 to 9 fathoms water. Page 463.

MORELLGUNGE (Huringotta River). - This-port has been declared by the government surveyor to be safe of access and egress during the North-east mon- soon, for vessels drawing 17 feet water. The entrance has been buoyed, and the port is very favourably situated for exports of rice from Bengal.

With reference to the South-west monsoon, though the port may be con- sidered safe for vessels entering during that season, because as the wind would be fair for entering, the time for running in may be chosen so as to carry high water over the shoal part of the entrance, yet the coming out during the South- west monsoon is reported (also by the surveyors of the government of India) to be not safe for vessels under sail, drawing above 12 or 13 feet, because the ebb tide has to be taken advantage of to enable the vessel to beat out, the wind being contrary, and the extent of shoal water is so great, that a portion of it must be crossed at low water. At low water spring tides, on the lower part of the shoals there is only 16 feet of water, therefore, with the swell and sea of the South-west monsoon, it is plain that vessels under sail cannot come out from the Huringotta

c

XXXIV. ADDENDA.

river drawing above 13 feet at the most. Therefore, for vessels drawing above 13 feet of water, steam is absolutely necessary in coming out during the South- west monsoon, and even then it would not be safe that a vessel, either a steamer, or in tow, should draw more than 16 feet during the height of the season.

About the entrance of the Huringotta river the South-west monsoon may be taken to last from April to September.

Directions. - The following directions for entering the Huringotta river from sea were published by the Government of Bengal in i869 : -

The channel leading from sea into the Huringotta has been buoyed as follows ; -

The outermost or fairway buoy is a first class spire buoy painted white, and laid in lat. 21° 26' N., long. 90° E.,in 6 fathoms low water spring tides. The lower Landfall flat buoy is a second class spire buoy painted black ; it hes in 32 - fathoms low water spring tides, 7 miles N.N.W. from the fairway buoy. The Argo flat buoy is of the same description, but painted red ; it hes in 2? fathoms, about 63 miles N.N.W. 4 W. from the eastern buoy. The upper flat buoy is of the same description, painted black, and lies in 23 fathoms, about 63 miles N.E. 3 N. from the Argo flat buoy. The lower spit buoy is a second class spire buoy painted biack ; it lies in 24 fathoms, about 6 miles N.W. by N. from the upper Landfall flat buoy. The upper spit buoy is a third class buoy painted red, laid on the south end of the spit above Tiger point ; it bears from Tiger point N. 4 W., distant about 7 miles.

A beacon with a basket on it is placed on Tiger point to mark the point, and a similar one on Deer Point bush.

Vessel bound for the Huringotta river in the North-east monsoon should first make the fairway buoy, and then stand over on the starboard tack till the lower Land- fall flat buoy is sighted. Should, however, the wind be well to the northward, and the buoy is not sighted, they should take care to tack to the eastward in time, as there is usually a westerly set of from 1} to 23 knots per hour during this period of the year. After sighting the lower Landfall buoy vessels should tack as soon as they can fetch it, and when clese to it they will be fairly in the channel ; they should then work to windward during the flood tide and anchor at high water.

Vessels drawing less than 14 feet can anchor in any part of the channel during the North-east monsoon, but if drawing more than that they must anchor below the Argo flat buoy, unless they can make certain of passing the spit buoy before the tide is done.

In working up, the lead will be found a safe guide, as the soundings in the channel are all soft mud, but the following bearings of the buoys should be attended to ; -

In standing to the westward - The Argo flat buoy must not be brought to bear to the eastward of N. by E.4 14., or to the southward of S. 4 W., when to the northward of it. And the spit buoy must not be brought to bear to the eastward of North.

In standing to the eastward - The lower Landfall flat buoy must not be brought to bear to the westward of S. by W.4 W., and the upper Landfall flat buoy must not be brought to bear to the westward of N. by W., or to the westward of S. 4 W. when above it.

Vessels should pass close to the spit buoy, when they will be in the channel,

ADDENDA. > & 4

and must not stand over to the westward further than to bring Tiger Point beacon to bear N. by W.; when this bearing is on, they should tack, making short tacks to the eastward all the way up the channel. Having passed Tiger point, a vessel may stand close in shore on the starboard tack, making short boards over to the eastward till abreast the upper spit buoy. After passing it, the tacking mark tothe westward will be the buoy bearing South, when short boards must be made to the eastward, till Deer Point bush is reached. Being to the northward of that, the water is deep close to on the eastern shore, and short boards must be made to the westward till clear of the upper spit shoal. The vessel will then be fairly in the river and clear of all dangers, and careful attention to the chart by Lieut. Sweeney will enable her to proceed in safety to Morrellgunge.

It is to be understood that these directions have been framed from the latest survey in 1861 by Lieut. Sweeney, but as he found very little alteration since 1840, the date of Captain Lloyd's survey, it may fairly be assumed there has been no material alteration in the channels up to date.

It is high water at the fairway buoy, full and change, at 10h.

The port will be opened during the North-east monsoon only, and by attending to the above directions, and by a careful observation of the chart and attention to the sounding, no difficulty can be experienced by a commander of a vessel in making or leaving the port.

Beyond the above aids, commanders visiting the port musf rely upon their own skill. Variation 2° EK. Page 465.

PORT CANNING. - It has been decided to close Port Canning, and to with- draw all harbour establishments from the Mutlah except the outer lightship. (1871). Page 469.

CHITTAGONG RIVER, - T wo /ived lights are now shown on Norman point, a short distance southward of the entrance to this river, at the respective heights of 38 and 30 feet above the sea, visible about 8 miles. During day, the point may be recognised by a barrel-shaped beacon on a tripod 65 feet high.

Vessels making the port should sight the lights on the bearing of about N.E. They should approach them on the bearing of N.E. to E.N.E. and when distant about 3 miles from them, should anchor or wait for a pilot. Page 472.

AKyAB. - The lighthouse on Savage island has been altered from a fixed to a fixed and flashing light, showing a flash every minute. The light is elevated 99 feet above high water; visible 13 miles. (1871).

The light which was temporarily exhibited from the table-land of Borongo island is extinguished and the structure is destroyed.

A flagstaff carrying a ball at the mast-head stands on Oyster island. It is 82

feet above the sea-level and bears from the lighthouse on Savage island N. 69° W., distant 21 miles. Page 473.

RANGOON RIVER,- - The following lights are now (1873) exhibited at the entrance to Rangoon river : -

The lighiship which formerly marked the entrance to the Rangoon river has been removed.

A coast light due of one anna a ton is levied on all ves els of 5° tons burden and upwards, if the voyage be from Rangoon or Maulmain to Bassein, or from Bassein to Rangoon or Maulmain.

e 2

XXXVI. ADDENDA. >

Krishna Shoal Lighthouse. - A lighthouse on screw-piles in 3 fathoms at low water, near the south-western end of Krishna shoal, shows a fiwed light at an elevation of 60 feet above high water, visible 14 miles. Rise and fall of tide 12 feet. H.W. at F. and C. XII hours. The light is cut off at W.S.W. tothe westward, and at N.N.E. to the eastward, the centre of the light being South- east. Position, lat. 15° 36' 30" N., long. 95° 35' EH.

It is provided with a fog-bell which, in foggy weather, is sounded at intervals of 30 seconds.

Directions - In making the light (the object of which is to enable vessels to round Baragou point so as to avoid the dangers of the Baragou flat and Kiishna shoal) from westward, a vessel should keep in not less than 7 fathoms water to the southward, steering eastward until the light bears N.W. and distant 5 to 10 miles, then steering according to the strength and set of the tide, between N.K. by N., and N.E. 40 miles, to make China Buckeer lighthouse off the mouth of Rangoon river.

Vessels from northward going south must not get into less than 6 fathoms water when standing to the westward, or bring the light to bear to the southward of S.W. by W. + W.

No vessel should approach within 5 miles of the lighthouse.

A vessel bound westward may steer in that direction after she has brought the light to bear North, distant 5 to 10 miles. taking care to keep in not less than 7 fathoms. water.

China Buckeer Lighthouse. - This lighthouse is situated on the high land of China Buckeer, which is generally first made by ships bound to Rangoon, and is about 3 miles north-east of the mouth of China Buckeer river. It is built on screw-piles, and the lower part being against a back ground of dark trees is painted white. It is close to high water mark, but the sands at low water stretch 6 miles eastward from it; ships must therefore keep well to seaward. It shows a revolving light attaining its greatest brilliancy once a minute. The light is elevated 74 feet above the sea, and visible about 15 miles. Position, lat. 16° 19' 30"'N., long. 96° 12' E.

Eastern Grove Lighthouse. - This lighthouse is also on screw-piles, in lat. 16° 29' N., long. 96° 26' 30" E. It shows a fixed light over an are of 60° (South to 8. 60° W.). An arc (10°) of greater brilliancy is shown from S. 25° W. to 8.-35° W. (over the position formerly occupied by the lightvessel). The light is elevated 93 feet above the sea, visible 12 to 16 miles. It is not intended to bea leading light into the river, but to prevent vessels, making the land or China Buckeer light, from running too far to the westward.

Directions. - To make the mouth of Rangoon river steer so as to make China Buckeer light bearing between N. by E. and W. by N. To avoid the Eastern sands, a vessel should not go so far north as to bring the light to bear to the southward of W.4 N.; and to avoid the Western sands, the Eastern Grove light- house must not be brought to bear to the eastward of N.N.E.4E. With China Buckeer light bearing W.4N. and the Eastern Grove light bearing between N.N.E. + E. and North, vessels will be on the Rangoon pilot station, in the neighbourhood in which pilot vessels are constantly cruising, and should anchor

ntil daylight, or until a pilot is obtained. Pages 481 - 483.

MAULMAIN. - The light on Amherst point is discontinued. Page 485.

ADDENDA. XXXVI.

DOUBLE ISLAND. - The lighthouse on this island shows a fired light, visible at the distance of 19 miles. Its approximate geographical position is lat. 15° 52' 30" N., long. 97° 36' 80" E., and from it Amherst point bears N. 3 W.; the Patch buoy N. by W. 4 W.; and the west point of Kalegouk island S. by E. The arc illuminated is 1643° (from N.N.W. westward to 8. ? E.); the bearing of N.N.W. passes 14 miles westward of the Patch buoy, off Amherst ; that of S. $ E. i; miles westward of Kalegouk island.

A strip of light is shown from the Patch buoy eastward as far as Amherst point.

Vessels making the light should endeavourto keep it between the bearings of S.E. and N.E., paying particular attention to the tides, as at springs they run about 5 knots an honr, parallel with the coast. If the land be too closely approached the light will be lost to view, but so long as the light is in sight, they will be in no danger until they are 10 miles northward of it, when they will be in the neighbourhood of the Goodwin sands, where the tides are very strong. The anchoring ground in the vicinity of Double island is good, but, on account of the strength of the tides, vessels should avoid as much as possible the risk of anchoring in such deep water. Page 486.

PAK-CHAN RIVER (Bay of Bengal). - The following directions for the Pak- Chan river have been furnished by Navigating Lieutenant James Harry of H,M.S. Spiteful, Commander Mostyn, R.N. This officer also reports that in several places in the channel where 7 fathoms are shown in the survey of 1847, rocks are visible at low water 3 and 4 feet high.

To enter the Pak-Chan river vessels should coast along Saddle island, which will be easily recognized by two saddles, one on the north part of the island the other on the south. the latter being the higher, taking care to avoid the shoal water which extends north-westward from the north end of Delisle island. When abreast Tree island, which is small, nearly awash, with one or two trees in the centre, steer to pass between Harry head (the northern point of Saddle island) and the Spiteful rock, rounding the head about 13 cables distant, hauling to the eastward for Stainer rock, which like Tree island is low, with trees about its centre ; this course will lead clear of the reef in mid-channel, 8S.S.W. of Mostyn island, over which the tide sets strong; when abeam of Stainer rock, bearing about S. by W. to $.S.W. haul to the north-east, passing Dyke island about a cable distant, and when to the northward of the north-east point of Victoria island, the vessel will be clear of the dangers in the river between that and Malewan creek. (1869). Page 489.

MERGUL ARCHIPELAGO. - The following information relating to the Mergui archipelago has been furnished by Navigating Lieutenant John Phillips and W.H. Hayward, of H.M.S. Forte and Dryud. 1871: -

Cabosa is the northernmost island of the outer group. and has a small islet on its north side. It is of moderate height and thickly covered with jungle.

About midway between it and Tanasserim island (the next large island to the southward) and nearly 5 miles east of the western Canister. a small steep high island densely covered with jungle, is a group of pinnacle rocks above water.

Freak Island is low with only a few scraggy trees on it, and surrounded by rocks. A line, joining this island with the western Canister, passes to the south- ward of the above-mentioned group of pinnacle rocks.

Brown Rock, lying about 18 miles E. by S. from Cabosa and from 8 to 9

XXXVI. ADDENDA.

miles $.S.W. of the small Canister, shows well above high water. No dangers are visible between it and Freak island.

Iron Island lies to the south-east of the small Canister; the depth of water along its eastern side, at a distance of about 2 miles off the shore, is from 14 to 18 fathoms.

Lord Loughborough Island, in lat. 10° 25' N., long. 97° 57' E., is about 7 miles long and 3 miles broad, high and steep-to. Three-quarters of a mile from the shore, on the north-east side, the soundings are from 17 to19 fathoms. Nearly abreast the eastern point and half a mile from the shore, is Hayward island, with rocks showing a short distance off; these rocks are steep-to, and there is good anchorage off this island in 17 fathoms, clay.

Between Loughborough and Richard islands there is good anchorage in from 8 to 15 fathoms, mud. Through the channel separating these islands, 3 fathoms will be found close to the shore, on either side.

To the eastward of Richard island are three other islands, O'Connor, Saul, and Skinner; the northern of which, O'Connor island, alone appears in the charts. They are of irregular form, about the same size, and are said to be dangerous to approach from sunken rocks between and about them. Vessels passing between these islands and Richard island, should keep the latter on board.

Bird's Nest Island is said to be much narrower than shown on the chart.

St. Andrew Sah Lr wets Sado Islands. - The three islands to the northward of C. island are in one upon a S. 3 W. bearing; they are a mile to the southward of the position assigned them in the chart. The island as shown between them and F'., on the chart, does not exist: but there is a dangerous rock, not marked, named Parson rock, dry at low water, from which North Cockburn island bears W.:5S., and the north point of C. island, S.W. by S. The east point of Bird's Nest island, bearing North, or a conspicuous round island covered with jungle, off the east side of C. island bearing South, clears Parson rock to the westward.

The Zides in the different channels of the Mergui archipelago run east and west, the flood setting to the eastward.

The Hydrographic Office publishes the following account of outlying dangers in the Mergui archipelago, not marked in the charts, on one of which H.M.S. Daphne grounded on the 5th July 1872 : -

The Oubliee Rocks, in the north-west part of the archipelago, one about 12 feet high, and the other awash, are nearly one mile apart, north-west and south- east. They lie nearly 23 miles to the northward of the north-west point of Elphinstone island, and 3 to 4 miles N.E. by I. of Saddle island, with 15 fathoms between them and Elphinstone island. The position given to these rocks is lat. 12° 30' N., long. 97° 59' E.

The reef shown on Admiralty chart No. 216 a, Mergui archipelago, as lying off mount Elphinstone, was not seen, and probably does not exist.

Warning Rock, awash at low water, lies between Court and Lord William Bentinck islands, about 4} miles E. by 8.2 8. from the south-east point of the former island. 'Lhere is 10 fathoms a mile to the northward, and no bottom at 13 fathoms half a mile to the eastward of the rock. The channel between Warn- ing rock and the reef *' above water,' 1! miles 8. by E. of the rock, appeared to be clear.

The position given to the Warning rock is lat. 11° 54' N., long. 98° 6' E.; but as the rock was only observed in passing, this position must be considered as approximate.

ADDENDA. XXXIX.

Daphne Rocks, on which H.M.S. Daphne grounded, are just covered at low water ordinary tides, and lie north and south, about 100 yards long by 50 broad, consisting of several large boulders with 12 feet on a bottom of sand and mud, between them at low water. They are nearly one mile distant from the mouth of a small creek on the eastern side of Lord William Bentinck island, with 9 and 10 fathoms between them and the land.

From the rocks the east point of West Passage island (off the north-east point of Lord William Bentinck island), was open about one-fifth its apparent length of the western peint of South Passage island. The south-east extreme of Lord William Bentinckisland bore S. ? E., and the centre of the small creek W. ?N.

The position given to the Daphne rock is lat, 11° 42'N., long. 98° 7' E. Variation 2° H, (1872). Page 489.

PORT OF PENANG. - The following Port Rules have been made by the Governor in Council for the Port of Penang : -

1. The Port of Penang is declared to be a Port subject to the provisions of this Ordinance. (Ordinance for the regulation of Ports and Harbours).

2. The limits of the Port of Penang are as follows : - From an obelisk built at Klarwey in a straight line to Bagan Jermal, alongthe western shores of Province Wellesley, to an obelisk at Kagan Luar, and ina straight line to Penang bridge, thence aleng the eastern shores of Prince of Wales' island, to the obelisk at Klarwey, including the mouth of Prangin river, as far as the second Teetee Papan bridge, including the public streets, roads, or high ways, made or to be made, along the banks of these rivers, to the limit specified and including all public landing-places, stairs, piers, or jetties, made or to be made, along the shores of the Prince of Wales' island, or that part of Province Wellesley included in the limit ofthe Port. The limits of the South channel are as follows : - From the north bank of the Penang river to Nos. 3 and 5 red buoys, from thence along the eastern bank of Pulo Jerajah to the south-easternmost point of Pulo Rimo, thence in a straight line to No. 9 white buoy, then passing close to Nos. 8, 7, 6, 4, and 2 white buoys, and in a straight line ending at the obelisk built at Bagan Luar.

8. On being boarded by an officer of the Marine Department, every master of a vessel is to fill up the book handed to him, and is at the same time to give a correct list of all the passengers on board.

4. Masters of vessels lying at anchor in the harbour of Penang, on board of which a fire breaks out, are directed to make the following signals without any delay . - In the daytime, the Commercial Qode signal of distress indicated by ""NO;" at the same time, when possible, two guns should be fired, at an interval of one minute; at {night time, two rockets fired, and two blue lights burned alternately at an interval of one minute, and two guns fired as in the daytime. Masters of all vessels are also cautioned, when signallising for assistance, not to forget to take every precautionary measure to put the fire out, and to prevent it spreading.

5. Masters of vessels requiring the assistance of the Police while in the har- bour are to make the following signals: - In the daytime, the national ensign to be hoisted at the main-masthead; at night, one gun to be fired, and one blue light burnt.

4s ADDENDA.

6. Masters of vessels are prohibited from anchoring abreast the jetty or in any place within 250 yards on either side thereof.

7. To prevent accident. all vessels anchoring among the shipping in the harbour intending to take in or discharge cargo, or remain upwards of 24 hours, are to moor and keep aclear hawse. No sailing veesel is to be unmoored or shifted about without permission from the Harbour Master, and on no account after dark, except in case of emergency. Singapore, June 21st 1873. Page 489

PORT LOUIS (Mauritius). - Zhe red light at Great River bay, and the green light at fort George, Tonnelier island, have both been discontinued.

A lightvessel bearing a flashing white light, visible 9 miles, is moored at the Bell-buoy anchorage. It is in 15 fathoms at a little to the north-westward of the present well-known bell buoy, and from it the extreme of the land to the north- ward bears N.E. by N.; the extreme of the land to the westward W.S.W.; and the flagstaff on fort George S.E.4$ 8. As the mooring chain of the vessel runs about 150 fathoms in a N.N.W. direction, care must be taken when anchoring to avoid hooking it.

In the event of its being necessary to take the lightship into port for repairs, or should she be absent from her station for any other cause, a vessel will be anchored on the spot, and will be distinguished as follows : -

During the day - Two flags, white, with blue cross and a ball below each, on two separate masts. During the night - Two signal lamps, one on each mast at the same horizontal height, and a blue light or a flare up light every half hour.

Directions. - Vessels from northward, after rounding Canonnier point, must be careful not to bring the lighthouse on that point westward of Flat island light- house till this lightvessel is seen. They may then steer for the latter on a S.S.W. 4 W. bearing, and anchor on that bearing at from half a mile to a mile from the light.

Vessels from westward may steer for the lightvessel on an E. by N. 3 N. bear- ing, and anchor either at half a mile from it on that bearing or further to the northward as may be convenient. The depth at the anchorage is from 12 to 20 fathoms. Pages 528 - 530.

EAST COAST OF MADAGASCAR. - The following remarks are abridged from a paper by the Rev. J. Holding descriptive of the province of Tanibé, on the east side of Madagascar. As the various towns and villages mentioned lie on the sea-coast, these notes will be acceptable to mariners : -

Tamatave, the chief port of Madagascar, stands on a point of land at the west end of Tamatave bay. The town is much better built than most of the Malagash towns, and is at present divided into streets. There is no pre- tension to architecture except amongst the foreigners. The Malagash have no public buildings except the battery, which is a rude, square, heavy building, at the north end of Tamatave, and at a short distance from the town itself. It is built of stone unhewn, and plastered over with mortar made from coral, which is abundant along this coast. The sides are perforated for about eight guns, three only of which are really serviceable, and now only used in firing salutes.

- The chief exports are bullocks (30,000 per annum), rice, fowls, and hides. For the Mauritius and Bourbon markets there is an occasional cargo of gum and

ADDENDA. xli.

india-rubber, also tobaccu. The imports are manufactured goods - such as cottons, iron-pots, clothing, and house-furniture; also rum and other spirituous liquors; beer, porter, liqueurs, wines, &e. It is not unusual for traders to barter their rum for cattle. A fat bullock costs on board between 14 and 15 dollars, and is sold in Mauritius for ne or 35 dollars. Wood is not permitted to be exported.

The chief employment at Tamatave is mat-making, rice-bag making, fancy boxes, cigar-cases, which employment is altogether confined to the women, who earn about sixpence a day each, which is quite adequate for their maintenance. Two-pennyworth of rice will support one person, and the rest goes for bouillon and betsa-betsa, a drink made from the sugar-cane, and toaka (rum).

The men are usually engaged in fetching rice, wood for building, and cattle and poultry from the country, to supply the market and shipping; others in pounding rice (cleaning it of the husk), fishing, labouring for the Europeans, or engaged in what is called the *"'Fandroana," or queen's service, - making im- provements about the battery or the Hovah town. They are liable to be called upon at any time to perform this service, for which they receive no pay, and not even rations frequently. Jiven the servants of the white traders may be caught by the Hovah "police" if seen in the streets, and forced to labour. It is of no use resisting: the answer is, " It is the queen's service," and all are considered slaves to the queen. If you ask a Malagash who is his master, if he is free, he will say, the queen; if a slave, he will give you the name of his immediate owner.

The country to the west of Tamatave is a dead, unbroken level, a vast plain about five miles inland, southward to Hivondro, and north to Ampangalana. The streets are even and regular, but most disagreeable to traverse, on account of the great quantity of sand. Lach foreigner who intends'to make Tamatave his home for any lengthened period, sets about building a comfortable house, with verandahs to screen him from the scorching rays of the sun; fruit trees are planted all around in his compound, and in time his home becomes really luxurious. .

Hivondro lies about 8 miles south of Tamatave, and was ta dwelling-place of the old princes of the Betsimisaraka.

Hivondro is important, not only on account of its historical connections, but on account of its position on the river Hivondro. This river is navigable for many miles inland. It is also connected with the southern lakes, and is on the road to the capital, Antananarivo. Hivondro presents a curious spectacle in' the rice season. Along the banks, or mooring-places for the canoes, we see representatives from various provinces - the Betsimisaraka, Betanimena, and Antimoras and Antisakas. The Antimoras and Antisakas, with their round skull-cups made of rice-straw or grass, such as we see the lower class of Maho- medans wearing, and the Antisakas from the district south of Manangary are there, looking more savage and wild than any. I have seen some two hundred canoes lying moored here at a time, each canoe containing upwards of thirty-five bags of rice, and each bag weighing 100 lbs. This rice is landed at Hivondro, and conveyed thence to Tamatave, to supply the rice-vessels trading between this island and Mauritius and Bourbon.

The town consists of one long narrow street, running parallel with the arm of the river which comes from the north. The houses on the whole are well built

xi. ADDENDA.

- much more so, I think, than most Malagash houses. There is here a chapel belonging to the Church of England, at the north end of the village, directly facing the road leading into the town from Tamatave. The district round Hivondro is very bleak and uninteresting ; sand-hills rise from the shore, and, to a certain degree, screen the town from the strong breezes which blow from the S.E. in the hurricane months; but their position is manifestly unfortunate in another sense, for the very breezes which might be destructive in one way, would in another be most beneficial in blowing back the dreadful effluvia which the land-breezes bring from the jungles, swamps, and marshlands on every side the broad river. The country inland is very flat for some miles along the valley of the river until we reach Mawasoa.

Ampalamasina is a village in the interior west from Tamatave. It stands upon a high mountain and is reached by passing through a most interesting country, quite refreshing to a foreigner who has been living along the coast some time. The air is bracing, and there is no fever. The village is named from there being in it a huge boulder, which is reverenced by the people in the neigh- bourhood. The hill sides are covered with various kinds of trees and shrubs, and there are a great number of ferns. In one of the valleys I saw a group of splendid fern-trees. The scenery about Ampalamasina is magnificent; splendid valleys; stupendous mountain cliffs, rugged and precipitous ; beautiful cascades; varied tints of foliage - gorgeous brilliancy of flowers. The village consists of one main street and of about thirty-two houses. The prospect from the summit is grand - huge black mountains stretching away inland, and running in one unbroken line to the district opposite Hivondro. The highest peak is about 2800 feet high, and from it may be seen Tamatave, Foulepoint, Vohidoity, and Ifontsy, and the country south of Hivondro. The sea is distant ina direct line about 32 miles. This seems tome a delightful sanatorium for fever- stricken white men.

Vohidoity, a village about 9 miles north of Tamatave, is a miserably unhealthy place on the bend of the river Vohidoity, just where it commences to wind along the coast for about half-a-mile, when it enters the sea. The village itselfis a little elevated, some 80 feet above the river, while below and on the whole western sides are stagnant lagoons and fever-breeding jungle, the usual haunts of crocodiles; in fact, these amphibious animals are so numerous here, that after sundown no one dares to go near the stream, and any unlucky traveller who arrives here after sunset must perforce content himself with staying in this wretched village, sleeping in a miserable hut, and inhaling the noisome pesti- lential vapours.

The river is broad and deep, and well stocked with a variety of capital fish, which the natives catch in baskets and with nets. There is a bridge of rough shapeless wood across one branch of the river which leads into the road con- ducting to the north side of the village; anda few yards outside the town, on the road to Foulepoint, is a tomb of some former chief. Near this place the indigo plant grows very luxuriantly in a wild state.

Ifontsy. - The next village of any importance is Ifontsy, which is about 14 miles north of Vohidoity. It stands on the east side of the island which bears the same name, and which is formed by the confluence of two unimportant streams, one coming from the south-west and the other from the south. This district derives its name from the trees, called Ravenfotsy, which grow in great

ADDENDA. xliil.

numbers in the vicinity. There are no large houses, unless we except the one belonging to the Custom-house official at Tamatave, who has much land: and many slaves in the neighbourhood. TIfontsy is the stopping place between Tamatave and Foulepoint. There is here a Queen's house for the use of travellers, and a flag-staff at the end of the village. The white flag is hoisted when any officer of distinction passes through. The village is very neat and dry, but far from being free from fever, which is generated in the neighbouring swamps and jungles. A sail round the islandin acanoe is quite a treat; and the variation of the foliage from the overhanging woods is quite delightful. I found some very magnificent ferns in this neighbourhood. The country between Ifontsy and Foulepoint is very beautiful until the stagnant lagoons in the immediate neighbourhood of the latter place are reached.

Foulepoint is a town lying about 37 miles north of Tamatave. It is irregu- larly built, with narrow streets. and the native name is Mahavelona. It is a tolerably safe port, and during the fine season, when hurricanes are rare, vessels can be moored opposite the custom-house. The anchorage is good and firm, and vessels of any tonnage can be admitted into the roadstead. There is a huge reef, extending a milé seaward. parallel to the coast, which is dry at low water. Many fine cocoa-nut trees extending along the coast, and mangroves here and there.

Foulepoint is almost surrounded with stagnant lagoons, stretching from the river Hiarana to the outskirts of Mahambo, a distance of 19 miles. These lagoons are well stocked with crocodiles, some 16 feet long, which are so audacious as to approach even the town itself, carrying off pigs and young calves. In fact, after a certain hour at night, the passage between the Betsimisaraka town and the Hovah village near the battery is not safe for any one to travel. It is not unusual, when passing up the river Hiarana, to see at least a score of these horrid brutes basking on the banks, in the short distance of 100 yards. Their eggs are seen lying on the sand on either hand. The natives have the greatest horror of them, yet withal reverence them. The odys, or charms, are composed of crocodile's teeth, intermixed with small portions of their ancestor's bones. These charms are always carried about with them; the ampi sikidy having sold or prepared them, they are considered as talismans against any danger. They are generally worn about the neck, ancles, or wrists.

The town of Foulepoint may be said to be divided into two parts; the portion occupied by the Betgimisaraka and Hovah traders is called Wahavelona, and the town surrounding the battery which commands the roadstead and Betsimisaraka town is called Antanava or Hovah Town. In the first, the poor Betsimisaraka dwell and carry on their various avocations; here also the Hovah and foreign traders reside, and several Hovah officials are in command of the " police." The chief of the custom-house also resides here. The foreign traders live as near the sea-side as possible; in fact, the whole extent of land bordering on the coast is occupied by them, except a small portion surrounding the custom-house.

The Hovah traders do the retail trade. About 2000 bullocks are exported every year, and about 180 tons of rice, while in return they receive about 560 barrels of rum, or 27,000 gallons. The rum is carried into the villages in the interior, and sold retail by the Hovahs; for one barrel the trader will receive two bullocks. Rice-bags and mats are also exported. The means of subsistence

xliv. . ADDENDA.

are similar to those of the people of Tamatave, and the occupation the same. The trade of Foulepoint is evidently declining, and that of Mohambo is increas- ing; the cause of this is the fever, which prevails here during the greater part of the year, and is most destructive to the life of the Europeans.

Iahambo is the port of the Antsianaka nation, and there is no doubt that in time it will become an important rendezvous. There is good anchorage and deep water, and the place is much healthier than Foulepoint. At present rice is much cheaper here than at any other port, but this may be owing to the fact that there is no competition. The town or village consists of one long narrow street, beginning at the beach and leading to the battery, which is built of red sand- ' stone and mounted by two small guns. It isa rude structure, uncemented by mortar, and of a circular form, with locp-holes for the centries. The governor's house is outside the battery, and the soldiers reside in the immediate neighbour- hood, in wretched leaf-huts. Three traders live here; one exports rice and bullocks, another rice and tobacco, and the third (French) salt pork and beef, and hides. Rum and cottons are the principal imports. There isa rivalry springing up between this place and Foulepoint, and, as before observed, the latter must give way - not only on account of health, but because there is every facility for reaching the interior; in fact this port commands the province of Antsianaka which is rich in cattle and rice, while the province of Betanimena is becoming impoverished. As far as the anchorage goes, Mahambo is by far the best; for, ifa heavy storm comes on, the land jutting into the sea at Foulepoint is fre- quently washed away, and renewed in another position. I have seen the point washed away twice in three years! The road from F'oulepoint to Mahambo is much pleasanter than from T'amatave to Foulepoint; we have to pass through a splendid wood about half-way. It is very refreshing to leave the sea-side, with its heavy sand, its rolling surf, and glittering spray, to range through green meadows, and experience the cool temperature of the woods, after the burning heat we have had along the sands. The landscape around Mahambo, too, is much prettier. The hills advance nearer to the shore, and are covered with

wood ; rivulets flow across the plain, first rippling down the hill-side, and at length emerging from the shadows of the woods, glide in smooth and shining

streams across the fields and plain into the sea. There is a coral barrier-reef extending along the coast; this is the only place where one can safely have a sea-bathe. The sea at Tamatave and Foulepoint swarms with sharks; but here on the soft sands, when the tide is up, one can shelter behind the inner barriers, and enjoy it to one's heart's content.

Fenoarivo. - This town is about 12 to 14 miles north of Mahambo. The road to Fenoarivo is partly along the coast, and partly through meadows and woods. The sea-coast here is much more elevated than the rest of the coast from Hivondro to Mahambo, which is really one dead uniform level. When Fenoarivo bursts into view, a long large bay is observed, running to a sharp point of rock, on which the Hovah flagstaff stands, with its white ensign fluttering in the breeze; then widening gradually as it extends along the coast, until the beach is lost sight of in the rugged mountainous region of point Zarre. An island stands at the south end of the bay.

The town of Fenoarivo is irregular, as are most Malagash towns. There is . only one mainst + it leads to the battery and along the banks of the river Fenoarivo. There is a small custom-honse near the river. The whole, or nearly

ADDENDA. xlv.

the whole trade of Fenoarivo is in the hands of Mr. De Castelle, who has large plantations of rice and coffee on the opposite bank of the river, stretching as far as the village of Soavola, where most of the labourers reside. I visited these plantations, and found them in excellent order, exhibiting taste and thorough practical knowledge. The coffee-trees seemed very vigoroys, and the soil well adapted for their culture. On the way back I visited the European cemetery ; it is a wild, neglected place on the borders of the sea; the beach here is com- posed of black sand.

The road to the "battery" leads through the town, and through pleasant meadows, beyond which a swamp extends to the north, and ends near the hills . 'about 5 or 6 miles distant in the interior. The road to the Hovah town leads across this swamp by means of a narrow wooden bridge. It is not by any means a safe mode of travelling. At every step there is danger of falling headlong into the dismal miry swamp below. As soon as the swamp is crossed, there is a circuitous pathway among several small steep hills leading to the Hovah town. From the Governor's house, the whole of Fenoarivo is seen, with the bay. The mountains running parallel with and near the coast, and stretching northward to the river Manaugoro, are also seen to great advantage.

In passing through Fenoarivo I saw the butchers' stalls, or rather the place where butcher's meat is sold. The carcase lies on clean mats, spread out on the ground. There is only one killing day in the week here, the demand for flesh being almost entirely confined to the white traders, who are frequently the only people able to purchase it. The natives are satisfied with rice and occasionally a fowl, or such fish as are caught in the river without much exertion. At Foule- point they kill twice a week, at Tamatave every day. The owner of the bullock must first send the choicest piece to the Governor of the place before he can sell any to others. This is called the queen's beef, and is really a government levy.

The English Church is the only religious body having any place of worship here. It has a temporary chapel in the main street, which cost 14 dollars - a portion of which was contributed by the native Christians.

F'enoarivo is much healthier than any of the other ports in this province. Indeed, the European trader may remain here during the entire fever season without suffering much from the effects of this dreadful scourge. The ground is not so damp, and the elevated position of Fenoarivo lifts it out from the surround- ing lowlands of pestilential swamps, and, to a certain extent, from the influence of their deadly miasmas. The anchorage of Fenoarivo is good, but the bay is much exposed to east winds, and occasional hurricanes, which visit the coast of Madagascar during the months of January, February, and March.

Tamatave contains 8000 inhabitants; Foulepoint, 1500; Hivondro, 900; Fenoarivo, 800; Mahambo, 400; Mahasoa, 280; Vohidoity, 360; Ifontsy, 180.

Fiwers. - The rivers in the province of Tanibe are the Hivondro, Vohidoity, Rangazavaka, Ifontsy, fHiarana, Paombé, Mahambo, and F enoarivo; of these the Hivondro and Paombe are the largest ; none of them are navigable; in the dry season their embouchures are stopped up, and the surrounding country is one mass of mud and alluvial deposit, left during the inundations in the rainy season. Frequently, when the rainy season commences, they change the place of embouchure. When the rainy season commences a fearful scene is presented,

even after two days' heavy incessant rain - the hanks ca rees come rushing down with the torrent, navigation by canoes rendere le ; the

xlvi. ADDENDA.

surrounding country is inundated, the people only saved from being washed away by building their houses on the highest points near the river. The rise is sometimes 20 to 30 feet, and the water may then fall in a few hours to the level of the natural bed. Another obstacle to navigation, besides the bars at the mouth, is the frequency of cataracts - some very beautiful and lofty in their falls, others broad and shallow. The volume brought down by these cataracts after a storm is sometimes tremendous. None of the streams are fordable; but they are much shallower beyond the cataracts, as a matter of course. :

Lakes. - The lakes are merely lagoons of stagnant water, filled during the rainy season by the surplus waters from the rivers. These abound in the neighbourhood of Foulepoint and Mahambo; hence this is the district which is most addicted to fever and malaria. The rivers and lakes abound with fish of various kinds, all agreeable to the palate, and proving a luxury not only to the natives but to the white man who may sojourn there. The finest is similar in character to the salmon, but called zampuna by the natives.

Mountains. - The mountains of this province (Tanibé), which borders on the sea, are insignificant. From Hivondro to Fenoarivo the land does not begin to rise until 24 miles from the coast. In the neighbourhood of Tamatave the hills are more distant still - about 6 miles. Near Fenoarivo the coast land is bolder and more defined - huge rocks jutting into the sea. Approaching inland the hills rise gradually until they attain the height of nearly 3000 feet above the level of the sea. Each range runs parallel to the other and longitudinally with the coast, and each is separated by a narrow and beautiful valley, through which a stream meanders to its confluence with some larger stream, and flows onward to the sea, or forms stagnant lagoons in its course, encircling the rice fields. The coast land from Mananzari, in the province of Antimora, in the south, to Marancetra, in the province of Antavaratra, north, at the extremity of the bay of Antongil,is one huge belt of morass, and lagoon, well stocked with many varieties of fish, harbouring many beautiful and rare water- fowl, and abounding with crocodiles. To gaina distinct idea of the disposition of the mountain-ranges in Madagascar, we must set out from the dead and uniform level of the sea-coast, and lands stretching several miles inland, till we come to the foot of the first range of small hillocks of red sand, surmounted with bananas and other endogens; when we arrive at the summit of these, we generally find a village of some eight or ten houses We see behind us the surf dashing on the shore, deafening with its roar; around us on every side rice fields and herds of cattle feeding; before us inland, at no great distance, a fresh and higher range of hills, approached by a circuitous path, rising gradually, making terraces as it were, almost imperceptibly. When we reach the summit of this range we see behind us the stream we have crossed in a canoe, winding about lazily in the valley below - now swollen and wide by the heavy fall of rain, or nearly dry in the hot season. The small hills we have crossed are meagre, and do not show much above the dead level. We see béfore asa fresh range to climb, which is easily done, and then commences a range of mountains much drier and harder under foot, more solid in their formation; we still see the ocean. Twenty-five miles inland we cross another range, formed of harder substance still, of quartz rock, with crystal shining here and there. As we blinded with the dazzling rays of tho sun shining on its

ascend W surfac ] dian Ocean is seen, and still we hear its roar, though faintly

ADDENDA. -~ Rit

now. We have'no deep valley to cross before we reach the base of the next range; only a slight fall on-the inland side, and we commence to climb another and loftier hill, and we' are now upwards of 1800 feet above the sea-level, but apparently not more than 400 feet from the base of the mountain on which we stand; and so on until we reach the highest range in the centre of the island, where the various ranges are seen lying below on both sides and descending in terraces to the sea. The highest peak is near Ampalamasina, about 2870 feet above the level of the sea. Page 544 - 560.

MARIE BUGENIE BANK (Madagascar). - This bank situated 6 miles off the east coast of Madagascar, N. 38° E. from Nossy Alana or Plum island, and S. 28° EK: from the Mamelles de Natte, has recently been examined by the French steamer Prégent: the reported soundings of 3% fathoms has not been found, but there are several coral patches with not more than 5 fathoms water, - thus verifying the existence of the bank. (1866). Page 550.

FARQUHAR ISLANDS. - These islands were visited in 1867 by M. Lieutard of the French marine. The hill at the-north-west end of the largest and northernmost island, according to his observations is in lat. 10° 7' S., long. 51° 13' 14" E.; the latter is dependent upon the position assigned to St. Paul, Reunion.*

The north point of the island (near which is the only anchorage possible during south-easterly winds, the prevalent winds in these parts) is terminated by a reef. Upon this point there is a hill, which is conspicuous from a moderate distance by a white spot in its centre ; this hillresembles an islet when first seen, at the distance of about 8 miles, but a nearer approach shows it to be attached to the north point of the island, and at the same time land more extensive than it will be seen behind the southern reefs.

The anchorage is in 1} fathoms at about a mile from the land, in the direction of N.N.W. from the hill. In this position the south part of the hill will appear in one with the north part of the most northern hill of the south island.

When seeking the anchorage either from northward or southward it is for the hill at the north end of the island that a shipmaster should steer. When it bears S. by E., a course may be shaped for it, until distant about a mile from the land, when the best anchorage in the vicinity of the islands will have been attained.

Approaching the anchorage from westward, the hill will be seen in the form of an islet, with a white spot on its north face. Great care is required to give a good berth to the southern reefs and also to keep a good leok-out fcr other dangers, because according to Captain Berloim, who has a thorough knowledge of the islands, a bank of 16 to 18 feet exists at about 43 miles W.S.W. from the south-west point of the south reef.

The bottom near the Farquhar islands consists generally of sand. A prudent shipmaster would not run for the anchorage at night.

The channel into the lagoon formed by the islands and reefs is fronted by a bar upon which at low tide the depth is only 7 to 10 feet. When running in, it is necessary to get as close to the land as possible to avoid the heads of rocks about

* Unfortunately M. Lieutard does not state the longitude of St. Paul, nor his meridian distance. He had two chronometers, which were timed four days, previously at St. Paul.

eb)

xlvii. ADDENDA.

the edge of the reef. At high water, the ebb tide in this channel has a strength of about 5 knots.

Tides, éc., - The tides in front of the bar have been observed to rise from 8 to 7 feet. The flood flows to the N.E., the ebb to the W.N.W. with a maximum strength of one mile an hour, the wind being south-easterly.

The current, which, after passing cape Amber (Madagascar) bifurcates to the _ West and S.W., attains in the vicinity of these islands a strength of 2 to 4 miles an hour, flowing in a westerly direction. Page 565.

SEYCHELLES. - The following observations are furnished by the Civil Com- missioner of the Seychelles islands, Mr. Swinburne Ward : -

The harbour of Victoria is filling up in many places, and the coral all round the Seychelles group is growing with an extraordinary rapidity. Taking the original survey of Captain Owen, executed in 1825, the difference between some of his soundings and the existing ones is very large; more than might have been expected even after so many years. In one spot on the anchorage near St. Ann's island, on the opposite side of the harbour, only 7 fathoms are now found where 14 are marked on the chart. In the inner basin, the triangulation of which was made three years ago by the master of the Orestes, almost on the spot marked as the best and most secure anchorage for vessels of war, and soundings given as 7 fathoms, the coral is now within 2 and 24 fathoms of the surface, not water enough for the larger vessels of the Hast African squadron, such as the Highflyer.

Another instance, or rather a series of instances, will be found on the whole bank extending from Frigate island to Eagle island, the whole of which has much increased, but most markedly when passing half way between Mahe and Silhouette, the ordinary course for ships. In many places, 6, 7, 8, 9, and 13 fathoms only are now found where 39 and 40 are marked on the chart. According to the men who now constantly resort to this shallow portion of the bank to fish, this difference has taken place within the past 4 years, but it probably has only been noticed by them since that date. It is ata distance of 6 milés from Mahé, in the middle of the usual passage for vessels of all classes. Of its actual depth at present I have made certain by personal observation and soundings, but for want of proper instruments I was unable to fix their exact positions on the chart.

It is stated by the captains of the different trading vessels and of the whalers cruising in these waters that the same increased growth of coral is found on all the banks between this and Mauritius. '" Coetivy"" is in reality very much larger than what it is marked on the chart, and the soundings very much less, 7 fathoms only having been obtained for a distance of 20 miles. At this depth in anything like heavy weather, the sea would necessarily break. The '" Fortune bank" has greatly expanded. 'Saya de Malha" is becoming dangerous, and is likely to appear above the surface before many years elapse.

It is very important in the interests of navigation that these waters, especially such portions as are frequently crossed, should be re-surveyed. Of the growth of coral nothing absolutely positive is known beyond the fact that it requires a substantial basis. The bank between Frigate and Eagle islands is part of the Seychelles geological range, and probably, therefore, composed of granite, upon which the coralline insect has commenced its work. This work can be ad- vanced to within 6 feet of the surface, but the progress of its advance is very

ADDENDA. xlix.

uncertain. Still, the well ascertained growth of more than 20 fathoms, as is the case in the channel between Mahé and Silhouette, supposing the coral to have been growing since the date of Captain Owen's survey, sufficiently denotes the great necessity that exists for fresh soundings being taken.

The following sailing directions for the roads and harbour of Victoria, Mahe island, Seychelles, are furnished by W. H. Franklyn, Esq., H.M. Civil Com- missioner, May 1870 : -

Buoys and beacons have been placed both in the outer roads and inner harbours of port Victoria, in order to render the approach to the anchorage for the larger vessels safe and easy by daylight without a pilot. There are no port charges.

Vessels coming in from seaward should pass all chequered buoys and beacons with balls at the top on the starboard hand, and all black buoys and beacons with half balls at top on the port hand. On rounding the northern end of St. Anne's island a red and white chequered buoy with staff and ball will be observed bearing W. by S. distant 14 miles from the north point of the island. Steer so as to pass this buoy on the starboard hand at a distance of about 100 yards; a black buoy with pole and half a ball will then be seen, which pass, keeping it on the port side of the vessel. Two other buoys of the same description and in similar positions will next be passed, and when Beacon island is in line with the southern end of St. Anne's island steer for the entrance of the harbour, which is marked by a large red and white chequered beacon surmounted with a ball on the starboard hand, and a black beacon surmounted with a half ball on the port hand ; pass between them and steer for the anchorage, keeping the red and white beacons on the starboard hand. The best anchorage for large vessels is after passing the third red and white beacon and the second black beacon.

With reference to the entrance of port Victoria, Lieutenant C. H. Taylor, R.N, of H. M.S. Cossack, remarks, that in October .1869, the Fairway house of the charts,could not be distinguished, as it was entirely hidden by palm trees, and that no means then existed of finding the fairway line of approach and entering given on the chart.

This officer reports a shoal patch with 17 feet as lying W. by 8.4 S., about 8 cables distant from the south-west point of St. Anne's island.

Lieutenant Taylor further remarks that vessels bound to the southward from the Seychelles should not attempt to pass to windward of the islands and _ reefs lying between them and the north end of Madagascar, the winds being variable, the weather frequently thick and hazy, the currents strong and uncertain, ap- parently for a great part of the year. The Cossack experienced the strong westerly current very unequally, and twice had to use steam to ensure the safety of the vessel.

Alphonse, the southern island of the Amirante group, he describes as particu- larly dangerous, being low and difficult to distinguish even at a distance of 3 miles. 'There is deep water close to the reef, over which the sea breaks heavily, the surf being seen before the island can be made out. Variation 4° W.

M. Décugis, Master of the Schooner Gilberte, while in sight of Mahe Island passed over a bank which he places in lat. 5 8'S., long. 55° 43'9" HK. The soundings varied from 6 to 10 fathoms in the space of 1} miles. I'rom the mast

d

l, ADDENDA.

it appeared to be round, extending about 2 miles from N. to 8S. _ Pages 576 - 582,

MINICOY ISLAND. - The following account of Minicoy, by Captain J. P. Basevi, R.E., F.R.G.S., is extracted from the Journal of the Royal Geographical Society, vol. XLII, (1872), page 368 : -

Minicoy (strictly Minakai) is a small coral island, dividing the 8th and 9th degree channels in 73° E. longitude. In shape it somewhat resembles a crescent, the concave part facing the north-west; its total length is about 6} miles. The northern half of the island is very narrow indeed, being in no place more than 200 yards broad, but the southern portion is wider and averages 600 yards; the greatest breadth is not more than 1000 yards. The lagoon is on the west side and has a maximum breadth of 3} miles; the reef which encloses it on the west is always bare at low water. The depth of water inside is very variable, but probably does not exceed 8 or 9 fathoms; towards the southern end the lagoon is very shallow.

The principal entrance is at the north-east extremity, where there is a depth of 12 feet at high water. There is no surf on the bar at any season, but the channel is narrow, and there is a disagreeable cross surf on the eastern (island) side, which has to be avoided. here are three anchorage grounds, where vessels drawing too much water to enter the lagoon can lie ; none, however, are good. The Sir John Lawrence anchored in about 15 fathoms off the north-east end of the island, but there is merely a narrow rocky bank here, and it would be unsafe in bad weather. The best anchorage during the North-east monsoon is westward of the reef a little below the middle of the island, where for a considerable space the 'soundings do not exceed 10 fathoms; it is about a quarter of a mile from the reef. 'There is a narrow passage through the reef near, which is used by fishing- boats; it is not more than 12 or 15 feet broad, and about 6 feet deep. The third anchorage is eastward of the island, nearly opposite the village (which is, however, not visible from it), where the depth of water is said to be 20 fathoms. There is a good landing place in jine weather close by, the only possible one on the east side of the island, where the surf is always very high. There is a very small detached island at the south-west end of the main island, half a mile north of which is a third passage into the lagoon; it is of the same description as the second one just described, but still narrower. The rise of tide, at springs, is rather under 3 feet.

The island is elevated only by a few feet above the main level of the sea, and the central parts are, if anything, below that level. Along the east coast, opposite the village, a high bank has been raised for protection against any encroachment of the sea, which the present inhabitants say was built several centuries ago ; the bank is over 20 feet high in parts, and extends for quite 2 miles, if not more. There is a natural bank thrown up by the action of the sea, which is difficult to be distinguished from what may have been artificially constructed. The whole of the island is covered with coco-palms, which are the chief source of wealth to the inhabitants, all of whom have their own trees, the rich as many as 2,000. Away from the village, the undergrowth consists chiefly of a prickly bush which hes a large white flower of a strong but agreeable scent.

The village of Minicoy is situated nearly in the middle of the island; on the west side; it is half a mile long, and contains at least 300 houses, arranged in

a 7 " .

ADDENDA. li.

lanes parallel to the water. The houses are invariably built of coral rock, cemented with lime, and are thatched with palm-leaves; every house stands in a separate compound, the divisions of which are of coco-leaf matting, and the entrances into the enclosures are shut by a hanging mat of the same material. There is abundance of fresh-water on the island, almost every house has a separate well ; it is slightly brackish, but not-at all unpalatable. 'The people asserted that good water could be found close even to the edge of the lagoon. Besides the wells, there are a number of good-sized tanks, revetted with masonry, in different parts of the village. In the northern and southern portions of the island water is only found in a few places. There never has been, in the recol- lection of the present inhabitants, any scarcity of water.

The people are Mahometans, and are of the same race as the Maldives; they speak the same language called Malikh or Malkee, and occasionally intermarry with them. They are now, and have been for the last 200 years, under the Rajah of Cannananore, having voluntarily placed themselves under his rule to obtain protection against the Malabar pirates, who used to molest them. The dress of the men is the same as on the Malabar coast; the women wear a long jacket of a silk material, reaching nearly to the feet. Some of the men do no work, others work as sailors, and fish, but on land do no labour. Every descrip- tion of land work is done by the women, who clear paths through jungle, collect firewood, &c, &e. The population exceeds 2,000.

Behind the village the people have their gardens in which they cultivate plan- tains, limes, betel, palms, pan, the bread-fruit and papaya, and a few vegetables. No kind of corn or rice is grown. All their food (rice, dal, ghi, &c.) is imported. The chief products of the island are coco-nuts, coir, cowries, sugar made from coco-palm toddy, and salt fish. The coco-nuts, coir, and cowries, are generally taken to Calcutta, the salt fish they take to Ceylon. 'Chere are but few animals on the island. The people do not keep cows, sheep, or goats, and no dogs; but they keep cats and have plenty of fowls and ducks. The island is overrun with rats which live up in the coco-trees and destroy, it is said, three-fourths of the produce. There are also legions of mosquitoes which are small but very pertinacious; they bite through anything. Turtle abound but are not eaten by the people.

The climate of the island is said to be very equable. (Pace 589.)

ANDAMAN ISLANDS. - The lighthouse on Table island (one of two islands, Table and Skipper) at the north end of Great Coco island, consists of an iron building 72 feet high; the light (fixed) is 200 feet above the sea and visible in clear weather from the distance of about 20 miles. Its approximate geographical position is lat. 14° 10' 52" N., long. 93° 20' 45" E.

This light, at the southern limit of the Preparis south channel, forms for vessels passing between the gulfof Martaban and the Madras coast, and between Calcutta and the Malacca straits or China, a good point of fresh departure in the South- west monsoon, while the Alguada reef revolving light, placed at the northern limit of the Preparis north channel, is a good point of fresh departure in the North-east monsoon. By shaping a course to make either of these lights, the dangers about Preparis island are avoided.

Vessels using Preparis channels in the South-west monsoon, should endeavour to make Coco light, and in the North-east monsoon, Alguada light; powerful

d 2

li. ADDENDA.

steamers between Calcutta and the ports of Pegu, use the latter in both monsoons.

Table and Skipper islands are steep-to, with no dangers to seaward; there is. a passage between them and Great Coco island, but its navigation is not safe without a pilot. Page 625.

The following Notice relative to the geographical position of the Andaman islands, was issued in March 1866, by Lieut. Col. J. T. Walker, R.E., Superin- tendent of the Great Trigonometrical Survey of India; -

Doubts having been expressed as to the accuracy of the longitudes assigned to the Andaman islands on existing charts, notice is hereby given that the longitude of Chatham island, port Blair, has been recently determined to be 92° 43' E. of Greenwich; whereas in the chart of the Andaman islands, which is compiled from the surveys of Lieut. Blair, and Captain Morrsom, in 1789 - 90, revised by Lieut. Heathcote in 1853, it is assumed to be 92° 56'. The whole group of islands is probably 13 miles west of the position that has hitherto been accepted.

The recent determination of the position of Chatham island is deduced from 202 observations of lunar zenith distances, and 29 culminations observed by Mr. Nicholson, of the Survey Department, with an alt-azimuth instrument, having a vertical circle 36 inches in diameter. They were reduced in the office of the Great Trigonometrical Survey of India. Page 634.

NICOBAR ISLANDS. - The following information relating to the Nicobar islands has been furnished by Navigating Lieutenants John Phillips and W. H. Hayward, of H.M.S. Forte and Dryad, 1871 : -

Car Nicobar, the northernmost island of the Nicobar group is about 7 miles north-east and south-west, and 6 miles broad. The south and south-east ends are moderately high, the north end being low, but in no place less than 60 feet above the sea. 'The island is thickly covered with jungle.

Anchorage. - There is anchorage all round the island, but in rather deep water, except in the bay on the north-west side, known as Saoui bay, where vessels may anchor in from 12 to 14 fathoms, rock and coral with a light surface of sand.

The principal village named Moose is situated on the east side of Saoui bay , near the north end of the island; there is good landing in a cove immediately under the flagstaff recently erected on De Roepstorff bluff; at high water the landing is indifferent.

Tides. - There are regular tides in Saoui bay, the flood running eastward.

Wancowry Harbour. - This harbour, formed between the islands of Nancowry and Camorta, is commodious and sheltered from all winds. It has two narrow entrances, one from the east and the other from the west, and can therefore be entered or left without difficulty in either monsoon.

Buoys. - The eastern entrance is marked by two buoys: a white buoy marks the north-east extreme of the reef off the village of Alla Coango, and a black buoy, with staff and two balls, is placed outside the southern edge of the reef, extending off Naval point. The western entrance is narrower than the eastern, but has the advantage of all dangers being visible.

Directions, - In. coming from the southward and westward, and with the south- east point of Katschal island bearing N. by E., mount Edgecumbe the highest and southern part of Camorta island forming the north side of the entrance to the harbour will be seen. Upon opening mount Edgecumbe, the south side of

ADDENDA. lin.

the entrance is marked by a detached rock, resembling a dog's head, having steep sides and a bushy top, with rocks apparently extending off it.

A vessel should pass midway between Indian and Man points, then steer N.E. by N. up the harbour, edging to the northward as point Leda is approached until Naval point beart E.N.E. when the latter may be steered for. This will lead midway between the reefs off Alfred and Leda points, and on to the anchor- age off the settlement, which latter is on the Camorta side, between Naval and Battery points.

A wooden pier about 7(0 feet long is being built at the settlement and is al- ready about two-thirds finished.

Great Nicobar is the southernmost island of the Nicobar group; at its south end is Galathea bay, a deep indentation of two or three miles in extent, where | there is fair anchorage during the North-east monsoon in from 9 to 16 fathoms.

Upon passing the south or Parson point, off which the surf breaks heavily, a remarkebly flat island named Walker will be seen on the west side of the bay, resembling a fort with sentries posted round. The only landing place bears from Walker island, N.E. by E.} HE. andis on coral slightly fringed with sand, be- tween two reefs. _

Tides and Currents. - When in the immediate vicinity of the Nicobar islands, a ship will be influenced by the tides, the flood setting to the eastward. In the offing the currents as affected by the prevailing monsoon will be experienced, but - they are uncertain in strength and irregular in direction. Page 641 - 652.

CAPE LEEUWIN. - The following information on the current in the neigh- bourhood of cape Leeuwin and Swan river, on the west coast of Australia, during the summer months of January and February, is extracted from the remark book of Capt. Charles W. Hope, of H.M.S. Brisk, 1868 : -

After rounding cape Leeuwin a strong set to the K.N.E. was expéfienced. At Sh. p.m., abreast cape Naturaliste, 15 miles distant, a course was st®ered to pass 8 miles to the westward of Rottnest island; but at daylight Garden island was observed on the starboard bow and Rottnest island on the port bow, the ship having been set 20 miles to the E.N.E. during the night. Had the weather been thick, so that the land or Rottnest light could not be distinguished, the ship would have been in a very dangerous position, as the course steered would have led directly on to the reefs north of Garden island, Pages 232, 652.

GEOGRAPHE BAY. (Western Australia.) - The following information rela- tive to the capabilities of Geographe bay as a secure and convenient anchorage has been received from His Excellency the Governor of the Colony, 1871 : -

Residents of long standing and captains of merchant vessels who have of late years visited Geographe bay agree in considering that it has good and safe anchorages, with smooth water and well sheltered from all winds, westward of N.N.W.: that as an anchorage it is one of the best in Western Australia or Vic- toria, being preferred by them to Freemantle, Macdonnell day, Portland, port Fairy, or Warrnambool, and that ifa vessel be provided with a good ground tackle it may be used with safety both in winter and summer. The depth of water is sufficient for vessels of moderate tonnage, there being 4 fathoms within a mile of the shore, and vessels are easily loaded with timber by the Australian Timber Company established on its shores.

liv. ADDENDA.

Should masters of ships not like to remain at the anchorage off the timber station, the signs of approaching bad weather give ample time for them to run under cape Naturaliste, and find protection in all weathers.

It is farther stated that a reef of rocks crosses Geographe bay from cape Naturaliste to Koombanahpoint, and although the bay appears to lie open to the full force of the northerl, and north-westerly gales, yet through the even nature of the bottom, which is covered with seaweed and deepens very gradually from the beach to a depth of 20 fathoms in a distance of about 20 miles, these winds only create a broken swell not sufficient to wet the flooring of Busselton jetty.

The south-west swell divides between cape Leeuwin and cape Naturaliste, the northern current rushing past the latter cape and crossing Geographe bay intercepts the swell caused by northerly gales. The bay is protected from Castle rock to Minninup by cape Naturaliste, and vessels finding it advisable to seek more shelter during a gale should make for Dimsbro bay, which is also pro- tected by the reefs extending from the cape. The northerly gales seldom last more than 6 or 8 hours, and then veer to north-west.

Busselton jetty runs in a north and south direction, and is fully exposed to the force of the northerly winds, its platform being only 8 feet above the sea. Coast- ing vessels have remained at anchor off this jetty in perfect safety during the most severe gales. |

The brigantine Odalisk lay in Geographe bay through the winter of 1869, and only on one occasion had to let go a second anchor. Several stiff gales were experienced, but the sea never came in heavily.

In June, 1867, the Odalisk ran inside cape Naturaliste in a strong gale from West and W.N.W., and anchored about 6 miles south-east of the cape in smooth water.

The Hliza Blanche put into Geographe bay for shelter three times in 1870, when on her passage from Adelaide to Freemantle.

Geographe Bay is wide and deep, the soundings decreasing from about 18 fathoms near the centre of the bay, to 38 fathoms, at one mile from the southern shore.

This southern shore is low and sandy, and off it vessels employed in bay whaling and in embarking timber, find good anchorage during the greater part of the year, notwithstanding their exposure to the north-west winds of the winter months. 2

Busselton, - The anchorage chiefly resorted to by shipping in Geographe bay is in 8 to 5 fathoms water off the mouth of Vasse inlet and the small town of Busselton.

At half a mile northward of the town there isa narrow strip of weeds, with only 9 feet water over them; but the water deepens to 3 fathoms close to the northward of this strip, and to 24 fathoms towards another weedy bank which extends from the shore.

Approaches to Geographe Bay, - Cape Naturaliste, the western headland of Geographe bay, is low at its extremity, but soon rises to an elevation of 500 or 600 feet, its rounded summits appearing smooth and inuch wooded. The ex- tremity of the cape is closely fronted by rocks.

Pioneer Reef is said to lie 4 miles to the northward of cape Naturaliste, heavy breakers having been seen in that position by the Pioneer, American whaler, in a light breeze after a heavy gale in 1838. H.M.S. Beagle, in 1842, passed close

Ee ae ae ee UU

< ? y : ' *]

ADDENDA. ly.

to the spot, and saw no appearance of the reef, although aware of its reported existence. From the soundings being very regular in 25 or 27 fathoms, it is supposed that the broken water seen by the Pioneer was caused by the meeting of the swell from the S.W. with a strong southerly current sweeping out of Geographe bay.

Wright Bank, said to be a patch of rocks with 5 or 6 fathoms over them, is reported to have been sailed over at about 14 miles to the northward of cape Naturaliste, by the Samuel Wright, American whaler. The Beagle, on the fore- going occasion, passed at about a mile to the north-westward of its supposed position, with regular soundings in 27 fathoms, without any appearance of shoal water.

Waturaliste Reef lies N. by E. 16 or 17 miles from the extremity of cape Naturaliste, and consists of three patches of covered rocks extending about 14 miles, N.E. by E. and S.W. by W., with passages between them. The sea does not always break on this danger, nor do the soundings afiord any certain warning in approaching it, the average depth of water being 25 to 30 fathoms at 5 or 6 miles to the westward of the reef; and there are 13 fathoms at one mile to the northward of it.

Naturaliste reef, and the supposed Pioneer reef, and Wright bank are the only dangers reported to exist in the vicinity of cape Naturaliste. Variation 5° W. (1871). Page 653.

PORT GREGORY. - Lloyd's agents writing from Freemantle, Western Aus- tralia, 10th November, says - A report having reached us that the master of a ship has been instructed to proceed to Port Gregory to load ore, we deem it our duty to report, for the information of Underwriters, that Port Gregory is not a fitting place for any but very small vessels to enter, and it is a most dangerous place even for small vessels. Page 655.

_ROTTNEST IsLAnpD. - The following information on the navigation of the approaches to the Swan river, Western Australia, is from the remark book of Staff-Commander William H. Bradley, of H.M.S. Galatea, 1869 ; -

The pilots report Roe reef, with a depth of 24 feet, to extend farther to the westward than shown on the charts.

A 15-foot patch is also reported to exist on the northern extreme of the bank outside the Transit recks; Bare hill well open northward of Ropeyarn rock (the rock westward of Duck rock) W. by S. } S. is the mark given to clear it.

A 19-foot rock is said to have been found on the tail of the bank that extends E.S.E. from Phillip point. A vessel coming in from the southward may pass between it and the Pilot reef by keeping the knob of Parker point touching the south end of Direction island until the pilot house on Bathurst point is open northward of Philip beacon, when she may haul to the north-east until the Winding sheet (a bare sand-patch on the mainland) bears E. } S. and then steer in for it. These directions lead over the bank in not less than 5 fathoms, and clear some patches of 21 feet which lie to the eastward of the 19-foot rock.

Another bank, with'15 feet water extending north and south one-third of a mile long, is reported to lie W. by N., about 1? miles distant from the Winding sheet sand-patch.

The Challenger pass, between Garden and Carnac islands, is not recommended for any class of vessels.

vi. ADDENDA.

The Success beacon has been removed from the southern edge of the Success bank. Variation 5° 30' W. Page 656.

BEAVER REEF. - A bank with 20 fathoms water on it has been discovered some 50 miles to the west of Rottnest island, and breakers were said to have been seen in 1864 from the Beaver, merchant vessel, W. by S. 52 miles from cape Vlaming, the west extreme of Rottnest island.

The existence of this reef has been confirmed by Captain Laing of the schooner Gift, who passed it on the 15th of April, 1869, when the sea was breaking heavily and continuously on the danger.

The reef appeared to extend about half a mile North and South; soundings were obtained in 15 to 18 fathoms, a quarter of a mile from the southern end, and its position agreed with that assigned to it in 1864, viz., about 52 miles W. by S. (true) from the west end of Rottnest island, or in lat. 32° 8' S., long. 114° 82' E., approximately. Page 656.

POINT CLOATES. - Information has been received of the existence of a sunken rock on which the ketch Strathmore touched. This rock has about 8 feet water on it and is situated about 12 miles West from point Cloates, and therefore approximately in lat. 22° 37' S., long. 113° 24' E. (1873). Page 665.

PORT DARWIN. - The following remarks on Port Darwin, are from a report by Captain Van der Gevel of the Dutch ship, Maria ELlzabeth : -

When once inside, Port Darwin is seen to be a most splendid harbour, sheltered from all winds and having no sea whatever; a dock can be made there, at very little cost, large enough for the Great Eastern, owing to the favourable nature of the tides. At present (1871) the delivery and landing of cargo is still very wearying and tedious for ships' crews; the cargo has to be landed in boats belonging to the ship, for there are no others, excepting a small cutter which may now and then be made use of by way of favour from the Resident. Labourers cannot be obtained, for the natives will not work, but earn their live- lihood by the spear. As to the Europeans, all are in the employment of Govern- ment. Port Darwin is in great want of coolies.

The following information relating to Port Darwin, with instructions for anchoring clear of the ocean telegraphic cable laid between it and Java, are from Lieutenant B. Douglass, R.N.R., the Government Resident, March 1872 : -

Port Darwin is a free port; neither customs duties nor harbour dues are imposed. A shipping-master is appointed for the shipping and discharge of seamen under the Marine board Act of South Australia. The commanders of Australian ships are, however, required to report and clear their ships in the usual way before the custom house oflicer, and a correct account in the form of entry must be given of all goods landed, although no import duties exist. A magistrate's court exists, and a body of mounted police are stationed in the territory.

Position. - The flagstaff at Port Darwin stands on Fort hill on the northern shore, and is in Lat. 12° 28' 28" S., Long. 180° 52' EK. Lhe Commercial Code of ~ Signals is in use at this station.

Pilot - When a vessel heaves in sight, the Harbour-Master and pilot will board, and bring her into the anchorage.

Anchorage.- - The best anchorage is off the south side of the little valley

™_

ADDENDA. lvii.

between the table land of point Emery and Fort hill, not coming under 7 fathoms at low water in a large vessel, nor under 6 fathoms in a small craft. Ships remaining more than two or three days should moor with open hawse to the north-west.

Great caution should be observed in taking up an anchorage near the line of the cable during the strength of the tides, as the soundings are deep, and ships sometimes drag before bringing up. Tlis caution should be specially observed during the North-west monsoon.

The Tides in the vicinity and in the harbour of Port Darwin are rapid and somewhat irregular. It is high water at Port Darwin, full and change, at 5h. 25m. Springs range from 16 to 24 feet; neaps, 2 to 12 feet. The ebb stream makes 40 minutes before high water. Outside the harbour the flood runs from the north-westward and the ebb from the E.S.E.

Landing Place and Direction of Telegraph Cable- - The shore end is landed on the mud flat below the Residence, on the east extreme of the table-land on which the town stands.

At about a cable from the edge of the flat, the telegraph cable runs W. by N.3.N. for about two miles, when the north extreme of point Emery bears N.E.3N., and the base of Fort hill, on which the Hagstaff stands, bears E. by 5.35.

From that position the cable lies in a N. by W. direction, running parallel to the point Emery shoal for 3 miles, when the extreme of the cliff of point Emery bears S.8.E. and East point N.E.}E. It then takes a W.N.W. direc- tion for 24 miles, when the south extreme of East point bears E. by S. 4 S., and Tale head S. by E. From the above position the cable is laid about N.W. 3 W. for 11 miles, when its course is changed to W. by N. 3 N. into the offing, and in soundings beyond the depth of 14 fathoms.

Directions - When off the coast line between Fort point and point Kmery, and in the vicinity of the ordinary anchorage off the town, to keep outside and clear of the cable, keep the extreme of the land of the West point at high water mark N.W. by W. 4 W., and the summit of Tale head from W .} S. to S.W. by W. 3 W.

Off the coast line between point Emery and East point, keeping to the west- ward of the cable, keep the summit of King's Table S. 3 E. until East point bears N.E. 3 E.

In the offing clear of the harbour, to keep south-west of the line of cable in about 12 fathoms, keep the south extreme of point Emery 8.E. } E. until the West extreme of the land about point Charles bears 8. by W. + W.

It is not recommended to navigate inside the line of cable between Emery point and East point, as that portion of the coast is much encumbered with shoals. In the offing the navigation is safe on both sides of the cable.

The shore end of the cable, which is carried out to the north of point Charles, is very heavy, and could not be lifted by any small craft, though it might be injured, and commanders and owners of ships are subject to heavy damages if the cable is negligently fouled. Page 666.

KING GEORGE sounpD. - The fixed light on Breaksea island is visible by a

vessel approaching from south-eastward between Bald head and cape Vancouver

(S.W. 4S. southward and eastward to E. by N. from the light); approaching

lvii. ADDENDA.

from south-westward, it is first seen for a brief interval over the sinking of Bald Head ridye (S.W. } W. from the light). Within the sound it is shown over the horizon (60°), but is masked by Michaelmas island to a small vessel passing through the north channe}. This light must not be steered for till it bears N.N.E. 2? E. from the vessel, to clear Maude and Vancouver reefs. Page 671.

SPENCER GULF - Tipara Lightvessel. - The lightyessel on Tipara reef, east side of Spencer gulf, now exhibits a fived white light, 35 feet above the sea, visible about 10 miles.

Tipara Reef. - A rocky patch, having only 12 feet water at low spring tides, lies N.W. by W. 13 miles from Tipara lightvessel. It is marked by a buoy placed outside (to the westward) of it. The buoy, chequered red and black, is moored in 4 fathoms, and its approximate position is with the Tipara lightvessel bearing 8... by E. + E., distant 1% miles.

Mariners are cautioned not to approach the reef to a depth less than 7 fathoms, as the ground, to a considerable distance from the reef, is uneven.

Wallaroo gay. - A shoal patch, with only 16 feet at low water spring tides, has been discovered in Wallaroo bay.

A red perch buoy has been placed on this patch with the following bearings : - Extreme of Riley point N.K. by N. (northerly), the Smelting chimney at Walla- roo 8.E. by EH. 4 E.

Note. - Vessels beating up the anchorage with S.E. winds, are recommended not to bring the jetty to bear to the southward of E.S.E. until point Riley is brought to the northward of N.N.E.

A small rocky patch, on which the ketch Dashing Wave is reported to have struck, and having only 4 feet water on it at low water, is stated to exist about N.W. from the Walrus rock, distant a short mile. As this danger lies directly in the track of small vessels trading to and from Moonta and Wallaroo, mariners should be cautious to give the same a wide berth.

Beatrice Rock. - Information has been received from Staff-Commander F. Howard, R.N., of H.M. surveying schooner, Beatrice, that a rock having only 9 feet water on it at low water, with from 7 to 8 fathoms all round it at one cable's distance from its centre, has been discovered, with the following bearings from the rock : - Small islet off cape Donnington, N. 49° W. (true) dis- tant 10°2 miles; highest part of Dangerous reef, N. 68° I. (true) distant 2.8 miles.

A rock, on which the cutter Secret was totally lost, is reported to exist about 8 miles north of Bolingbroke point and one mile off the headland; it lies in the track of vessels trading to and from port Lincoln, Tumbay bay and port Augusta. (1873).

Port Augusta. - Masters of vessels trading to and from Port Augusta are informed, that a cheese-shaped buoy, with beacon top, painted red, has been placed on the edge of the sandspit, to the southward of Yatala harbour, in 17 feet at low water spring tides, on the following bearings : - mount Grainger N.N.E. } E., and mount Gullet E. by S.

A red buoy of the same description has been placed on the 8.W. end of Ward's spit, in 18 feet at low water springs, on the following bearings : - Point Lowly N.W., distant 34 miles, and the beacon on the N.W. end of Ward's spit, N. 35° E., distant 14 miles.

ADDENDA. lix.

The nun buoy, on the south end of the eastern shoal, has been shipped to the west side of the shoal, and painted red; it now lies in 21 feet at low water springs, on the following bearings : - mount Young, N. 85° W., and point Lowly, N. 10° E. Variation 4° 40' KK. Pages 672 - 682.

CAPE BORDA (Kangaroo Isianda). - The following instructions were issued by Capt. Douglas, President of the Marine Board, Adelaide, in 1866 : -

Captain Leeor, of the ship, Zhe JZurray, reports that on his passage from London to Australia, at 4h. 30m. a.m., on the 21st of October 1864, running in for cape Borda on an E.N.1. course, with strong $.5.W. winds and thick rainy weather, he saw the land betweeu capes Bedout and Borda, before sighting the light, although, from the course and position (subsequently verified by cross bearings) he should have seen the light at 2h. a.m., allowing for the state of the weather.

At 5h. a.m., after tacking off the land, cape Borda bore N.K. 103 miles, cape Couédie 5.1. by K.; thus putting the ship quite within the range of the light (it being visible from N.E. by N. to S.W. by W. round by west); it was not seen until some clouds cleared off the summit of the care and adjoining land.

The light is placed 510 feet above the sea level, and in clear weather is visible at a distance of 30 miles.

By Gaptain Leeor's report, it appears that, during thick or hazy weather, the light is occasionally partially obscured ; in such weather, commanders of ships should exercise great caution in approaching the land, even when quite confident of their position. No safer guide exists in the vicinity of Kangaroo island than the lead, as by keeping in a depth of not less than 70 fathoms, a ship will be well outside all the dangers off this part of the coast, including the Neptune island group. In fact, in that depth, a ship will be clear of all danger on any part of the coast of South Australia, as included between the Great Australian bight, and cape Northumberland.

During strong §.E. winds, the prevailing easterly current on this part of the coast is checked and diverted to the northward into Spencer gulf, and north- westward along the coast-line; whilst after S.E. winds, and the wind changing to the northward and westward, the current exhibits an unusual force and sets strongly to the S.E., sometimes at the rate of 13 knots per hour.

Commanders of ships, after a prevalence of 8.E. winds, should, on the wind changing to the N.W., be on their guard, as they are liable to be set to the S.E. on approaching the western end of Kangaroo island. Pages 672 - 682.

BACESTAIRS PASSAGE. - The following information has been received

from Captain John Hutchinson, R.N., Admiralty Surveyor, on the Yatala and

Scraper shoals.

Yatala Shoal is 33 miles long, north-west and south-east, by about a cable broad, shoaling gradually from 9 fathoms at its edges to 3 fathoms on its centre. From the shoalest part cape Willoughby lighthouse bears S. by W. 63 miles, cape Jervis N.W. ¢ N. 74 miles, and the South Page E. by S. 4 S. 64 miles.

The Scrapers. - The least water on this shoal is 14 feet, distant 4 cables W.N.W. from cape St. Alban, with cape Willoughby lighthouse bearing S. 3 E.

_ 24 miles. From the breakers on the south-eastern extreme of the shoal, cape St.

Alban bears N.W. 3 W. 14 miles, and cape Willoughby lighthouse S. by W. 4 W. 13 miles. Variation 5° 40' H. (1869.) Page 683.

ix ADDENDA.

ADELAIDE. - The lightvessel has been removed, and instead of it an iron tower has been erected on piles near the end of South sand, in 7 feet water. It is 65 feet high, and shows a fixed light at 50 feet above the sea, visible 10 to 12 miles. The navigable channel for large vessels is 70 yards northward of the light- house; the depth in it at present (1868), is 13 feet at low tides, ordinary springs - the rise is 8 feet.*

Approaching Adelaide from south-westward in a heavy ship, endeavour to make the lighthouse on a bearing from N.N.E. to N.E., and carefully avoid bringing it northward of N. by E. to avoid the Wonga shoal, southward of the jetty. The most convenient anchorage (in 5 fathoms, sand) will be found with the light- house bearing N. by E. to N.N.E.; and the red light on the jetty from E. by S. to E.S.E. Page 685.

The Wonga, a sandy shoal, extends in a north-westerly direction from the sand-hills southward of the Semaphore. A bell buoy painted red (shaped like a boat, with a staff and ball) has been placed in 17 feet at low water, on its northern extremity, off the end of the jetty; it may be seen during day at a distance of 24 miles. From the buoy the water shoals gradually in a south- easterly direction to the shore.

The buoy should be left to the southward and eastward, but small vessels may cross the shoal southward of the buoy in 12 feet water, by bringing the Sema.- phore jetty light to bear EK. by 8S. 3 S., and anchor according to draft of water off the end of the jetty. Large vessels should avoid crossing the shoal southward of the buoy.

The best anchorage for large vessels is anywhere northward of the bell buoy, in 4 or 5 fathoms at low water. Vessels waiting for orders will find it con- venient to anchor tolerably close to the buoy ; whilst those only waiting for tide to pass the bar, should anchor with the jetty light bearing S.E. Small vessels may anchor inside the bell buoy with the jetty light from E. by S. to E.S.E.

It is high water at full and change, at the Outer bar of port Adelaide, at 4h. 30m.; and the rise is about 8 feet. 'Tidal signals are shown from the Sema- phore flagstaff on the hill, but as strangers are required to take a pilot, it is unnecessary to describe them here. The signal for a steam-tug is the ensign at the fore. A signalman is stationed on the hill above the inner end of the jetty, to attend to vessels' signals. (1866). Page 685.

CAPE JERVIS. - A fixed white light is exhibited from a lighthouse, on cape Jervis, at the entrance of Backstairs passage from St. Vincent gulf.

The light tower is in lat, 35° 37' 3" S., long. 188° 7' 30" E., and the light is shown over an arc of 151° (from S. 25° W. westward to N. 4° W.); visible 12 to 14 miles.

The outer extremity of the reef projecting from cape Jervis, lies 1600 feet to the S.W. of the lighthouse. (1871). Page 685.

* Early in 1874 a revolving white light will be exhibited from Port Adelaide pile light- house, in lieu of the present fixed light.

On January 1st 1874, a fixed red light will be shown from Glenelg jetty in lieu of the present green light.

And, a fixed green light will be exhibited from the semaphore jetty in org of the red light now shown.

ADDENDA. Ixi.

PORT WAKEFIELD (Gulf of St. Vincent). - The following instructions for making this port were issued at Adelaide, in September 1866 : -

From port Adelaide outer bar, steer N.W. by W. 4 W., making allowance for tide and leeway. The tides N.W.-ward of the lighthouse are strong; the flood sets over the long spit N.W., andthe ebb S.E., attaining at springs a velocity ot 2 knots.

Keep the above course (N.W. by W. 3 W.) for 25 miles, to sight a large red buoy with a pyramidal top, surmounted by a triangular head; this buoy marks the western extremity ofthe long spit, extending 20 miles to the westward. from the low sandy shore to the northward, and in the vicinity of the Gawler river. The buoy is placed at the south-west and western extremity of the shoal in 19 feet at low water, ordinary springs, in lat. 34° 33' 40" S., long. 138° 7' 40" E., with the western summit of the Hummock range of hills at the head of the gulf, bearing N. 8° W., and mount Lofty, 8. 56° 30' E.

The coast line on the east side of the Gulf, in the vicinity of the long spit, is very low, and cannot be seen from the deck of a small vessel when outside the buoy, unless there be much refraction. The coast on the west side, to the west- ward of the long. spit, is bold, and in places cliffy.

At about 14 miles northward of the buoy there is a swatchway or channel, in which there are from 6 to 8 fathoms. f

It is probable the patch on which the buoy is placedis detached from the main shoal; but until this portion of St. Vincent gulf has been accurately surveyed, this cannot be determined.

To the eastward and N,E. of the buoy the water appears to shoal gradually towards the land, the before-mentioned channel, or swatchway probably intervening.

Caution. - In thick weather, or in the middle of a summer's day, when the sun is ahead, and objects much affected by refraction, the lead should be carefully attended to; by maintaining a depth of 5 fathoms, reduced to low water, the edge of the long spit may be avoided, and the buoy sighted.

Sailing Directions - Having brought the buoy to bear N.E., distant 2 miles, steer N.W. by N. 3.N. for 5 miles, until the western summit of the Hummocks is seen bearing North, when alter the course to North for 15 miles, until the land at the head of the gulf is distinguished, and a bold hillon the east side (inside Sandy point) observed; then alter the course to N.N.E., not going into less than 43 fathoms, until a large nun buoy is seen; steer then to keep the buoy to the eastward, at a distance of z cables; then alter the course to North.

The buoy is placed in 17 feet on the outer extremity of the shoal spit, stretch- ing out to the westward of Sandy point, on the Bald hill spit. Before nearing the buoy, sail should be reduced, and the ship got ready for anchoring.

The soundings southward of the buoy are shoal; this portion of the gulf being only navigable by barges and small craft of little draught of water.

Thistle Rock. - This rock has been removed by blasting, the debris of the rock being only 3 feet above the surface of the bottom. Its position was lat. 34° 19' 2" S., long. 138° 11' 80" £.: from it mount Lofty bore S. 40° E.; and the west summit of the Hummocks range N. 20° W.

It will be seen by the above that the rock was apparently close in shore. This is owing to the imperfect charts of this portion of the gulf, as the rock was fully 2 miles from the low coast line. It was, however, quite out of the track of

Ixii. ADDENDA.

large vessels, and could be always avoided by not coming under 3 fathoms at low water.*

Anchorage. - Having brought the largest store in the township of port Wake- field to bear N.N.E. 4 E., or the buoy S. ? E., and the mangrove bushes:on the Sandy point to between E.S.E. and S.E. by E. 3 E., anchor in 4 fathoms at low water.

There will be room to swing in this berth, but not space to beat out of it with- out going into 18 feet at low water.

Beating up the Gulf. - In making a passage from the lighthouse to port Wake- field against head winds, make the first board to the westward, and stand on that tack - say West, - for about 16 miles, taking care not to come under 8 fathoms, so as to avoid the shoal water on Orontes bank; then, going about, endeavour to work between the two shoals - viz., Orontes bank and the long spit, - but, in drawing to the northward, do not fail to sight the buoy on the latter danger, as it forms an excellent guide for enabling a commander of a ship to know when he is to the northward of Orontes bank.

Being off the buoy, and consequently northward of Orontes bank, the western coast may be safely approached, making long boards from 5 fathoms outside the long spit, on the east side, to within a mile of the western shore.

On nearing Sandy point, the red buoy on the Bald hill spit should be passed as previously directed, when short tacks must be made, taking care not to bring the buoy to bear to the southward of S. 3 E., and not standing to the westward into less than 33 fathoms, anchoring in the space before indicated.

Anchorage for small vessels. - Small vessels may stand towards the creek, observing that the water shoals very rapidly, from 3 fathoms in some places; but even should a vessel touch the ground no injury will arise, as the bottom is generally composed of sand and mud, and there is no sea.

Care, however, must be taken to keep a ship in such a position as to be clear of her anchor.

Land Wind. - When leaving port Wakefield, it is advisable not to start until morning, when the wind generally being easterly, an offing may be easily obtained without beating out.

Winds. - The winds during fine weather, in the summer, are generally as follows : - From sunrise to-about 8h. a.m. from E. to E.S.E.: in hot weather, the wind in the morning may be from N.K., gradually falling calm towards 8h. a.m,

The sea breeze generally sets in after an interval of a couple of hours light winds, or calm at about 11, and freshens towards 5 o'clock, gradually moderating till sunset, when it comes round to the 8.E.., and dies away towards night. The barometer falls rapidly with northerly winds both in the summer and winter seasons, and generally precedes a change of weather from the westward.

In summer the change often occurs suddenly from the southward, when it blows hard.

In the winter the strongest winds are from the westward.

Tides. - The tides at the head of the gulfare very irregular, and much affected by prevailing winds.

-

* The coasters. report other small rocks in the vicinity of the site of the Thistle rock ; but until the gulf is re-surveyed, no further information can be given,

ee aS eee eS eS ee ee. Oe - _ - " . .

5 _ - Ss

ADDENDA. Ixi.

_ With strong westerly winds the rise of tide is much augmented, whilst the fall is much diminished. It often occurs during westerly winds, at neaps, that a higher tide will be experienced than at the springs, with fine weather, and south or south-east winds. ;

With the latter the tides are at the lowest, and the rise at springs is much reduced.

In fine weather, with the ordinary land and sea breezes, the time of high water at F. and C. is 5 hours, and the rise about 9 feet.

At neaps, in fine weather, the rise and fallis almost imperceptible, the time of apparent high water being very irregular.

Remarks. - Produce is now sent from port Wakefield to the shipping in the roadstead by barges. 'The river entrance is very shallow, and has a flat of upwards of a mile in extent, uncovered at low water springs. At a rise of 6 or 7 feet above the low water spring level, the loaded barges can cross the bar. The question of either deepening the entrance of the river, or building a jetty across the flat, is now under the consideration of the Government.

The supply of fresh water at port Wakefield is limited, and difficult to procure. It is, therefore, recommended that a sufficient stock should be procured at port Adelaide, if the ships call there on their way up the gulf; or water can be obtained by arranging for the barges used at port Wakefield, but which generally belong to persons at port Adelaide, bringing up asupply. Page 687.

Bald Hill Beacons. - Two triangular beacons have been placed on Bald hill, the termination of the low wooded range rising above the mangrove swamp southward of the town of port Wakefield, as anchoring marks for large vessels.

The upper triangular beacon, about 50 feet above high water mark is painted white, and distant 322 yards E. 4 S. from the lower triangular beacon, which is painted red.

Channel Beacons. - The channel leading to the anchorage has been recently deepened, and beacons have been placed on its edges; the western side of the entrance is marked by a black beacon with a round top, and the eastern side by a red beacon having a lozenge-shaped head: a similar black beacon and a red beacon are placed inside. '

Anchoraye. - Large vessels approaching this anchorage should shorten sail off the Spit buoy, and-anchor in 4 fathoms low water, with Bald hill beacons in line; Sandy point, the end of the low mangrove swamp under Bald hill, S.E. by E. 3 E.; and the Spit buoy S. 2 E.

A fixed white light has been eiehionad at the Railway shed of port Wakefield, visible 4 miles, to guide small vessels navigating the creek, With the light bearing N.E. by E. 3 E., the entrance to the creek is between the beacons. Page 685.

PORT WILLUMGA (Gulf of St. Vincent). - A large red buoy has been placed outside the edge of the reef, extending to the westward of Snapper point, the

southern horn of the bay in which lies'port Willunga.

The buoy is of pyramidal shape, with a round top, and may be seen at a distance of 4 miles in clear weather. It is moored in 104 fathoms at low water, immediately beyond the edge of the reef, and affords an excellent guide for clear- ing the rocky and uneven ground lying to the S.S.W. of the reef.

Ixiv. ADDENDA.

In the event of any accident happening to the buoy, the reef may be cleared by keeping the inn close to the beach (to the northward of the jetty) twice its own breadth open to the northward of the end of the jetty. 'The buoy is placed inside this mark.

The moorings which were laid down in 1855 have been removed; ships will, therefore, have to depend on their own anchors. The holding ground is good anywhere outside the 4-fathom line off the jetty.

Anchorage. - The anchorage is exposed to all winds from N.W. to 8.W. round by west. At times a heavy sea rolls in, rendering ships at anchor very uneasy, and, unless well found in ground tackle, in an unsafe position ; it is, therefore, recommended, on the approach of a S.W. gale - which is indicated by a falling barometer, and the wind freshening from northward, with a cloudy sky - that shelter should be sought in Eastern cove, Kangaroo island, where a ship may anchor in perfect safety, according to draft of water, and remain until the wind shifts to the southward, when she will have a fair wind to return to port Willunga to complete her loading. (1866). Page 689.

PORT .VICTOR (Encounter Bay). - Commanders of vessels bound to port Victor, port Elliot, or the mouth of the river Murray, are hereby informed that a very heavy break has been seen about half a mile south-east of the Seal rock.

The break was observed from the Government schooner Flinders, when lying at port Victor during an unusually heavy swell after a hard south-west gale. The sea did not break oftener than every half hour; but with such violence and volume as would imperil any small or deeply-laden vessel.

Immediately on the south-west swell slightly subsiding, the break was no longer seen. Soundings were taken in the Flinders during a favourable opportunity, when from 15 to 17 fathoms were found on a sandy bottom in the vicinity where the breakers were seen; it is moreover probable that less water may exist ona small patch ; but it is evident, from the sea being only seen to break on very rare occasions after violent south-west gales, no shoal water exists, as the ocean swell, if at all heavy, generally breaks on the uneven bottom to the southward of the passage between Granite island and Seal rock, on which there are 5 fathoms.

Commanders of vessels bound for port Victor, in rounding Seal rock during south-west gales, or during the heavy swell that often succeeds a gale in the offing, should either keep close to the rock (outside), or give it a berth of at least a mile, until it bears W.N.W., when a course may be shaped for the anchorage.

At night, when Seal rock can easily be distinguished, it is abvisable to keep off the land until daybreak, with the remarkable conical peak of Rosetta head bearing North - thus avoiding the bight of the bay between that headland and the Murray mouth and the rocky patches between Rosetta harbour and Seal rock.

The soundings off Seal rock do not afford any guide within a reasonable distance of the land. (1867). Page 690.

CAPE JAFFA or BERNOUILLI. - A light is exhibited from a_ screw-pile lighthouse erected on the reef off cape Jaffa. It is a revolving white light, eclipsed every half-minute, elevated 100 feet above the sea, and visible 16 miles.

The lighthouse is built of iron. Position lat. 36° 55' S., long. 139° 36' E. Page 691.

GUICHEN BAY. - Captain Douglas (Adelaide) has pullished the following instructions for this bay ; -

ADDENDA. Ixy,

Guichen bay is formed by cape Lannes (or Dombey), in lat. 37° 9' 45" S., long. 139° 44' 15" E., on its southerii extreme, and Baudin's rocks and reefs N. by W. 44 miles from thence, at its northern extreme. From cape Lannes, a reef of rocks runs N.N.W. 14 miles: from Baudin's rocks, another reef stretches 14 miles in a S.E. direction. Cape Lannes may be known by an obelisk on its extremity, 40 feet in height, painted red and white in horizontal stripes, which being about 100 feet above the sea level, is visible 12 miles from the deck of a moderate-sized vessel in clear weather; the coast to the southward is composed of sandy hillocks lightly timbered. Breakers extend fully 2 miles off this part of the coast, and, from their treacherous nature, and the heavy ocean swell settling directly on them, should be most carefully avoided. Baudin's rocks form a group of islets, situated from cape Lannes, N. by W., 44 miles; they are visible about 7 miles.

The bay inside the reefs, off cape Lannes and the Baudin's rocks, is 8 miles deep, and lined by a clean sandy beach, the bottom quite clear, and of excellent holding ground, with gradual soundings from 5 fathoms in the stream of the reefs to the shore, with the exception of a few rocky points, near the township, which terminates a few fathoms from the beach.

A convenient jetty, with a tramway from the road to the end, is now com- pleted, having, at its extremity, 6 feet at low water; boats can load here in any weather, by having a line fast to a grapnell outside, to steady them and haul off by.

Vessels bound into this anchorage, from the southward, should bring the obelisk on cape Lannes, to bear S.E. 24 miles, when the point of the reef will bear E.S.E.; having a leading wind, run in East until the obelisk bears S.S.W., and from thence steer South for the anchorage. Small vessels will find excellent anchorage inside the buoys, with the pier-head S.W. by 8. 3 8., and the obelisk W.4N.,in 8 fathoms, veering away a good scope of chain at once; and, in the event of bad weather, having a second anchor ready to let go.

Vessels coming from the northward should carefully avoid the reef off cape Jaffa, in lat. 86° 55' 30" S., long. 139° 35' 30" E., by keeping at least 10 miles off the point ; for, though the outer rock is not more than 5 miles from the beach, the bottom is so uneven that the sea often breaks in deep water, in bad weather, with such violence as would jeopardize a small deep-loaded vessel.

Having sighted the obelisk, and brought it to bear S.E. 6 miles, and the Baudin's rocks E. 2} miles, steer in S.E. by E.. keeping the reef off Baudin's rocks on the port hand or to the eastward, until the obelisk bears 8.W. by S. 3 8S. when shorten sail and stand in to the anchorage.

Small vessels in the winter season should carefully avoid anchoring too close to a rocky point at the eastern end of the town; as, in the event of their wanting to veer away cable, such a position might be inconvenient.

Vessels working into the bay with head winds will find the channel between Baudin's and cape Lannes reefs fully 24 miles broad; by not borrowing within the already prescribed distances, and keeping the lead going, they may work in safety, taking care not to approach the shelf, which lies inside cape Lannes, too closely. .

The barometer in this bay, as is generally found on all parts of the coast, is an invaluable guide. 'The mercury falling with a N.E. wind and sultry close

e

lxyi. ADDENDA.

weather in the winter season, is a sure precursor of bad weather, for which pre- paration should be made. Page 691.

MACDONNELL BAy. - Vessels bound into port MacDonnell by day should give cape Northumberland a good offing, taking care not to bring the cape to bear to the westward of N.W. by N., until mount Schanck bears N. by W., when a course may be shaped for the anchorage, which will then bear N.W.; stand boldly on, carefully observing the breakers on the reef. On this course, the water wili shoal rapidly from 10 to 6 fathoms, and as the beach is approached to 3 fathoms on a rocky bottom, generally, in the latter depth, the soundings will be very regular, as, although the ground is rocky, the patches appear to be composed of limestone flats covered slightly with seaweed.

Before thus closely approaching the coast, strangers should hoist the signal for a pilot, who will, if the weather be not too bad, come off.

Should the pilot not be able to board, it is recommended to obtain an offing until the weather moderates.

At night, except under the charge of the pilot, it is not prudent to enter the bay ; and masters of vessels should keep the light bearing from N.N.W. to N.N.E., taking care not to come under 25 fathoms water, which will place a ship about 5 or 6 miles from the cape. Masters of vessels acquainted with this port will find no difficulty in entering it by observing the following directions : -

On approaching from seaward keep point Douglas, a headland to the W.N.W. of cape Northumberland, well open of the latter, and mount Gambier more than the length of mount Schanck open to the eastward of the latter before standing in, after which steer for mount Schanck until the mooring-buoys are made out. By keeping the eastern set, bearing between N.W. 2 W. and W.N.W., they may be safely approached, when the Harbour-Master will, if possible, come off and moor the ship. ;

Masters of vessels are requested to carefully observe if any of the signals hereinafter mentioned are made from the flagstaff near the jetty.

In the event of the moorings being occupied, vessels entering the bay must anchor; and should be kept in such a condition, as to ballast and trim, as wil enable them to seek an offing in the event of bad weather coming on.

Although the moorings now laid down at this port are of the heaviest descrip- tion, and fully competent to hold any vessel that can enter port MacDonnell, it must be remembered that, during heavy south-west gales the sea rolls in over the outlying reefs, and breaks in the bay very heavily. On these occasions vessels will ride very uneasily, and be cut off from communication with the shore.

A life-boat and an efficient boat's crew, together with Dennett's rocket appara- tus for saving life, has been established at this port.

The following signals are established at this port. The flagstaff at which the signals will be displayed is situated near the base of the jetty.

ek

ADDENDA, ~ - Ixvil.

From Shipping to Signal Station on Shore.

Signals. When shown. By day. By night. Harbour Master ............ At Peak. Union Jack. { Waves: Bad ale ead red BERL OG errs tae cee ieti «cis. csreheis ethos At Fore. =f Two fiash or blue lights.

In harbour. - Two lights

horizontal at peak, In POMOC B Oia 5s sie 5's cal sieve « ofeie S At Peak. wee the Roads. - Two lights : horizontal. - one flash light. Shipping Master ............ At Fore. No. 1 Pennant. - WY PREM GERTLEC S. ass cca aie a sueia siayele's At Main. No. 6. - _ - Custom House Officer........ is Ensign. : - S Two blue or flash lights; Health Officer ...........66. : No. 9. { ire vention) Hgts ; Medical assistance required. . At Peak. No. 1. { ae Bear A thie two PLOVIGLONIAS tie cia cesta cise os At Main. No. 7. - MAIDA REOMG svete crite sews ss At Peak. No. 3. - P : Guns; blue or flash light, or LVESTBOAS Late oo ears aisioiaia Sete els oes _ Ensign Union rockets alternately, until down y ¥ reply is made.

Ship calling for orders ...... At Main. | Telegraph fiag. a

By day will be answered from shore by Numeral Pennant, by night by flash light.

From Signal Station on shore to Shipping.

Signals. Where shown. By day. By night. A Below Ensign : : Gale approaching from north pe a No. 1. Two horizontal lights. Ditto, north-west ............ q No. 8. | an Poet lights; one MDTDL Os IVORL ts dnl cleisle'e na mls g Oe " No. 5. Two vertical lights. Ditto, south-west ............ : No. 6. | Aye PV Pliiigheaas aS NEES BOUL 55:2 5,0'c lao eltine oe ste 9 No. 7. One rocket. : Ditto, south-east ............ a iy ona hia Sa gin lights; one | Send down top-gal, masts ; One flash or blue light; one and yards and let go second Above Ensign. No.6, rocket. ANCHO, Hai. ae osc igater ee ay . Proceed to sea. Not safe to ue an ] , remain at anchorage .... } a {white flag. | Wo rockets or two guns.

Anchorage unsafe............ _ Blue flag. One gun; one flash light

(repeated if necessary).

wicrorta. - New Flag. - A new Victorian flag, which, at the suggestion of the Admiralty, has been designed as the distinguishing mark of the Victorian Mercantile Navy, has been formally adopted by the Government. The ensign will have five white stars on the blue ground, and the "jack" five white stars in the cross of St. George, which forms the central line of the pattern. Pages 694 - 710.

PORT FAIRY. - A green light is established on the end of the jetty at port Fairy ; the light is cut to clear the buoy off the foul ground to the northward of the lighthouse, and visible, between the bearings of W.S.W. and S., about 3

niles. 7 Vessels entering port Fairy should steer in until the green light on the jetty is

Ixviil. ADDENDA.

opened out, when steer for it and anchor. The best anchorage is in about 3 fathoms, at about a cable N.W. of the black buoy off the foul ground, with the light on Rabbit island bearing S.S.E. (1872). Page 695.

KING ISLAND (Bass Strait). - A rocky ledge, which appears to be several miles in length in a north and south direction, has lately been found to exist 6 miles seaward of Sea Elephant bay, King island; the general depths on this ledge are 4} and 5 fathoms, but a patch with only 22 feet was found near the northern extreme, from which Sea Elephant rock bore E. 3 S., distant 44 miles.

As a dangerous sea will be found on this ledge during bad weather, ships should approach Sea Elephant bay with caution. Page 66.

WARRNAMEOCOL HAREOUR. - The following alterations have been made in the lights in Warrnambool harbour, Lady bay : -

The light on Middle island is discontinued and the lighthouse removed.

Leading lights are now established on the sites of the obelisks, on the hill ridges immediately in the front of town of Warrnambool.

The upper light, fiwed white, is shown over an are of 135° (from West south- ward to S.E.); it is elevated 109 feet above the sea, and visible 14 miles.

The lower light, fived red, is only shown over an arc of 123° (from 8S. + W. to S. by E.) ; it is elevated 87 feet above the sea, and visible 5 miles.

A fixed green light is exhibited from the extremity of Warrnambool jetty, the latter extends 230 yards from the shore.

Directions - Vessels entering Warrnambool harbour from westward or south- ward, should first sight the red light, (carefully avoiding the 17-foot patch which lies §.S.E. half a mile from Middle island), and then bringing it in line with the white light, bearing North, steer in between the 5-fathom bank and the foul ground south-east of the Breakwater rock until the green light on the jetty is opened, when steer in for it and anchor. From the eastward, either bring the marks above described on, or cross the bar to the south-eastward, taking care not to shut the white light in when standing towards the mouth of Hopkins river.

It is not safe to enter or leave the harbour in south-westerly or southerly gales. In bad weather, or with a heavy southerly swell, the sea breaks at the distance of a mile from the land. Variation 63° H. (1871). Pages 695-696.

BASS STRAIT. - Navigating Lieut. H. J. Stanley, R.N., reports that a reef on which the sea breaks heavily has been discovered in Seal bay, at the southern end of King island, lying from a mile to 14 miles east of Seal rocks. The reef ig apparently several cables in extent, with 6 fathoms on its north-west edge. Page 697.

PORT WESTERN. - A light is exhibited from a lamp-post on the outer end of Flinders jetty (a small jetty north of West head); it is a fixed light, white and red on different bearings, elevated 24 feet above high water, and visible 4 miles.

Vessels anchoring off the jetty should, to avoid fouling the submarine cable, anchor within the red light. Page 699.

PORT PHILLIP. - The lighthouse on point Lonsdale is coloured in red and white bands; it exhibits a fiwed light, visible about 10 miles. The light is green, from about S. by E. eastward to $.E. 4 E. (894°) ; red from 8.E. } E. eastward to

ADDENDA. 1xix.

E. by N. (503°); bearings from the lighthouse. Lonsdale point is a mortar and rocket station. Tidal signals, denoting the quarter of the tide with reference to the stream, are made at the flagstaff on the point,

The Lonsdale rock lies nearly 3 mile, and the Lightning rock 1,1, miles from the lighthouse, both on a 8.E. 4 E. bearing. While the green lights is in sight, vessels are outside these rocks; while the red light, inside : - the blending of the lights is on a line with the dangeas, hence the greatest caution is required when the colours are about to blend. Pages 697 and 700.

Shortland Bluff. - The Low lighthouse shows a fixed light at 90 feet above the sea, visible 10 to 14 miles. The light is white from S.W. by W. southward to S.W. (114°); red from S.W. southward to S.S.W. (224°) ; white from S.S.W. eastward to E. by S. (1014°) ; - bearings from the lighthouse.

The High lighthouse, a stone tower on the bluff at 352 yards N.E. by N. from the Low light, shows a fixed light at 130 feet above the sea, visible 17 miles. Its geographical position is lat. 38° 16' 27" S., long. 144° 39' 46" E. The light is shown seaward from about W. by S. to South (782°). By an observer close in with the Lonsdale land it will be seen only between the bearings from it of S.W. by W. southward to South (564°). Within the harbour it is shown over an arc of 180° (from 8.W. by W. southward and eastward to N.E. by E.) Short- land bluff is a Life-boat station.

The two lights in one, N.K. by N., lead in. The red light (in the Low light- house) must be kept in sight until within the Heads; the change of colour from red to white indicates the immediate vicinity of the reefs extending from points Lonsdale and Nepean, hence the line of the lights in one should be strictly followed. At the extremity of the reef extending from point Nepean (east side of the entrance) is the Corsair, a rock 8 feet under water, having a depth of the & to 5 fathoms close to it; Lonsdale reef is also very steep.* Pages 697 and 701.

Portarlington. - A green light, visible from W. by 8.48. southward to 8.E. by E. 3 E., is exhibited on Portarlington jetty, elevated 22 feet above high water, and visible 5 miles.

The light in sight clears the north side of Prince George bank to the east, and the buoy of point Richards to the west.

Schnapper Point. - A /ixed white light has been established on Schnapper point; it is elevated 50 feet above high water, and visible 10 miles.

The light at the end of the jetty has been replaced by a red light shown from an ordinary lantern, visible 3 miles. Page 700.

BANES STRAIT. - Navigating Lieut. H. J. Stanley, R.N., states that heavy breakers have been reported on the following bearings : - Mount William S.W. 3 W.; - Swan island lighthouse, W.N.W. ; - St. George's rock, S. 4 W.; and recently the ship, Salamander, struck and was severely damaged on a rock not far from the above neighbourhood. This rock was reported by the master of the Salamander to lie E. by S., distant 12 miles from Swan island lighthouse.

The Colonial governments of Victoria and Tasmania are about to have the dangers in this locality examined. Variation 10° H. (1869). Page 708.

* It is intended to establish two leading lights for South channel. The inner or eastern one (green) is now lighted, and is shown from the end of the jetty at Dromana, visible 4 miles.

Ixx. ADDENDA.

HALLY BAYLEY ROCK. - The master of the schooner, Hally Bayley, has reported the existence of a sunken rock having about 3 fathoms water on it, about 13 miles off the west coast of Tasmania, between cape Grim and West

point, on the following bearings: - cape Grim N.E. 4 E. 15 miles, and West point S.E. by E. 4 E.14 miles. These bearings place the rock in Lat. 40° 48'

30" S., Long. 144° 23' E. In bad weather the sea breaks heavily over the rock. Variation 9° EH. (1872.) Page 708.

PORT ALBERT. - The red fixed and flashing light at port Albert has been altered to a white fixed and flashing light, showing a flash every three minutes, yisible 11 miles. The fixed light shows for one minute forty seconds, it is then eclipsed for twelve seconds, and after the flash again eclipsed for thirty-four seconds.

Within a distance of 8 miles the light appears as a continuous fixed light between the flashes. Page 709. |

GABO ISLAND LIGHT (Cape Howe). - The western limit of Gabo Island light has been altered from 8.S.W. to S.W. by S. (from seaward), so as to clear the cape (cape Howe) and dangers to the southward. Variation 10° #. i 1872. Page 710.

KALI MAAS SHoOAL. - Captain Spring, of the Kali Maas, reports that in April 1869, being in Lat. 34° 9' S., Long. 58° 213' E., he had a good observation of a bank of white coral, with here and there dark stripes, apparently 30 feet long and 12 feet below the water, but in the trough of the sea not more than 5 feet below it. Page 716.

CORAL REEF. - The Marshal Pelissier reports that when running before a strong S.W.-ly wind, she struck on a coral reef in lat. 6° 503' N., about 8 miles off shore, the easternmost point of Ceylon bearing N.W. 3 N.

Rovurres ror STEAMERS FROM ADEN TO Sctnpa Srrair anp Back.

The following remarks are a synopsis of a pamphlet issued by the Royal Meteorological Institute of the Netherlands; by pursuing the routes indicated it will be possible "to make every voyage from Aden to Sunda, and back, with wind and current, except during the months from November to March, when it will be necessary to steam up with a head wind under the coast of Sumatra (from the Strait of Sunda) till the equator be crossed."

1. April, May, and June. - Aden to Sunda Strait - During the first half of April the winds are variable in the Arabian gulf: in the latter half of April vessels on leaving the gulf of Aden meet the 8.W. monsoon, which blows with considerable force throughout May and June: this admits of a straight course for Sunda strait, between the Maldive and Laccadive islands, - going south of Mini- coy: at the end of the run make Engano, and thence lay the course between Eingano and the coast of Sumatra for the Flat Point of Sumatra.

Sunda Strait io Aden. - Vhe S.E. trade wind being prevalent between Lat. 5° and 10° S., run on the parallel of 8° or 9° S., and thus south of the Chagos archipelago; then come up slowly towards the equator so as to croas it about the meridian of 60° F.; full advantage is thus taken of the southerly and S.W.-ly

ADDENDA. Ixxi.

winds, which will at first be light, but steadily increase in strength as the ship makes progress, so that she reaches the gulf of Aden between Socotra and cape Guardafui.

2. July and August. - Aden to Sunda Strait - - The S.W. monsoon is still pre-

valent and strong, therefore the route is on the whole the same as that for April to June.

Sunda Strait to Aden. - The §.K. trade wind now extends nearly to the

equator, therefore take a course northward of the Chagos archipelago, till the

S.W. monsoon is met with, then shape a course for the gulf of Aden between

Socotra and cape Guardafui.

8. September and October. - Aden to Sunda Strait. - Take a more northern route, in order to make the most of the westerly winds which are increasing in force there: the track runs north of Minicoy, and it is best to cross the equator eastward of Long. 95° E.: according to the weather, run inside or outside the Mantawi islands, and then into Sunda strait along the coast of Sumatra.

Sunda Strait to Aden. - The 8.E. trade wind being on its way back, the route southward of the Chagos archipelago should be chosen, as in April to June.

4. November, December, January, and February. - Aden to Sunda Strait. - The N.E. monsoon is now prevalent in the northern part of the Indian Ocean, and from the meridian of Mauritius to Sumatra the calm belt has moved south- wards, towards the equator : shape a course between Socotra and cape Guardafui, to seek the calm belt, then steer between the Maldives and the Chagos archipe- lago, towards Engano.

Sunda Strait to Aden - To reach the N.E. monsoon, lay along the coast of Sumatra, where, when steaming against wind and sea, the force will be the least possible: this may be westward or eastward of the Mantawi islands: when north of the equator and in the N.E. monsoon, shape a course for Aden to the south of Ceylon and north of Minicoy.

5. March. - Aden to Sunda Strait - The force of the N.E. monsoon is failing, and N.N.W. winds appear: go southward between Socotra and cape Guardafui ; cross the equator between 68° and 72° E.; lay the course for Sumatra in the calm belt of variable westerly winds, taking care to cross the meridian of 100° E. northward of the parallel of 5° S.

Sunda Strait to Aden - As from November to February, steam N.W.-ward along the coast of Sumatra, westward of the Mantawi islands: when up to the parallel of 4° or 5° N., with the variable easterly winds a course can be set along Ceylon, thence through the Nine Degree channel, and to the north of Socotra for the gulf of Aden.

The Currents are entirely dependent on the winds even when these have only blown for a few days from the same point. Pages 731-748.

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PART I.

NOTES

ON THE

PHYSICAL GEOGRAPHY

OF THE

INDIAN OCEAN

IN ITS APPLICATION TO NAVIGATION,

CHAPTER I. INTREODUOTO Ry:

1. THE INDIAN OCEAN, like the Atlantic and Pacific, has its boundaries partly natural and partly artificial: it is limited westward by the African and Arabian coasts; and northward by Persia and India - the latter (by its peninsular-form) break- ing it into two deep and nearly symmetrical indentations; its eastern boundaries are Birmah, the Malayan peninsula, the west coast of Sumatra, the southern coasts of Java, Baly, Lombok, Sumbawa, Floris and Timor, and the west coast of Australia from Melville Island on the north thence round to the southern point of Tasmania; these constitute its natural lines of demarcation: southward it communicates freely with the Great Southern Ocean, but its artificial boundaries in this direction are the meridian of Cape Agulhas on the west, and that of the south point of Tasmania on the east, each prolonged to the Antarctic Circle, which forms its southern limit,* - ~ and hence the track of vessels bound for the colonies of Australia and New Zealand lies in the Southern Indian Ocean.

Within the boundaries just indicated the Indian Ocean cannot be said to be rich in islands: in mid-ocean, rocks, shoals, and vigias - some real and some imaginary, such as have been and still are so frequently reported as existing in the Atlantic and Pacific - are comparatively few, although such dangers are numerous enough in the

* Those are the b ipcep oe 'al boundaries of the Indian Ocean as settled by the Council of the Royal Geographical Society in 1847, B

2 INDIAN OCEAN.

vicinity of some parts of the coast. The continental islands are represented by Madagascar and Ceylon; the oceanic islands - sometimes volcanic, sometimes of coral formation, sometimes partaking of both characters - dispersed singly or in groups, have representatives in Mauritius, Réunion, the Seychelles, Kerguelen, &c. &e., and in that long chain which, commencing with the northernmost of the Laccadives, is continued through the Maldeeves to the Chagos; but by far the most remarkable mass of islands - one which has nowhere else a parallel - is the Indian Archipelago, which, while sketching out the connexion between the Asiatic and Australian con- tinents, forms, by the numerous channels and straits between the islands, the ouly equatorial communication of the Indian with the Pacific Ocean, - the channels, how- ever, being everywhere encumbered with a wilderness of shoals and rocks, islets, and small islands, rendering the navigation of that region the most hazardous on the globe.

The chief branches of the Indian Ocean are the Bay of Bunaat, the ARABIAN Sea, the Rep Sea, the Prrstan Gulf, the Mozamprqur Channel, and the Straits of MALAccaA.

The fame of the isles which stud the Ocean as its waters roll by their shores from the Pacific to the Indian had, in early ages, filled the minds of western adventurers with luxurious dreams of gold, pearls, gums, spices, rubies, sapphires, emeralds, velvets, damasks, silks, and the " purple light of perfumed lamps." From such visions, created by the romancing of earlier voyagers, men awoke to soberer views of the barbaric grandeur of the people and of the neglected treasures of those distant groups - for there was wealth enough and to spare. Extending through thirty degrees of latitude and forty-five degrees of longitude, the Archipelago is the centre of those ocean highways which connect the Asiatic nations with the ports of Europe and Western America. It lies along both sides of the equator, and is approached from the west through the Straits of Sunda and Malacca, - with openings from the southward too numerous to indicate here. The islands are abundantly volcanic, and the islets, rocks, and shoals are of coral : their appearance to the navigator of the narrow seas that separate them is singularly pleasing - while the dangers for incautious mariners are strewed about by myriads; but it is in this very region that commercial enterprise has yet to show its power in the development of unbounded wealth at present neglected.

It is the whole of the oceanic area here briefly indicated - the coast-line sur- rounding it, and the groups of islands scattered over its surface - the bays, gulfs, and straits - the principal ports, harbours, and roadsteads - the character of the seasons, and of the prevalent winds - the tides and currents - together with other information aseful to the Navigator, which will be found abundantly discussed and examined in the following pages, and in such a form that the work may be a complete

"SAILING DIRECTORY FOR THE INDIAN OCEAN,"

THEORY OF THE WINDS. 3

CHAPTER II, GENERAL REMARKS ON THE WINDS AND SEASONS.

2. The WINDS representative OF THE DIFFERENT REGIONS OF THE GLOBS. - In parts of the world widely separated there is a distribution of the winds peculiar to the region, and these differences serve to characterize the climate of each. In and near the tropics,in the Atlantic and Pacific Oceans, the winds blow, almost all the year, from the same points of the horizon - the eastern - the deviation being near the equatorial regions, where the " belt of calms" separates the ' N.H.-ly peren- nial Trade-wind" of the Northern Hemisphere from the "S.H.-ly Trade-wind" of the Southern Hemisphere. In the Indian Ocean (and in the seas conrlected with it) the same persistency of the winds during the whole year is not observable between the tropics; here they ave periodical, blowing for five months from one quarter of the horizon, and for another five months from an opposite quarter; these are the ** Monsoons ;" and the interval between the termination of one characteristic wind and the setting-in of another is known as the " change" of the Monsoon. In middle and higher latitudes all the winds are variable, but with a general prevalence from the west, being 5.W.-ly in the Northern Hemisphere, and N.W.-ly in the Southern Hemisphere. On the sea-coast - more or less in all climates, but especially between the tropics - a regular period of change is observed every day; at nearly the same hour in the evening the wind blows from the land, in the morning it comes from the sea; these are the " land-and-sea breezes."

In this brief sketch is indicated the general distribution of the different currents of air over the surface of the globe, while the alternating land-and-sea breezes give us an insight into their origin. |

3. THEORY OF THE WINDS. - The main cause of the disturbance of the equilibrium of the atmosphere and of the propagation of currents of air (winds) over the surface of the globe is the wnegual heating of portions of that surface more or less widely separated ; for, under the influence of heat, the air expands and becomes lighter, and even acquires an ascensional (or upward) tendency when pressed upon by the cooler (and heavier) particles surrounding it. We see the simplest instance of this in the land-and-sea breezes prevalent on nearly all seaboards at certain seasons, and especially characteristic of all large tropical islands. The respective surfaces of land and water absorb and radiate the sun's heat unequally, and the variation in the atmospheric temperature corresponds thereto: in proportion as the sun rises above the horizon, the land becomes warmer than the neighbouring ocean, hence the cooler sea-breeze sets in towards the land to restore the equilibrium. During the night, the process is reversed, the land loses heat by radiation and cools more quickly than the ocean, hence the stream of air flows from the land towards the sea as a land- breeze, which ceases as soon as the density of the two atmospheres has again become the same. gh

Similar causes on a large scale set the whole atmosphere in motion - producing winds characteristic of the tropical regions on the one hand, and of the temperate and polar regions on the other,~-the direction and intensity of each system of air-

currents being, however, greatly modified (1) by the earth's rotatory motion, and B2

4 THEORY OF THE WINDS.

(2) by the relative position of the continents and the oceans. Such was the theory first announced by Halley,* and afterwards enlarged and medified by Hadley,t - the latter insisting especially on the necessity for the S.W. and N.W. compensating currents beyond the tropics.

The effect of the diurnal motion of the earth in altering the direction of a current of air moving from North to South, or vice versd, will be readily understood; for, since all circles parallel with the equator decrease in circumference as they approach the poles, it follows that, in one diurnal revolution, a spot on the equator must describe a greater circle than any spot in middle and polar latitudes, and must con- sequently move with greater velocity: the earth in turning on its axis from west to east carries the atmosphere with it and imparts its own motion to it; a polar current of air, therefore, on passing towards the equator takes with it only the velocity which it had acquired from that part of the earth whence it came, and must, in its progression, be moving more slowly than the region towards which it is travelling ; in being thus left behind, the apparent motion will be in the contrary direction, and, accordingly, the North wind in the Worthern Hemisphere and the South wind in the Southern Hemi- sphere - the tendency of both being ever towards the equator - will have a westerly direction impressed upon them by virtue of the movement of the earth on its axis, 7.e. the North wind will become successively a N.E. and East wind, - and the South wind, a S.E. and East wind, for their respective hemispheres; and these are the TRADE-WINDsS- - perennial (or constant) breezes - the expression at once of the differ- ence of temperature between the tropics and the polar regions, and of the permanent inequality of the distribution of thesolar heat: but the Monsoons - so character- istic of the tropical area of the Indian ocean - being periodical winds, are expres- sive of the difference of temperature between the extreme seasons of the coun- _ tries where they are prevalent, as will be presently shown in detail.

Where the trade-winds approach towards each other, and from the excessive heat of the equatorial regions take the form of an ascending current, is the Region of Equatorial Calms, or Doldrums - an irregular belt varying in breadth and form, as well as oscillating with the sun's position in the ecliptic. Notwithstanding, however, that the predominating condition of the air within this belt is one of intense (oppressive) heat and general stillness, the equilibrium is but imperfect, and consequently easily disturbed ; - storms occur occasionally, and are frequent in the vicinity of the land, - while deluges of rain at intervals of a few hours are accompanied by deafening thun- der and the most vivid of forked and sheet lightning; here also originate the hurricane and cyclone.

The upper or return Trade-winds (' CountER-TRADE" of Maury, and Anvtt- TRADE" of HerscHEL) are the natural consequences of the ascending current of air at the equator overflowing and passing off towards the temperate and polar regions ; in the Northern Hemisphere the heated air is determined towards the north, - in the Southern Hemisphere, towards the south, and hence these equatorial air- eurrents must behave in a manner exactly the reverse of the polar: they come from regions moving with the greatest speed round the earth's axis - a speed which they share themselves - and as they advance into higher latitudes where the rate of Lot) SE RS Ge ec

* An Historical Account of the Trade-Winds and Monsoons observable in the Seas between

and near the Tropics, with an attempt to assign the Physical Cause of the said Winds. PHIL. TRANS, 1686,

+ The Cause of the General. Trade-Wind, Puiu, TRANS, 1725.

THEORY OF THE WINDS. 5

motion is slower, they must, the further they get from the place of their origin, appear to move to the east at a rate proportionate to the difference hetween their own velocity and that of the earth in the latitude at which they arrive ; - thus the wind is from the westerly points of the horizon, which combined with the initial movement (from N. or 8.) gives a S.W. wind for the temperate zone (or middle lati- tudes) of the Northern Hemisphere, and a N.W. wind for the middle latitudes of the Southern Hemisphere.

Where the equatorial upper currents first approach the earth's surface (in about lat. 30°) is another Calm-belt - in each hemisphere - chiefly remarkable however for light baflling airs, intermingled with frequent squalls; that of the Northern Hemisphere is known (after Maury) as the Calm-belt of Cancer or the Horse- latitudes - that of the Southern, as the Calm-belt of Capricorn; here the winds from S.W., N.W.,N.E., and 8.E. blow (approximately) the same number of days in the year, for within these belts a constant conflict is sustained between the upper (descending) and the surface currents of air - a portion only of the former current pursuing its course polar-wise, since a large part necessarily returns to the equatorial regions to feed the Trade-winds.

4. MAURW'S Theory of the circulation of the wind, in which the air is supposed to travel from pole to pole and then return to the place whence it originally started - making the Trade-wind of one hemisphere pass into the other hemisphere as an upper current within the tropics, and so also placing the source of the rainfall of one hemi- sphere in its opposite - is known to all navigators who have read either his " Sarnine Directions," or his " Paystcan GroGRAPHY oF THE SwA,' - works which dis- cuss the theory at great length; it is sufficient here to say that such a system of atmospheric circulation does not find acceptance with the best meteorologists - British and Foreign.

5. DOVE'S Theory - Tne Law or Gyration: - The general tendency of the wind to "veer with the sun " is an old observation,* but now confirmed; in fact, meteorological data, accumulated with assiduous care during the last 30 years, show that the wind often makes a complete circuit in that direction - passing (in northern latitudes) from south through west, north and east, to south, in succession - or some- times making more than one circuit in succession, occupying several days or weeks in such veering; and thatit rarely veers in a contrary direction - against the suin" - and rarer still makes a complete circuit in such a direction. The credit of having reduced these data into a system is due to Dove, of Berlin, one of the first meteorologists in Europe - who, by comparing observations gathered from all parts of the world, infers that the influence of the earth's rotation is not alone felt in the great system of

* Lord Bacon, in his " Historia Naturalis et Experimentalis de Ventis," speaking of the order of succession of the winds, says, - '' When the wind shifts in the direction of the sun's course - that is, from morn till noon, and from noon till evening, &c., it seldom retrogrades; or when it does so, it is only for a short time. When, however, it shifts in the opposite direction - that is to say, from morning till midnight, from midnight till evening, &¢. - it always returns to its initial point; at all events it does so before it has gone quite round the compass. When the south wind has blown for two or three days, the north will suddenly blow towards it; but when the north wind has blown just as many days in succession, it is not succeeded by the south wind until an easterly one has blown for some time." Still earlier observations to the same effect were made by ARISTOTLE and PLiny. The latest observers are MARIOTTE, in France; STURM, ROMME, KAEMTZ, and Dove, in Germany; and TOALpo, in Italy.

6 THEORY OF THE WINDS.

circulation which affects the whole atmosphere, but that even oca/ aérial movements are modified by it; this is the basis of what he terms the Law or Gyration* (or Rota- TION) of the Wind - a law not peculiar to any particular region, but, in fact, the general law (with few exceptions) throughout the world - and he has shown, that the Trade winds, and the entangled relations of the winds of the temperate zone, are but the necessary and simple results of the same physical conditions.

Suppose an observer stationed at a spot, in the NortHnrn HEMISPHERE, where the excitement of the wind begins - where, for instance, currents of warm air are mounting upwards from the heated soil, and if by this agency a current sets in from the North, he will see the wind-vane settle itself at first in a direction due North and South; if the cause of this motion of the air continues to act, the air of higher latitudes must share more and more in the effects, and coming to the place of obser- vation from a continually higher and higher latitude, it arrives with continually less and less rotatory velocity; hence, in its passage over the station, it will take a direc- tion more and more towards the westward, and thus the wind-vane must gradually pass from a North direction through N.EH. to Hast.

If the North wind has passed by degrees into an Hast wind, the air will assume the rotatory velocity of the place over which it is situated, and it will thus remain suspended over it in a state of relative rest. If the tendency of the air to rush towards the equator still continues, precisely the same phenomena as before indi- cated will be repeated.

__ If, however, a South wind spring up and impinge on the polar current, which has

become more or less easterly, it will evidently be deflected towards the North, and the wind pass through §.H. to South. As the northward movement continues, the South wind will shift gradually round through 8.W. to West, for the fresh arrivals of air * (coming from the equator towards the poles) move from places which possess a greater rotatory velocity towards those which move /ess swiftly eastward.

A West wind will have a neutralizing effect on equatorial currents, and reduce them to rest. If the tendency towards the pole continues, the phenomena will always be repeated, until fresh polar currents change the West wind (through N.W.) into North, finally coming round again to N.E.

Similarly, in the SoutTHERN HEeMIsPHERE, winds which at their outset are South will gradually pass through S.E. towards East. An equatorial current (from the North) impinging on the polar current, which has become more or less easterly, will cause it to veer from East, through N.E. into North; and the movement continuing, the northerly wind in its progress will shift more and more through N.W. to West.

The West wind, as is the case in the Northern Hemisphere, will tend to check equatorial currents, and reduce them to relative rest; but if the polar-ward tendency continue, the phenomenon will always be repeated until fresh polar currents change the West wind (through 8.W.) into South.

6. If, therefore (A), polar and equatorial currents are alternating with each other in the northern hemisphere,.the regular shifting of the wind round éhe compass will

be through s - §8.,5.W., W., N.W., N., N.E., E., S.E., 8. a

* "DAS GESETZ DER DREHUNG."- - -This Jaw is amply illustrated in the recent work of this meteorologist, "DAS GESETZ DER STURME in seiner Beziehung zu den allgemeinen Bewegungen der Atmosphire." (The Law of Storms considered in relation to the ordinary moyements of po Atmosphere.) 2nd. ed. 1861.

THEORY OF THE WINDS. 7

and the changes will take place oftener between South and West, and between North and Hast, than between West and North, or Hast and South; - for the first changes show a continuance of the exciting cause, while the latter point to a change of it - and being transition winds, they cannot blow for any length of time.

By alike course of reasoning (B), when, in the southern hemisphere, polar currents alternate with equatorial, the regular shifting of the wind round the compass will be successively through

s - §.,8.H., H., N.E., N., N.W., W., S.W., 5S. a>

and the changes ensue oftener between North and West, and between South and Hast than between West and South, or East and North.

7. This is the LAw oF GyratTion, - or the Law of the Rotation of the Wind - and we see that the veering of the vane may merely indicate the existence of a steady current of air. It is a misapprehension of this fact that causes the existing confusion with reference to questions bearing on the theory of the winds. The essential difference between the veering of the vane as produced by a steady breeze and that resulting from a centripetal current, or a whirling motion with an advancing centre, is, however, that in the first instance (¢.e. with a steady breeze) the rotation is constantly in the same direction, but in the case of the second it veers on both sides of the track and in opposite directions. If, therefore, as regards the Northern Hemi- sphere, the partial rotation through §., W., N., E. be called " with the sun" or direct, and the partial rotation through S., E., N., W. be called "against the sun," or retrograde, as is customary: and similarly, in the Southern Hemisphere, the partial rotation through §., E., N., W. be called " with the sun,'"* and the partial rotation through 8., W., N., E. be called " against the sun,'* it follows that -

Steady winds turn the vane only in a direct sense, or with the sun;

Whirlwinds, or centripetal gales, when they advance, turn the vane either with or against the sun, according to the side on which the vortex passes by the place of observation.

When steady winds from different directions approach each other, rotations com mence in either way ; - direct when, on the west side of the compass, a wind is more northerly than that which preceded it, and retrograde when it is more southerly. On the east side, on the contrary, the gyration is direct when 4 wind is more southerly than its predecessor, and retrograde when it is more northerly. Winds blowing from directly opposite points may, by arresting each other's course, produce a calm, and therefore give rise to the same pheno- menon which is visible in the vortex of a centripetal current (or in the centre of a whirlwind), that is to say, a calm intervening between opposite winds.

* Neither of these expressions accords with the seaman's view: he is accustomed to regard a movement from left to right as boing '' with the sun," for the term originated in the northern hemisphere, beyond the tropic, where the sun culminates in the South, and hence, looking in that direction, the sun rises on the left and sts on the right hand - i.e. left to right, '' with the sun ;" this idea, he carries over eyery part of the globe. But, in truth, left to right, "with the sun," is erroneous in the southern hemisphere, for, to an observer there, the sun culminates in the North, aud when he looks in that direction he sees the sun rise on the right hand and set on the left, hence for the southern hemisphere right to left is " with the sun." The northern term - left to right "" with the sun" - is therefore scientifically inaccurate when used in the southern hemisphere ; the expression in the text is consequently correct, but not in the seaman's sense.

.

8 THEORY OF THE WINDS.

And we thus see that the same phenomena may occur under totally different con- ditions.

8. Such is a brief sketch of Dovn's law of the rotation of the winds; and a general summary of the result of his investigations may be given in (nearly) his own words, as follow : - *

(1.) All steady winds are modified by the rotation of the earth in such a manner

that equatorial currents receive a westerly deflection, and polar currents an easterly deflection.

The N.E. and the S.E. Trade winds are steady polar currents.

The Monsoons are alternations of a polar and an equatorial current twice during the year, - therefore, they are N.E. and S.W. in the northern hemisphere, - and §.E. and N.W. in the southern hemisphere.

(2.) Bodies of air set in motion from a state of rest turn the wind-vane in the

direction of the meridian, as follows : -

(a) The polar current in the northern hemisphere, from N. to E.

(>) The polar current in the southern hemisphere, from 8. to E.

(c) The equatorial current in the northern hemisphere, from 8. to W.

(d) The equatorial current in the southern hemisphere, from N. to W. Hence, of the winds in the northern hemisphere -

(a) Those from N. to E. are the polar current. ;

(2) Those from E. to S. mark the transition of a polar to an equatorial

current.

(c) Those from S. to W. are the equatorial current.

(¢) Those from W. to N. mark the transition of an equatorial to a polar current.

Similarly, in the southern hemisphere, the winds -

(a) From S. to E. are the polar current.

(2) From E. to N, mark the transition of a polar to an equatorial

current.

(c) From N. to W. are the equatorial current.

(¢) From W. to S. mark the transition of the equatorial to the polar

current.

A complete rotation in the xorthern hemisphere is therefore -

wz §S., W.,N.,E.,S. 2 with the sun. And in the southern hemisphere - zw» §.,E.,N., W.,S ss also with the sun.

(3.) The course of a steady wind may be obstructed by the deflection originating in

the rotation of the earth : -

(a) By a wind blowing constantly in a direction perpendicular to its primitive one: such are the West India hurricanes, which, for this reason, go first from S.E. to N.W.; and those of the southern hemisphere, from N.E. to 8.W. f

(2) By an aérial current with less deflection ; such are the typhoons during the S.W. monsoon, which is circumscribed farther to the eastward by the South monsoon. Of the typhoons, however, many probably

* "Das Gesetz der Stiirme," p, 187 - 192.

THEORY OF THE WINDS. 9

have a progressive motion from W. to E., caused by the heavy air of the trade-wind region - situated to the eastward - rushing di- rectly towards the rarefied air of the region of the 8.W. monsoon, and thereby producing a whirlwind.

(c) By a mechanical impediment; asin the instance of a storm (described

by Prpp1neTon) which occurred in the Bay of Bengal, June, 1839.

In these cases, when the storm is an equatorial one, whirlwinds are produced in the

northern hemisphere in a direction contrary to that in which the hands of a watch

move: and in the sowtheri hemisphere in the same direction as the hands of a watch

move. Hence in the northern hemisphere the following shiftings of the wind-vane occur i=

(a) If the vortex (or centre) of the storm passes to the westward of the

place of observation - The rotation will be s - S.,W.,N.,E.,8. ss with the sun;

(4) If the vortex of the storm passes to the eastward -

The rotation willbe s - > S.,E.,N.,W.,S. s - against the sun. But, in the southern hemisphere, when the storm is also an equatorial one : - (a) If the vortex of the storm passes to the west of the place of ob- servation - The rotation willbe w - S.,E.,N.,W.,S. ss - > with the sun;

(2) If it passes to the eastward -

The rotation willbe # - > S.,W.,N.,E.,S. s> against the sun.

Thus, in both hemispheres, the passage of an EQquatoriat whirlwind-

storm on the west side of the place of observation produces normal revolutions, z.e. revolutions in accordance with the law of gyration ; but its passage on the east side produces anomalous revolutions, 2.e. contrary to the law of gyration. Potar whirlwind-storms move precisely in an opposite direction: - the revolution is normal when the vortex passes to the eastward, and anomalous (or abnormal) when it passes to the westward of the place of observation.

The old rule that "anomalous shiftings of the vane occur in stormy weather" is in this manner justified. It cannot, however, be ascertained from those shiftings whether an equatorial whirlwind passes on one side, or a polar one on the other ; - this depends on the initial point of the shifting, and, as a consequence of the whirlwind, can never amount to more than half a circle.

(4.) The vane may shift from one direction to that immediately opposite to it -

(a) When steady winds oppose each other, or fight with each other, as the

seaman says ;

(>) When the vortex of a whirlwind-storm passes over the place of

observation.

(5.) A whirlwind-storm may be passing even when the wind-vane does not shift at the place of observation. This happens when the place is but touched by the whirlwind. On one side the storm then appears to retrograde, - and on the other to advance : - for instance, a whirlwind (revolving in a direction contrary to that in which the hands of a watch move) is advancing from S.W. to N.E.; on the north-west side of such a storm, a N.E. wind appears

10

THEORY OF THE WINDS.

in the south-westerly regions earlier than in the north-easterly, whilst on the south-east side of the storm a S.W. wind actually appears to advance, i.e. it enters the north-easterly regions at a later period. The first, is the well-known case observed by Franklin during an eclipse of the moon. Those who, founding their theory on this and analogous instances, divide the winds into positive and negative, - into winds par inspiration, and par impulsion, - call one side of such a storm positive and the other negative.

(6.) In the temperate zones storms are caused, also, by two currents of air in

juxtaposition, - one pressing laterally on the other, - and during the transi- tion, the shifting of the vane may be either with or against the sun, but ever according to the direction of the currents impinging on each other.

(7.) Local phenomena (as land and sea breezes, winds blowing through valleys,

deflections of the trade-winds along the coast, trombs, &c.) affect the wind vane according to local conditions, and they may be such as either to produce a veering of the vane in accordance with that consequent on general air- currents, or one in an opposite direction. In open regions they are more prominent during the day, when the general air-currents are less prevalent ; - so also in the region of the " variables' between the trades, at the time the monsoons change, and particularly in summer, when the ascending current (courant ascendant) weakens the power of the horizontal currents. Indeed, it is not impossible that, setting aside local influences, one cause of a periodical shifting of the vane is to be found in the daily course of the sun ; - thus, if the spot where the daily maximum of temperature occurred formed a point of attraction for bodies of air lying near it, the direction of the wind during the morning would necessarily be westerly, and during the afternoon easterly, - and thus the vane would turn in a direction contrary to the movement of the magnetic needle.

As whirlwinds are not confined to a definite locality, the probability that any given place is situated on its east side is just as great as that it should be on the west side; the same remarks also apply where whirlwinds owe their origin to local causes- - and thus display a great degree of similitude as regards their course. The predominance of the gyration of the wind in a certain direction (with the sun) is consequently a phenomenon which is not connected with the whirling motion of the storm-winds, but only with the influence of the earth's rotation on progressive steady winds.

Now three things are possible : -

1, Hither all revolutions of the vane through great arcs are caused by whirl-

winds; and in this case, -

(a) If these whirlwinds occur first at one spot and then at another, indifferently, then there is no predominating direction in the shifting of the vane;

(6) Or, if the origin of these whirlwinds is local, and if in their progress they advance more or less along the same path, then there are, at certain places in each hemisphere, predominant shiftings of the wind-vane in the direction S., E., N., W., and in others, in the direction S., W., N., E.

THEORY OF THE WINDS. | 1

2. Or, all shiftings of the wind-vane commence with the alternation of steady meridional air-currents, in accordance with the principles of Hadley's theory of the trade winds, and in consequence of opposing currents pushing through each other: then the vane traverses in the direction S., E., N., W. in the northern hemisphere, - and 8., W., N., E. in the southern: 7.e. in both cases the wind veers with the sun. The backing of the wind cannot under these conditions exceed the quadrant of a circle.

3. Or, lastly, the shiftings of the wind-vane arise, in both ways, (1) from the alter- nation and displacement of meridional air-currents, and (2) from a progressive whirlwind; consequently, in each hemisphere, both descriptions of rotation must occur, but that " with the sun" will predominate. The first cause - alternations of meridional currents - produces (in both hemispheres) only

_ gyrations with the sun; and the second - d.e. the whirlwind - just as many with the sun as against it. Hence, however frequent whirlwinds may be, there must always be more gyrations that are direct than retrograde.

It is well known that whirlwind-storms, hurricanes, or cyclones, originate at certain places, and spread in certain directions; for instance, -

(a) The West India hurricanes (Aracan or Huiran-vucan of the coast of Mexico, Vuthan of Patagonia) commence on the inner edge of the N.H., trade, and even within the trade itself, especially in the latter part of summer and in autumn, the whirling motion of which is caused originally by the wind blowing from the S.H. encountering the N.E. trade, or by portions of the upper trade descending from above. They progress from 8.E. to N.W. in the torrid zone, then recurving at right angles at the outer edge of. the trade-winds, they move from §.W. to N.E.; during the progression the whirlwind, which revolves in a direction opposite to that in which the hands of a watch move, expands very considerably. In the region of the S.E. trade-wind of the Atlantic, whirlwind-storms occur with less frequency.

(2) The typhoons in the northern Indian Ocean and China Sea occur most frequently in autumn, but are also violent at the commencement of the S.W. monsoon. 'The direction in which they advance is rather more from E. to W. than from N.H, to 8.W., especially on the south coast of China. In the southern half of the Indian Ocean they are likewise very violent, going there from N.E. to 8.W., and recurving at right angles at the outer edge of the trade, whence they advance from N.W. to 8.E.

The rotation of the air in the whirlwind-storms of the northern hemisphere is in the opposite direction to that in which the hands of a watch move; and in the direction with watchhands in the southern. The causes which produce these effects lie in the lateral juxtaposition of the regions of the monsoons and trade winds, as well as in the displacement of one monsoon by the other.

Under certain local conditions, a whirlwind-storm may be so modified as to assume at particular spots the form of a steady wind; although, when its course is observed over a large circuit, it shows itself to be a real whirlwind. This is the case, for instance, according to RepFreLp, with the hurricanes (northers) of the

12 TRADE-WIND REGION - ATLANTIC.

northern part of the Gulf of Mexico, which, especially from September to March, at Vera Cruz, reach their greatest height four hours after they commence, and then rage for 48 hours with undiminished fury. The explanation given by REpFIELD of this long duration of the storm without changing its direction is, that the whirlwind advancing from the eastward comes in contact with and is arrested by the high land, by which means it becomes, as it were, flattened, and its circular form is partially changed to a rectilinear one. The N.E. and N.N.K. storms in the Pacific Ocean, on the coasts of Nicaragua and Guatemala, known by the names Papagallo and Tehuantepec, are, according to Ruprrenp, the fine-weather side of a whirlwind- storm, - while the S.W. gales in August and September, which are called Tapayaguas, represent the other side.

The indications of approaching weather will be most simple in the zone of the trade-winds, because the rotation of the earth, owing to the simple circumstance of the initial and terminal points of the aérial current remaining nearly the same, does not produce a regular shifting of the vane, but its constant deflection, viz., a steady wind - that of the trade; and the storms have only one form - a rotatory one. In the region of the monsoons they will be somewhat more complicated, because there two aérial currents, alternating once with each other in the year, pro- duce one annual shifting of the vane, being periodical winds; and the storms, the form of which is likewise rotatory, have consequently a less constant direction, and in fact it must differ in a certain degree from the prevalent one in order to produce a whirlwind. They must, lastly, be most complicated in the temperate zone, where the law of gyration is universally prevalent, but where storms also occur in all forms hitherto known. The temperate zone has, however, this advantage over the torrid zone, that whirlwinds produce but modified effects as compared with the fearful violence of storms of this description in the tropics, and where they are so destructive.

The relation of the winds to the temperature and pressure of the air will be discussed in a future chapter.

9. The Trade-Wind Region in the Atlantic Ocean :* - Although this work is principally designed to place before the Shipmaster such information as may be useful in the navigation of the Indian Ocean and the China Seas - where the number of regular traders, plying exclusively from port to port in those waters, has enor- mously increased of late years - still, the traftic between Atlantic ports and the East is so large and of such importance, that a general but brief notice of the distri- bution of the Trade Winds in the Atlantic Ocean is absolutely necessary, for the speedy crossing of this region may make all the difference between a long and a short voyage.

10. The average breadth of the Attantic TRADE-WIND RrGion - estimating it to extend from the mean polar boundary of the N.E. to the mean polar boundary of the §.E. Trade-wind - is about 53} degrees - 3195 geographical miles - z.e. from Lat. 277° N. to Lat. 26° S.

11. No fact is better known to the navigator than that the position - and even the » direction - of the Trade-winds greatly depends on the position of the sun in the

* This is introduced, as all shipmasters may not have an " Atlantic Directory :" - such a work is published by Messrs, ImRAY and Son : - in it the physical phenomena of the Atlantic are fully described, and " sailing directions " given for all the principal ports.

TRADE-WIND REGION - ATLANTIC, 13

Ecliptic - oscillating north and south, according as the sun has N. or 8. declination. The polar boundary of the N.E. Trade has a mean oscillation of five degrees,

. €. from Lat. 30° N. in August to Lat. 25° N. in January, but the position in which jt may generally be found at any of the four quarters of the year, and in any longi- tude between 15° and 75° W., is shown in the following table : -

TaBLE I. - Giving the Mean Polar Boundary of the N.E. Trade Wind in the Atlantic Ocean.*

| WINTER | SPRING. | SuMMER. AUTUMN. Long. Jan., Feb., March. | | April, May, June. | July, Aug., Sept. | Oct., Nov., Dec.

|

|

|

| |

| W. oo

Lat. N. | Lat. N. | Lat. N. Lat. N.

: fe) a ° ie) | oO ie)

| 75 273 | 29 294 282

| 70 26 | 292 29 273

| 65 24,8 252 | 288 263

60 22 23 | 254 25

| 5B 21 252 72 23

| 50 24, 27 31 26

| 45 27 | 302 302 30

| 40 26 28 292 26

| 35 25 | 281 284 242

| 30 24,2 253 314 221 25 224 274 294 25 20 273 31 332 28

| 15 298 33 342 292

| Mean 254 28 292 26+

12. The steady winds of the torrid zone (¢.e..the N.E. Trade in the northern portion, and the S.E. Trade in the southern) is divided into two parts by the intervening Zone of Calms: in the Atlantic ocean, not only is the oscillation of this zone very considerable - but its breadth during the northern summer is great; thus, the mean range of the equatorial boundary of the N. E. Trade varies between Lat. 10° or 12° N. (in August, September, and October) and Lat. 1° or 3° N. (in March and April), but it has been reported as far north as Lat. 17° N. and as far south as Lat. 3° S. The equatorial boundary of theS.E. Trade is more frequently found north of the equator than south of it, its mean position being in Lat. 3° or 4° N. on the western side of the Atlantic, and in Lat. 1° or 2° N. on the eastern side - and its range is small as compared with that of the N.E. Trade. The axis of the Belt of Equatorial Calms lies near the parallel of 5° N., which coincides with the greatest number of Calms as reported by Maury; and the mean breadth of this belt, for the whole year, is about 32 degrees (or 220 geographical miles), being the mean dis- tance between the equatorial margins of the two Trade-winds. A convergence of the two winds (N.E. and §.E.) takes place on the westerly meridians, and hence the Calm-belt is narrower on the western side of the Atlantic than on the eastern, These remarks are illustrated in the following table : -

* This is a table of double entry, but the headings explain themselves, - thus, during Autumn, in long. 20° W., the northern (or polar) boundary of the N.E. Trade Wind is in lat, 28° N= during Summer, in lat, 383° N,

TRADE-WIND REGION - ATLANTIC.

14

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TRADE-WIND REGION- - -ATLANTIC. 15

This differs but slightly from Horspureu's Table, derived from 100 voyages made within the range of the track of vessels outward and homeward bound between England and India: -

| t

Southern Northern Breadth boundary of | boundary of of the

| TABLE DERIVED FROM HoRSBURGH.

' : the N.E. the S.H. intervening

| a> Fetiod Of ae: Veer, Trade-wind. | Trade-wind. Zone. Q ! ry OF) fe) 1

1. January, February, March. .| 5 35 N. 145 N 3. 50 2. April, May, June . . i oe Pap 2.20 ON, 4 655 3. July, August, September . was: pede Lae Ny, SOLO as 9 0 4. October, November, December . Ae Ors 320 N 4 30 N 5 34

Annual. Mean = 20S PS taeP ., | 8 14 N. 2 40

In Table II. it will be noticed that the "breadth of zone' is sometimes marked C, and sometimes C. and §.W.; although this is the region of Equatorial Calms, yet a portion of this zone is, from May to November, occupied by the 8.W. Monsoon, and during July, August, and September it may be found as far as the parallel of 8° to 10° N.; it is wedge-shaped, with its base resting on the African coast, and its apex stretching to the meridian of 30° or 35° W.

a3. The S.E Trade-wind blows with great regularity, and is generally more persis- tent than the N.E. ; its polar boundary is given below : -

TaBiE IlI. - Showing the Polar Boundary of the SH. Trade Wind in the

Atlantic Ocean.

| SUMMER. AUTUMN. | WINTER. SPRING. | Bone. Jan., Feb., March. | April, May, June. | July, Aug., Sept. | Oct., Nov., Dee. RE Be ea Be oo stew tube eked lige aes eee phi SS ae Tats. Tabagl Lat. 8. Tava | ie) (@) @) ce) © | 45 W. 232 23+ 25% 264 40 231 23 26 264 35 22 213 23 24, 30 258 23 25 22 25 264 25+ 26+ 24,3 20 273 262 272 274 | 15 28 281 29 985 10 28 a74 283 288 5 W 282 29 283 282 0 262 25 24, 26 5 E 24,3 23 232 24 10 26 25 24,3 26 15 29 29 287 29

16 TRADE-WIND REGION - ATLANTIC.

24. The mean direction of the N.E. Trade-wind, in the Atlantic, between Lat. 5° N. and 30° N. is N. 523° E.; that of the S.E. Trade-wind, between Lat. 5° N. and 30° S. is S. 48° E.; and it must be remembered that between Lat. 5° N. and the Equator the N.E. Trade-wind does not blow for more than

85 days in the year.

15. These Tables (p. 13 to 15) may be aptly closed with Maury's Summary on tHE N. Artantic TrapE-Winp Raeion, in which, referring to the marked dif- ference in the prevailing direction of the wind, according to the season of the year, in the different parts of the ocean, he says that

" As a general rule it will be observed by the navigator -

1. That the nearer to the coast of Africa and to the Equator, the more the so- called N.E. Trade-wind hauls to the South.

2. That to the west of Long. 45°, between Lats. 20° and 30° N., the N.E. Trades blow much more steadily in May, June, July, August, and September than they do the rest of the year; and that during the other months, but particularly in March, they blow, between these parallels, nearly alike from all points of the compass.

3. That between Lats. 15° and 20° N. they are most variable west of Long. 35° in the months of September, October, and November; while between the same paral- lels, east of Long. 30°, they are most variable in February, March, April, and October.

4, That between Lats. 10° and 15° N., to the west of Long. 35° they are steadily between E.N.E. and8.H., except in July, August, September, October, and November, when they are more variable, but especially so in the three months first named. To the east of Long. 35°, between these parallels, they may be said to lose their character as Trades during July, August, September, and October, - particularly in August and September - when they blow nearly alike from the four quarters. Calms, too, are more frequent here in these months.

5. That between the Equator and 10° N., to the cast of Long. 35°, the winds assume a new feature. It may be said, almost literally, that in this part of the ocean they uniformly blow (when they blow at all), during July, August, and September, from some point between 8.E. and W.; they blow most between South and W.S.W., and vary rarely from any point between North and E.S.E. To the west of the meridian of 35°, during the same months, they blow most between S.E. and N.E., inclining more and more to the North as you go west; and these are the months in which the winds vary most in this part of the ocean."

The S.E. Trade-wind is generally more persistent, and blows with greater strength than the N.E. Trade-wind - hence it is of rarer occurrence for a captain to record in his journal "no §.E. Trade" than '' no N.E. Trade ;" the " heart" of the 8.E. Trade has been shown* to lie on each side of a line drawn from the Cape of Good Hope to the meridian of 36° W. on the Equator, - this is the track of all homeward-bound vessels that come from the Indian Ocean and China Seas, and they seldom have to record, no 8.E. Trade ;" it is generally outward-bound vessels, and those coming from Australia and the Pacific, that are doomed to this experience, for, by having to shape thei course on the 8.W. flank of that '' vein" of wind, they only fall in with it near the Equator; all, however, are in the same category as regards the N.H. Trade.

* See the reports of all homeward-bound East India and China traders ;. and the notice of the same by JANSEN, in MAuRy's '" Physical Geography of the Sea,"

TRADE-WINDS - PACIFIC, 17

Ti is scarcely necessary to make any remarks here on the Catm Betts or Cancer AND Capricorn; but, under all circumstances, endeavour to cross either the one or the other as direct as possible, never sailing along the line of one of these bands, nor even diagonally, if the wind will permit of a more meridional course.

16. The Trade-Winds in the Pacific Ocean: - A brief notice of the Trade- winds in the Pacific will complete our remarks on this subject. Table LV. is derived from the voyages of 92 vessels as determined by KErHALLET; Table V. is derived from Mavry's " Nautical Monographs," No. 1.

'Tastr IV. - Showing the Distribution of the N.E. and S.E. Trades, and Equatorial Calm Belts in the Pacific Ocean.

Polar Limit} Equatorial Boundary | Polar Limit of N.E. | of N.E. | of S.E. | Breadth | org a, Months, Trade-Wind/Trade- Wind|Trade- Wind E Ore. |Trade- Wind ie quatorial Calm Belt.| 7.4

Lat. N. Lat. N. Lat. N.

fe) / fe} ! ° ! Ons ° ! RHOAE YO ses cys EE eLO 6 30 Sas 30 33 25 BODTUAYY, G55 +5 ..> 28 28 4 1 ae ya 28 51 Ua eer 29 0 8 15 5 50 2 26 31 10 Oe 30 0 4, 45 2 0 2 45 27 25 Ieee + od of | ae Oo 7 52 3 36 4,16 28 24 GH Se ad oh wits |. ae ak 9 58 2 30 7 28 25 0 ees SU ot cs 31 43 12 5 5 4 (pe 25 28 maonsbe,. tS *. 29 30 15 O 2 30 12 30 24,18 September . . . 24, 20 13 56 idl 4 5 45 24 51 Soper <n os 26 6 12 20 3 32 8 48 23 27 November .. . 25 9 - _ - = 28 39 December .. . 24 0 5 12 1 56 3 16 20 30 Ist Quarter of Year*} 26 9 6 15 Sahat ie oo Bea tae ei es 28 55 7 32 242 | 4 50 26 56 3rd 4 - 28 31 13 40 5 15 8 26 24 52 Ath ny 25 5 8 46 244 | 6 2 24 51 Yearly Mean . .| 27 10 9.5 | 8389 | 626.) 2657

Taste V. - Showing the Distribution of the N.E. and S.E. Trades in the Pacific (in days, and as regards direction) between Lat. 10° N. and the Equator.

No. of | No. of | Bands in Latitude. Mean Direction of the Wind. ras Obs. Calm. Lat. 10° to 5° N. | N.54°E.| 8. 44° E. |S. 33° W.|N. 46° W. No. of days . . 143 134 54 ye ee 14,064 Lat. 5° N. to Eq. | N. 57° E.| S. 44° E. | 8. 30° W. | N. 42° W. | No.ofdays . .| 49 206 89 12 fog i 46162

* Phe seasons cannot be given here, for the table appertains to both hemispheres, consequently the seasons differ,

c

18 TEMPERATURE OF N. TORRID ZONE.

These Tables show that though the annual oscillation of the Trade-winds in the Pacific is not quite so great as it isin the Atlantic, still it is much more considerable, than is generally allowed; and further, that, between Lat. 10° and 5°N., the N.E. Trade can, on the average, be expected for only 9 days (the difference between 143 and 134 days) longer than the S.E. Trade, while between Lat, 5° N. and the Equator the S.E. Trade blows for nearly two-thirds of the year.

According to ComMANDER Maury, the 8.W. Monsoon is better developed in the Pacific than in the Atlantic; and the N.E. Trade-wind of the Pacific is better deve- loped than the S.E. Trade-wind of that ocean, or indeed than the N.E. Trade-wind of either the Atlantic or Indian Ocean,

217. The fact of the inner (or equatorial) boundary of the 8.E. Trade-wind crossing the Equator and advancing into the Northern Hemisphere has been noticed by navi- gators from an early date, - by Sxntar in 1675, by Dampier, by dVAprRis Ke.; now, it is well known to meteorologists that, owing to the preponderance of land in the Northern Hemisphere and the peculiar distribution of the Oceanic Cur- rents, the Equator oF GREATEST HEA' is in that hemisphere, but far from being a regular line, parallel with the terrestrial equator. According to Dovr* the mean temperature of the northern part of the torrid zone is as follows ; -

LATITUDE. | Monrus. 0 10° 20° 30° Therm Therm Therm Therm. January. «| 79°S°R.| 77: 2°R. | 700° 58°6° F. February .| 80'2 78°6 127 59°9 March . . 80'6 197 75°2 63°7 | April. . .| ara 811 79-0 682 Mays fs. 802 B1'3 80°6 13-6) 20 June . 79°9 sL'h Sih ii Ese July . | joe's 80°8 Si'7 fice August .. 78'8 80°8 817 =| 806 | September . | 79°0 soe | 806 77°5 October . . 790 80'2 | 79°0 72°9 November . 79'°7 7O"7 | 76°38 66°0 December . 79'3 78°4 | 73°0 59°7 | Winter Mean | soa | 788 | 72:6 | 60°7 Spring ,, 80°5 | 81'2 | 80°2 | 73°0 | Summer ,, 78'8 80'8 81'3 78°8 Autumn ,, 79'3 79'°% 761 662 Annual Mean 79°7 | 80'0 | 775 69°7 ! PAR eis i pees Wy

This Table shows the position of the place of greatest rarefaction for the different ~ months and quarters of the year. Thus, during the northern winter it is near the

* "Die Verbreitung der Warme auf der Oberfliiche der Erde," (The Distribution of Heat on

the Surface of the Earth.) Berlin, 1852,

WINDS OF THE INDIAN OCEAN. 19

Equator, - during the spring it has advanced to Lat. 5° and 10° N., reaching Lat. 10° to 20° N in summer (July and August), - after this its recession (southward) com- mences, being found in Lat. 10° N. during the autumn, as in spring, - and finally, again attaining the Equator in winter. This is precisely the march of the Equatorial Belt of Calms and of the inner boundary of the N.E. Trade-wind.

Since then the inner boundary of the 8.E. Trade-wind crosses the Equator and, from thermometrical causes passes into the Northern Hemisphere, it must advance more and more north (according to the season) following the place of greatest rarefaction ; and as it advances, its direction must change to South and S.W. because it is constantly approaching parallels on the earth's surface where the velocity of rotation is diminishing as compared with the velocity of rotation at the Equator. Hence the origin of the 8.W, Monsoon - alike in the Atlantic, Pacific and Indian Oceans - but best developed in the latter. Similarly, a N:W. Monsoon originates from the N.K, Trade-wind passing into the Southern Hemisphere.

18. WINDS OF THE INDIAN OCEAN. - GorneERAL RemarKs: - South- ward of the 30° parallel the N.W. Counter-Trades or " Passage Winds" are more or less prevalent throughout the year: between them and theS.K. Trade lies the Calm- belt of Capricorn. The 8.E. Trade, as in the Atlantic and Pacific Oceans, occupies the region from the Calms of Capricorn to within a few degrees of the equator - but undergoing in the Indian Ocean a slight modification on its northern border, according to the season of the year. The area northward of the 8.H. Trade is occupied by the Monsoon Region.

19. Ifonsoons are prevalent, between the tropics, in every ocean; in the Atlantic and Pacific they occupy the place of the Trade-winds only at a certain distance from the land (100 to 300 miles)* and during certain seasons ; but in the northern Indian Ocean they are the characteristic winds, to which the Trades are subordinate.

The distribution of land in the Indian Ocean differs widely from that in the other oceans. - As regards the Atlantic and Pacific, the continents run north and south. In the Indian Ocean, on the north there is the great central Asiatic plateau fronted by the loftiest mountains in the world, - then the two slightly elevated table-lands of Persia and Arabia, void of rivers, and comparatively destitute of vegetation, - southward of these and advancing into the ocean is the Indian peninsula, of which the Malabar (or western) coast rises abruptly from the sea, whilst the slope on the Coromandel (or eastern) side is gradual; - on the N.E. is Birmah, the Malayan peninsula and China, - the China sea is bounded by mountains on the north and by the Filipine archipelago on the east ; - then come innumerable islands, many of which are lofty and mountainous ; - finally, on the east of the Indian Ocean is the Australian continent, on the west the African continent : - it is this configuration of the land that has caused the Indian ocean to be regarded as only half an ocean, and it is this preponderance of the terrestrial over the oceanic element that disturbs the regularity of the Trade- winds and produces opposite seasons (wet or dry) to places even on the same parallel.

Thus, it is the preponderance of the land and the difference of temperature con- stantly existing between it and the neighbouring ocean which produce the season- breezes - known as Monsoons.+ No other winds than these, and land and sea breezes,

* Monsoons are prevalent, in a modified form, alike on the west eoast of Africa and the west coast of America, during the summer of the region. + Arabic, mausim, season, o2

20 WINDS OF THE INDIAN OCEAN.

are recognised in the China sea and Indian archipelago; but in the Indian ocean, the Monsoon region is limited to its northern part - extending from Lat. 13° or 10° S. to the Asiatic continent.

Speaking in general terms, it may be said that, north of the equator, a north- easterly wind prevails when the sun has southern declination, and a south-westerly wind when the sun's declination is north, - the former is the N.E., and the latter the S.W. Monsoon of the region; but between the equator and Lat. 12° 8S. a N.W. Mon- soon is prevalent when the sun has south declination, and a 8.E. Monsoon when his declination is north: thus in each hemisphere there are two season-winds - of variable duration, according to the position of the place and the surrounding physical features: - in no case does one Monsoon terminate abruptly and the other commence forthwith, but there is a period of change known as the breaking wp of the Monsoon; when one season-wind is about to cease it decreases in force and is occasionally replaced by calm; the atmosphere at sea and on the land shows evidence of disturbance; the sky is overcast and the air becomes sultry, oppressive, and foggy; the clouds of the upper region move in the direction of the succeeding Monsoon ; and as the change progresses the wind becomes more and more variable. The following description of this phenomenon, " the breaking up of the Monsoon," is aptly depicted by Sir J. E. TENNENT, in his work on " Ceylon.''*

'Meanwhile the air becomes loaded to saturation with aqueous vapour drawn up by the augmented force of evaporation acting vigorously over land and sea: the sky, instead of its brilliant blue, assumes the sullen tint of lead, and not a breath disturbs the motionless rest of the clouds that hang on the lower range of hills. At length, generally about the middle of the month, but frequently earlier, the sultry suspense is broken by the arrival of the wished-for change. The sun has by this time nearly attained his greatest northern declination, and created a torrid heat throughout the lands of Southern Asia and the peninsula of India. The air, lightened by its high temperature and such watery vapour as it may contain, rises into loftier regions and is replaced by indraughts from the neighbouring sea, and thus a tendency is gradually given to the formation of a current bringing up from the south the warm, humid air of the Equator. The wind, therefore, which reaches Ceylon comes laden with moisture, taken up in its passage across the great Indian Ocean. As the monsoon draws near, the days become more overcast and hot, banks of clouds rise over the ocean to the west, and in the peculiar twilight the eye is attracted by the unusual whiteness of the sea-birds that sweep along the strand to seize the objects flung on shore by the rising surf.

" At last the sudden lightnings flash among the hills and sheet through the clouds that overhang the sea, and with a crash of thunder the monsoon bursts over the thirsty land, not in showers or partial torrents, but in a wide deluge, that in the course of a few hours overtops the river banks and spreads in inundations over every Jevel plain.

'All the phenomena of this explosion are stupendous; thunder, as we are accus- tomed to be awed by it in Europe, affords but the faintest idea of its overpowering grandeur in Ceylon, and its sublimity is infinitely increased as it is faintly heard from the shore, resounding through night and darkness over the gloomy sea. 'The light-

* " Ceyton: An account of the Island - Physical, Historical, and Topographical, &c.'' By Sir James Emerson Tennent, K.C,S. U.1.D. (1859.)

WINDS OF THE INDIAN OCEAN. 21

ning, when it touches the earth where it is covered with the descending torrent, flashes into it and disappears instantaneously ; but when it strikes a drier surface, in seeking better conductors, it often opens a hollow like that formed by the bursting of a shell, and frequently leaves behind it traces of vitrification. In Ceylon, however, occurrences of this kind are rare, and accidents are seldom recorded from lightning, probably owing to the profusion of trees, and especially of cocoa-nut palms, which, when drenched with rain, intercept the discharge, and conduct the electric matter to the earth. The rain at these periods excites the astonishment of a European ; it descends in almost continuous streams, so close and so dense that the level ground, unable to absorb it sufficiently fast, is covered with one uniform sheet of water, and down the sides of acclivities it rushes in a volume that wears channels in the surface. For hours together, the noise of the torrent as it beats upon the trees and bursts upon the roofs, flowing thence in rivulets along the ground, occasions an uproar that drowns the ordinary voice and renders sleep impossible.'

20. Before proceeding to give a detailed account of the winds in the different regions of the Indian Ocean, it may be useful to draw up a Summary of the 'Winds in the Monsoon Region; they are as follow : -

During the sumMER Monts of the Northern Hemisphere the S.E. Trade-wind is prevalent i in the southern part of the torrid zone,* - and the 8.W. Monsoon blows in full force in its northern part.

During the wintER MontTuHs of the Northern Hemisphere the N.W. Monsoon prevails in the southern part of the torrid zone, - and the N.E. Trade-wind is in full strength in its northern part.

The N.E. Trade-wind, however, is, in these regions, called the N.E. Monsoon, - and the S.E. Trade-wind, the §.E. Monsoon. As shown in sec. 19, p. 19, the N.E. Mon. soon gradually and by degrees glides into the N.W. Monsoon, - and the 8.E. Monsoon into the S.W. Monsoon. And thus the Monsoons of the Indian Ocean are not separated by any such distinctly-detined belé of cals as is interposed between the Trade-winds of the Atlantic and Pacific Oceans. A Belt of Calm is to be found in the middle of the Indian Ocean, but it exists under different circumstances from that in either of the two other oceans, - and its range is more varied, - might be expected where the winds are seasonal and not perennial.

In the Sprine and Autumn of the Northern Hemisphere - in the months when the Monsoons change - calms and variable winds prevail in the open ocean; and daily Jand-and-sea breezes along the coasts, from which, however, they extend but a few leagues ; as soon as the Monsoon becomes regular and blows in its strength the Sitineiive land-and-sea breezes may be said to cease. In this ocean the land-breeze usually commences about midnight and terminates at sunrise, - the sea-breeze blowing from about mid-day until near sunset; both are moderate, but the sea-breeze is much fresher than that from the land.

The season of change from one Monsoon to the other varies in different parts of the Indian Ocean. This can be readily conceived from the physical characters (see sec. 19, p. 19) to which we have already adverted; being much more exposed than the other oceans to the disturbing influences consequent upon proximity to land,

* The torrid zone extends from Lat. 28}°N. to Lat. 234° §,, and may be considered as divided into two parts - a northern and a southern - by the equator.

22 WINDS OF THE INDIAN OCEAN,

the winds are consequently affected in a proportionate degree by doca/ conditions. Thus the S.W. Monsoon stretches into the Northern Hemisphere much further to the North (as far as Lat. 30°) than the N.W. Monsoon into the Southern Hemisphere. Along the Arabian and Hast African coasts, and also along the N.W. coast of Australia the Monsoons assume in each case a direction which is dependent on the contour of the land and the peculiar physical features of the interior of the con- tinents. In the Red sea the Monsoons blow alternately up and down, following the direction of the long, trough-like valley, within which the currents of air are confined. In no case is it correct to say that any one of these Monsoons blows for six months; they may prevail each for five months, but in many places not for more than four months - the intervening period being characterized by variable winds, with alternating calms, or squalls, and occasional cyclones.

The Monsoons of the Cu1na Sua - (z.e. N. of the Equator) - are not entirely similar to those of the Indian Ocean; they may be divided into three periods -

1. The N.E. Monsoon, in October, November, December, and January, - changing in February.

2. The East Monsoon, in March and April, - changing in May,

3. The S.W. Monsoon, in June, July and August, - changing in September.

In the Java Sua and among the islands of the InpDIAN ARCHIPELAGO (ze. 8. of the Equator) S.-Easterly winds prevail while the sun is in the Northern Hemisphere, and these are replaced by N.-Westerly during the stay of that luminary in the Southern Hemisphere ; the former are known as the East Monsoon and the latter as the West Monsoon - and are characteristic of all that region by which the South Pacific communicates with the Indian Ocean: Comparing together the seasons of the two tropics, the West Monsoon (S. of the Equator) corresponds with the N.H: Monsoon of the Indian Ocean and China Sea, - the Hast Monsoon is the repre- sentative of the 8.W. Monsoon.

21. The Seasons (wet and dry) within the Monsoon region are, in a great mea- sure, determined by the direction of the wind (¢.e. whether the direction of the air- current has come over the land or over the ocean); or perhaps it would be more strictly accurate to say that they are concurrently dependent on the Monsoons and the lay of the land. The west coast of India (Malabar coast) has its rainy season during the prevalence of the $.W. Monsoon; no portion of the rain at this season passes the Ghauts or central table land of India. Along the east, or Coromandel coast of this peninsula it is the N.E. Monsoon that brings rain, which waters the country to the summit of the eastern flank of the Ghauts. Thus the two coasts of the peninsula have their seasons reversed ; one has the dry season when the other has the rainy season, and reciprocally: similar facts appertain to all countries within the Monsoon region of the Indian Ocean, - and even in a diminished degree to the islands - especially such as Ceylon, Borneo, and those of the largest class.

22. We may appropriately close this chapter with the following Table of the WINDS AND Cams IN THE INDIAN OcEAN, from Maury's " Nautical Monographs," No. 1; - it gives the total number of observations in each band of latitude, the mean direction of the wind from each quarter, and the average annual duration of each wind m days. Itis a table to which we shall have occasionally to refer.

WINDS OF THE INDIAN OCEAN. 33

| No. of Wasa | Bands in Latitude. Mean direction of the Wind. days of ait | | Calin. | Lat. 25° to 20° N, | N. 41° HR. | S. 42° KE. |S, 43° W. | N. 40° W. W.. | No. ofdays. . .| 84 54 148 _ | 66 | 13 | 1874 | Lat. 20° to 15° N. | N. 42° E.| 8. 47° E. ty 46° W.| N. 44° W. | | mer orddys'. y= ade 36 145 | 657 11 | 6800 Lat. 15° uy 10° N. | N. 46° E. | S. 46° B. | S. 47° W. | N. 45° W. Nes. Of Gays sins 127 52 123 51 12 7483 Lat. 10° to 5° N. . | N. 44° HE. | S. 47° EH. | S. 50° W. | N. 52° W No. of days. . . ET} 42 140 60 12 8841 Lat. 5° N. to Hq. . | N. 41° H./ S. 41° E. |S. 46° W.| N. 51° W No. ofdays. . . 82 60 _ 138 67 18 9369 Lat. Eq. to 5° N,. 46° E, | 8. 42° E. | 8. 44° W. | N.51° W. No. of days... 49 124 | 96 71 25 | 14,264 Lat. 5° S. to 10°S. | N, 53° E.| 8. 48° E. | S. 38° W.| N.51° W No, of days: 7. . 51 178 63 54, 19 | 16,618 Lat. 10°S. to 15° S. | N. 60° E. | 8. 45° HE. | S. 41° W. | N. 50° W No. of days . : 37 24,1 4, 27 13. | 18,028 | Lat. 15°8. to 20°S, | N. 67° H.| 8. 50° E. | 8. 34° W.| N. 46° W No. of days. . 43 272 34, 10 6 | 17,340 Lat. 20° to 25°S. . | N. 62° H.| 8. 49° E. | 8. 29° W.| N. 42° W No.ofdays. . . 83 215 40 18 9 | 31,965 | Lat, 25° to 30°S. . | N. 54° B.| 8. 48° B. |S. 36° W. | N. 40° W No. of days . : 108 146 62 39 10 | 33,160 Lat. 30° to 35° 'S. . | N, 45° H,| 8. 48° EB. |S, 44° W. | N. 48° W MOL OLGaAySs. . 75 84 : 113 83 10 | 26,249 Lat. 35° to 40° S.. | N. 39° H. | 8. 44° E. |S. 41° W. | N. 51° W moor days'. ss". 49 52 128 129 7 | 56,336 Lat. 40° to 45° S.. | N. 82° EK. | 8. 39° E. | S. 54° W.| N. 48° W 5 No. ofdays. . . 47 20 : 126 167 5 | 18,623 Lat. 45° to 50° S. . | N. 38° E. | 8. 49° E. |S. 53°W. | N.51° W No. of days . 62 | ae tts OE 161 6 6333

CHAPTER III. WINDS IN THE INDIAN OCEAN.

23: The wrnp REGIONS of the Indian Ocean may be classed under four well: marked heads, which, commencing from the south, are - 1, The Region of the N.W. Passagu-Winps, usually found to the south- ward of the 32nd parallel ; 2. The Region of S.H. TrapEe-Winp, between 32° or 30° S., and 12° to 10° S. ; 3. The Region of the S.E. and N.W. Mowsoow, between 12° or 10° S. and the Equator or 3° N.; 4. The Region of the N.E. and 8.W. Monsoon between the Equator and the Asiatic Continent ; - Each of these wind-regions will be treated separately, after which a general description of the winds along the coast will be given in detail, | It may be as well, at this point, to draw attention to and explain the Cuart

24. WINDS OF THE INDIAN OCEAN.

DIAGRAMS OF THE Winps which have been prepared for this work: they are dfawn for each of the four quarters of the year, - Cuart Diagram No. I. embracing October, November, and December.

i No. II. $ January, February, and March. 4 No. ITI. ;; April, May, and June. y No. 1V. " July, August, and September.

By this arrangement, Nos. I. and II. give the period of the N.E. Monsoon, and Nos. III. and IV. the period of the 8.W. Monsoon. The direction of the arrows shows the point towards which the stream of air is moving. These diagrams are chiefly com- piled from the Boarp or Trapr and Maury's Wind-Charts, modified by the observations contained in the Log-books in the possession of the Author, which con- tain about 300,000 eight-hourly observations. The area of the ocean is generally divided into squares of ten degrees of latitude and ten degrees of longitude, except where well-marked differences in the direction of the air-currents require a sub- division into squares of five degrees of latitude and longitude; the numbering of the ten degree squares of the Board of Trade Wind Charts, has also been retained in the letter-press, for the purpose of reference.

SS ers

24. REGION oF THE N.W. Passacn-WINDS - SOUTHWARD OF Lat. 32° 8.

In the most southerly portion of this region, ¢.e. in latitudes higher than 55° 8. (the Polar region), winds from the N. and S. are equally prevalent with a greater tendency to blow from the eastward during the swmmer (December to March), but from the westward during the winter (March to December).

Between lat. 40° and 50° 8. the winds are generally from the westward - between W.N.W. and W.S.W., the former predominating (see Table, p. 23); easterly winds are frequent during the summer, but calms and light baffling airs are rare; the storms of this region are at times very heavy and may be expected at any season. This part of the ocean is represented on the CHart DraGrams by areas Nos. 56 to 65, both inclusive.

Between Lat. 30° and 40° S. the winds are still, as a rule, westerly, but the in- fluence of the African and Australian continents is very perceptible - as indeed is the effect of the warm current from the Indian Ocean - producing a diversion of the main stream of air towards the region of greatest rarefaction. This is well seen in the Cuart Dracrams, IJ., IL., II., and IV. (areas Nos. 46 to 55, both inclusive) where, in mid-ocean, the prevalent winds may be said to be between N.W. and S.W. ; but on the African side of the ocean, westward of long. 70° E., easterly winds (E.N.E. to8.8.E.) are very common from November to March; during April, May, and June, these easterly winds scarcely extend beyond the 45th meridian, and during July, August, and September, they are very rarely experienced. Similarly, the areas in the vicinity of the Australian continent are characterized by winds between W.N.W. and 8.S.W. - drawing towards and along the land. Easterly winds may, however, be expected more or less along the whole of this band (lat. 30° to 40° 8.) during the Southern summer - December to February.

Between the parallels of 25° and 35° S. is situated the polar boundary of the 8.E. Trade-wind, oscillating with the march of the sun in declination; between these parallels is also the place of the Catm BAND or Capricorn - its mean position and average breadth being shown on the Cuart DraGrams, as well as its tendency to

WINDS OF THE INDIAN OCEAN. 25

expand, where it nears the African coast: by reference to Table, p. 23, it will be seen that in this band there are 10 calm days in the year, on an average. Between Lat. 35° and 40° 8. the N.W. and §8.W. winds blow an equal number of days (129 each), - the S.W. predominating over the N.W. between Lat. 35° and 30° &. in the ratio of 113 to 83. Considerable unsteadiness in the S.E. Trade is shown on its polar limit between 30° and 25°S,, by not being prevalent more than 146 days, while winds between N, and E. are experienced for 108 days.

25. Tar Recion or tHe S.E. TRADE-WIND.

The region of the S.E. Trade-wind in the Indian ocean is comprised between the Calm Belt of Capricorn and lat. 12° to 10° S. (See CHart Diacrams I, II., IIT, IV., areas 30 to 36, and 38 to 44); the area of the ocean between 50° KH. and the African coast is only partially affected by this wind, - the disturbing cause being the high land of Madagascar in close proximity to the African continent; but the greatest modification of the Trade-wind occurs in the Mozambique Channel, as will be shown presently. The S.E. Trade-wind does not touch the west coast of Australia - the general winds on that side of the Southern Indian Ocean, and for fully 400 miles from the land, being from N.N.W. to 8.8.W. according to the season.

26. OFF THE CAPE oF Goop HoPpk AND THE HAstTERN Coast oF SoutH AFRICA. Lat. 50° S. to tHE Equator, Lone. 15° to 60° E.

A glance at the four CHart Diagrams will convince the reader that there are at least three systems of winds prevalent, more or less, over the oceanic area bounded by the Equator and Lat. 50° S., and by the meridians of 10° and 60° E. One of a very peculiar character sweeps from the neighbourhood of Cape Aguihas to the northern part of Mozambique, and this, with but slight interruptions, is maintained all the year round ; it appears closely to follow the coast-line - or more properly speaking, the line of table-land, which runs nearly parallel with the coast, and at a distance from it of about 100 or 150 miles. This air-current terminates in the summer (Southern Hemisphere) near the centre of the Mozambique Channel: in the winter it is continued to the Equator.

The northern part of the area, skirting the African coast, is characterized during the southern summer, from October to March, by N.E. winds, but winds from E.N.E. are found as high as 30° S. lat. during the six months: during the succeeding six months these winds are replaced by the S.E. trade.

It will be seen on Cuart Diracrams Nos. I. and II, that during the six months of summer, in the northern part of the Mozambique Channel, there is a point of con- vergence of the winds which sweep along the eastern coast of Africa, - in fact, that in this immediate locality there is a rarefying surface producing, in all probability, an ascending and upward current; notwithstanding that a N.E. wind penetrates to the parallel of Cape Corrientes, during the months of October to December, the directions of the arrows on areas Nos. 38 and 31 indicate that the wind along the eastern coast of Africa really converges to the north of the Mozambique, and that there N.E. and S.W. currents meet and ascend - and, as a consequence, frequent calms ensue in that part.

In the MozamBiquu CHAnnet it is difficult to say what Monsoons are prevalent ; but that which goes under the name of the N.E. is variable between N.E. and N.W. -

26 WINDS OF THE SOUTH INDIAN OCEAN.

it commences in November and ends in March: variable winds are more frequent in the southern part of the channel during this season than in the northern, for to the north of Mozambique the winds are generally from N.H. to N., accompanied with rain and squalls. At the southern entrance to the channel the variable N.E. to N.W. winds not unfrequently encounter the fresh 8. and 8.E. winds blowing on the south coast of Madagascar; under these circumstances severe gales of the rotatory type may be experienced, and the navigator should be prepared for them. This is the rainy season in the Mozambique Channel.

The so-called $.W. Monsoon commences in the Mozambique Channel in April and terminates towards November; this is the fine season. At the southern entrance to the channel the winds are 8. and §.S.W., becoming more westerly towards the northern entrance, and finally uniting with the S.W. Monsoon, which is at this season prevalent over the northern part of the Indian Ocean: but at times these winds are variable, as, for instance, from §.W. toS,E. and E.S.H. - those from the last direction being squally and strong off the south end of Madagascar. Near the coast of Africa this is the period of land-and-sea breezes. In mid-channel both Monsoons are more regular than along the coast.

South of the parallel of 30° S. is the general region of the N.W. '' passage-winds :" these also require a separate quarterly notice; they are of great importance to all commanders sailing to Australia, as the track to that important colony les through the heart of these winds, and the voyage to India and China is also accelerated by pursuing this track. We have already alluded to E.N.E. winds being found as high as 30° 8. lat. (see CHart Diagram No. L., areas 38,39). On the same Cuart Diacram, areas 47, 48, 49 are characterized by W.S.W. winds - eaactly the opposite; here to all intents and purposes there is an ascending current, and it would appear that the surface of the ocean in the neighbourhood of the parallel of 30° S. and between long. 80° and 50° E. becomes during the three months, October to December, sufficiently heated, as compared with localities north and south of it, to produce an indraught of cooler air from E.N.E. and W.8.W. This does not occur in the more open spaces of the Indian Ocean to the eastward. It isin the neighbour- hood of the parallels 30° to 35° 8. that Com. Maury places the Calms of Capricorn, and it is well known that he explains these, as well as the Calms of Cancer, by a descending current ox rather by two descending currents resulting from the meeting of two opposite currents in the upper regions of the atmosphere, which come out on the-surface, as two opposite winds blowing away from each other, thus - & - =>

The second meteorological axiom announced by Capt. Coartes Wi1xKes, U.S.N., in his " Theory of the Wind," is as follows: '" that if the atmosphere is disturbed by any change of temperature, the dewser and colder portions seek the warmer, from every direction, to restore the equilibrium 7" the most direct lines it can follow."

It is not intended on this occasion to enter into any examination of the controversy between Com. Maury and Carr. WiLKus; our object is of a more practical nature - to show the navigator the principal winds he may meet with, in various localities, as he prosecutes his voyages, and the connexion that exists between these winds and certain other physical phenomena, by which he may the more readily take advantage of such winds as may be suitable for his purpose.

Tn immediate connexion with the locality under consideration, HorspurGH has this remark; "The late Carr. J. Wixson, of the Company's ship Hythe, a very scientific officer, has ascertained by careful observation that the temperature of the central

WINDS OF THE SOUTH INDIAN OCEAN. 27

part of the stream of westerly current which prevails upon the verge of Cape Aguihas bank, is about 8° or 9° higher than that of the sea beyond the stream of current, and as the maximum of temperature is in the middle of the stream of current, a ship may be kept in it by attending to changes of temperature in the surface water, and hereby be enabled to accelerate her progress to the westward during adverse winds."

Mavry, in his " Physical Geography of the Sea," edition 1864, page 195, sections 393-4, speaking of a current of warm water in the Indian Ocean, says, '' There is some- times, if not always, another exit of warm water from the Indian Ocean. It seems to be an overflow of the great intertropical caldron of India, - seeking to escape thence, it works its way polarward, more as a drift than as a current: this Indian overflow is very large... and finds its way south, midway between Africa and Australia, and appears to lose itself in a sort of Sargossa Sea, thinly strewed with patches of weed. Nor need we be surprised at such a vast flow of warm water as these ¢hvee currents indicate from the Indian Ocean, when we recollect that this ocean is land-locked on the north, and that the temperature of its waters is frequently as high as 90° Fahr. There must therefore be immense volumes of water owing into the Indian Ocean to supply the waste created by these warm currents.

"On either side of this warm current that escapes from the intertropical parts of the Indian Ocean, but especially on the Australian side, an ice-bearing current is found wending its way from the Antarctic regions with supplies of cold water to modify climates and restore the aqueous equilibrium in that part of the world."

On turning to the chart of sea drifé (Currents of Indian Ocean), we find indicated a stream of warm water flowing from the eastward between Australia and Borneo ; this is divided into three branches ; - one goes north to the Arabian Sea and Bay of Bengal, at least during a part of the year; another goes south, to the Sargossa Sea before spoken of; anda third moves west, - a prolongation of this forms the _ Agulhas current before mentioned: and as the temperature of the central part of this current is 8° or 9° higher than that of the water on either side, so it is to be inferred, and most probably such inference is not far from the truth, that the Indian Ocean is parcelled out by these currents into portions of warm and cold, or at least cool water. We have now only to apply W1LKEs' axiom before quoted, and we see at once, that according to this axiom, the wind must blow from the cooler towards the warmer areas; such a warm area most probably exists in the neighbourhood of 30° S. between the areas Nos. 38, 39, and 40 on the north, and areas 47, 48, and 49 on the south ; in fact, this supposed warm area is in the line of the warm water current,

Whatever evidence may exist in support of Maury's idea, that the Calms of Capricorn and Cancer are produced by opposite winds meeting in the higher regions of the atmosphere and seeking the surface by a downward current, - here, in the region of the southern calms, there is evidence of at least one movement of an oppo- site character, - for the meeting of the E.N.E. and W.S.W. winds could not result in any way from a descénding current, nor is it easy to see how two parallel but oppositely directed currents could be produced by such means; the current exhibited onthe Cuart D1scGram being of this character, as will be shown further on. To proceed with the analysis of winds : - .

During the next three months, é.e. from January to March, the same opposition of the E.N.E. and W.S.W. winds obtain, although somewhat considerably modified by

28 WINDS OF THE SOUTH INDIAN OCEAN.

the position of the sun, - see CHart Diacram No. II. Between Lat. 20° and 40° 8, (in areas Nos. 40, 49, and 48) the prevalent winds are from E.N.E. or N.N.H., while in avea No. 39 and also in 49 we have it from E.S.E. It is in the parallels between 40° and 50° S., that the opposing wind from W.S.W. occurs, and this would indicate that the partial belt, or zone of warm water, above mentioned, had seceded From the Equator with the sun.

During the winter season in the southern hemisphere, this peculiar arrangement of the winds, arising from the presence of warm and cold water, disappears. Between April and June the S.H. Trade is fully established over the northern part of Cuart Diacram No. III., - and the breadth of the sweep of winds along the African coast is greatly augmented; it may be seen stretching as far as areas 49 and 39, and the arrow in 40 clearly shows the tendency of the stream of air to the great rarefying surface of the central part of South Africa.

During the months of July, August and September, - the Southern winter - a very remarkable arrangement of the wind occurs, as seen in CHart Diacram IV. Taking the space between lat. 20° and 30°S. as a sort of central area, we have the winds blowing towards the north on the north of it, and towards the south on the south of it; - those blowing towards the north are clearly the 8.E. Trade, which at this season reaches the Equator as the 8.E. Monsoon. It would appear that some powerful force exists at this period of the year, considerably to the south of Africa, and that this force draws the air from the north of 30° S. (area 40) in a curved sweep touching the southern extremity of Madagascar (area 39) and merging into a general N.N.E. current, as seen in aveas 48, 58, and 39; how far this northerly cur- rent extends, or in what it results, we have at present no evidence to show, except that it probably has its explanation in the warm water current, which flows almost due south on the meridian of the Cape at this period of the year.

We have thus noticed the three principal systems of winds, as indicated by the Cuart Dracrams; there is, however, another feature of no little interest, exhibited on all the diagrams; it isa kind of out-blow in the neighbourhood of the Cape of Good Hope, as shown by the arrows in the upper corners of areas 46 and 47; the different directions of the arrows clearly indicate the coldness of the land in the neighbourhood of the Cape and of South Africa, as compared with the warmth of the adjoining waters.

It is probable that this out-blow, which is seen on the four Cart DiaGRAMs, and consequently exists all the year round, is occasioned in some degree by the current of cold water which Capt. S1r JAMES CLARKE Ross found running in a northerly direc- tion along the west coast of Africa. We give the following abstract from that officer's journal.

"March 7. A gradual diminution of temperature of air and sea as we approached the coast of Africa. - At midnight, entered a cold mist, - water discoloured, but no soundings with 130 fathoms of line."

"March 8. Latitude 32° 21' §., Longitude 17° 6' E. - 45 miles from Paternoster Point, - soundings 127 fathoms. - Expected an elevation of temperature, both of air and sea, on approaching the African coast, by reason of the radiation of heat from its shores, - by 1 p.m. the temperature of the sea had fallen from 70° to 56.5°, that of the air being 65°, - The cause of the depression of temperature became evident on sighting Cape Paternoster, for a current increasing in strength and coldness as we neared the land was found to exist. The following is a summary of the experiments

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WINDS OF THE SOUTH INDIAN OCEAN. 29

on it: The current barely reaches 40 miles from shore - where the sea is more than 300 fathoms deep - but spreads over double that distance in shallower parts ; - 45 miles from land, at a depth of 120 fathoms, the temperature of the water was 40°, that of the surface being 56°; and 60 miles off land, at 200 fathoms, it was 43°5°, the surface being 61°; - thus a northerly current of very limited extent, but of considerable force, exists from the Cape of Good Hope along the west coast of Africa, which in general terms may be represented by a volume of water 60 miles wide and 200 fathoms deep, averaging a velocity of amile an hour . . . . running between the shores of Africa and the waters of the adjacent sea. The mist which hangs over the stream of cold water is occasioned by the condensation of the vapour of the superincumbent atmosphere whose temperature is generally so many degrees higher than that of the sea."

The temperature of the atmosphere first quoted is 65°, that of the surface being 8°5° lower; at 45 miles from land we find the surface temperature also 56°, but at 60 miles, ¢.e. 15 miles further, it is as high as 61°; it is probable the temperature in- creased still further out at sea, so that the natural effect of the heated sea-water (adjacent to the cold current) would be to draw the air from the coast, 7.e. to produce the western part of the out-blow noticed, the eastern part being due to the general westerly current.

Having sketched out the general distribution of the winds in the western part of the southern Indian Ocean, the next consideration is to specify the phenomena of each area of ten degrees square, and in so doing first to pass in review the stream of air sweeping along the eastern coast of Africa, - next, the opposing winds in the neighbourhood of the 30th parallel, - and lastly the S.E. Trade.

CHart Dracram No. I., October, November, December. (The Sowthern Spring.) Winds along the Eastern Coast of Africa : -

* 466, Area included between Lat. 30° and 35° S., Long, 15° and 20° E.

Prevailing wind, 8.8.E.

Frequent winds, E.S.E. - S.E. - S.S.E, (442.) The wind in this area blows mostly towards and along the land.

46d, Area included between Lat. 35° and 40°S., Long. 15° and 20° E,

Prevailing wind, W.N.W. .

Frequent winds, 8.S.E. - S.8.W. - W.S.W. (442.) The prevailing wind in this area is a portion of the general stream from westward between the parallels of 30° and 40° §,

47, Area included between Lat. 30° and 40° S., Long. 20° and 30° E.

Prevailing wind, W.8.W.

Frequent winds, 8.8.W. - W.N.W. - E.S.E. (441.) Here there is an indi- cation of the stream of air sweeping round the southern part of Africa, as well as atendency to the area of heated water mentioned on p. 27; the E.S.E. wind is in the direction of the same wind that blows outward from the land in area No. 46.

38d. Area included between Lat. 25° and 30° S., Long. 35° and 40° FE. Prevailing winds, 8.8.W. - S.S.E. - E.N.E.

* The numbers before the word " area" refer to the numbers on the Cuarr DIAGRAMS which secompany this work ; the numbers in brackets are those on the Board of Trade Wind Charts.

30 WINDS OF THE SOUTH INDIAN OCEAN.

Frequent winds, N.N.E. - E.S.E. (404.) In this area the winds generally set towards the African coast, although one of the prevailing winds is along shore, this is very similar to the winds in the adjoining area, and is in decided contrast with those in avea No. 48, where the set is outward, from the land,

88c, Area included between Lat, 25° and 30° S., Long. 30° and 35° K,

Prevailing wind, S.S.W.

Frequent winds, E.8.E. - E.N.E. (404.)

384, Area included between Lat. 20° and 25° §., Long. 35° and 40° E.

Prevailing wind, N.E.

Frequent winds, 8. - S8.S.E. and E. (404.) The winds from the eastward seem to indicate a point of convergence or rarefaction on this part of the African continent.

31c, Area included between Lat. 15° and 20° §., Long, 40° and 45° E.

Prevailing wind, 8.S.E.

Frequent winds, 8. - S.8.W. - 5.W. - N.N.E. (367.)

3la., Area included between Lat. 10° and 15° S., Long, 40° and 45° KE,

Prevailing wind, N.N.W.

Frequent wind, E.N.E. (367.)

31. Area included between Lat. 10° and 15° §., Long. 45° and 50° E,

Prevailing wind, N.E.

Frequent winds, 8.E. - H.8.E. - E. - N.N.E. (367.)

Tn the three latter areas we see the play of the winds in the northern part of the Mozambique Channel. In avea 31a the prevailing wind is outward from the land, but in the other two towards it. Areas 31a and 31d are subject to frequent calms.

The so-called N.E. Monsoon : -

22d. Area included between Lat. 5° and 10°S., Long. 35° and 40° E.

Prevailing wind, N.E.

Frequent winds, 8.E. - E. - -E.8.E. (332.) Stream of air from eastward,

23. Area included between Lat. 0° and 10° 8., Long 40° and 50° E,

Prevailing wind, N.E. and $.8.E.

Frequent winds, N.N.E. - E.N.E. - E. - E.8.E. - 8.E. - S. (331.) In this area the set of the wind towards the land is unmistakeable. Calms are very frequent during the three months. Similar remarks appertain to areas 31a and 31, to which the N.E. Monsoon probably extends.

Opposing currents of air in the neighbourhood of 30° S: -

39. Area included between Lat. 20° and 80° 8., Long. 40° and 50° E,

Prevailing wind, E.N.E.

Frequent winds, 8.8.E. - S.E. - E.S$.H. - H. - N.E. - N.N.E. (403.)

40, Area included between Lat. 20° and 30° 8., Long. 50° and 60° E.

Prevailing wind, E.N.E.

Frequent winds, E.S.E. - E. - N.E. - N.N.E. (402.) It will be observed that in area No. 39 there is a greater spread of wind than in area 40; in both, however, the general stream is from eastward; and probably as it approaches the land it is more divided, being subject to more numerous influences, . |

WINDS OF THE SOUTH INDIAN OCEAN, 31

48, Area included between Lat. 30° and 40° 8., Long. 30° and 40° BE. Prevailing wind, W.S.W. Frequent winds, $.8.W. - S.W. - W.N.W. - N.N.W. - N.N.E, - E.N.E, (440.) 49, Area included between Lat, 30° and 40° §., Long. 40° and 50° E. Prevailing wind, W.S.W. Frequent winds, 8.8S.W. - W.N.W. - N.N.W. - N.N.E, (439.) 50. Area included between Lat. 30° and 40° S., Long. 50° and 60° E. Prevailing wind, N.N.W. Frequent winds, 8.8.E. - S8.8.W. - W. 8.W. - W.N.W. (438.)

The direction of the arrows in the three last aveas indicate a general movement of the air from the westward, and consequently in a nearly opposite direction to the movement of the air in aveas 39 and 40. The movement of the air in area 38 is precisely of the same character as in areas 39 and 40, viz., from the eastward, while that in area 47 is of the same character as the movements in 48, 49, and 50; it is clear, therefore, that to the south of Lat. 30° S. we have generally an opposite stream of air to that immediately north of the same parallel.

The wind in avea No. 48 blows during the three months almost directly along and outwards from the land, and the same directions are preserved (nearly) in avea No. 49. In area No. 50 it is altered, the general winds being from N.N.W. to W.S.W., although the prevailing wind is towards N.N.W.

The winds in areas 58, 59, and 60 are very similar in their character to those in areas 48, 49, and 50, as will be seen below.

58. Area included between Lat. 40° and 50° §., Long. 30° and 40° KE,

Prevailing wind, W.S.W. Frequent winds, N.N.W. - W.N.W. - N.N.E. (476.) 59. Ayvea included between Lat. 40° and 50° S., Long. 40° and 50° E. Prevailing wind, W.S.W. and W.N.W. Frequent winds, N.N.W. (475.) 60. Area included between Lat. 40° and 50° S., Long. 50° and 60° E, Prevailing wind, W.N.W. Frequent winds, W.8.W - N.N.W. (474.) - The wind in areas 566,574,574, is part of the same N.W-ly stream of air. 564. Area included between Lat. 40° and 45° S. anit. 15° and 20° B. Prevailing wind, N.N.W. Frequent winds, 8.W. - W.S.W. - W. - W.N.W, (478.)

57a. Area included between Lat. 40° and 45° 8., Long. 20° and:25° XK. Prevailing wind, W. Frequent winds, S.SSW. - W.N.W. - N.N.W. (447.)

576, Area included between Lat. 40° and 45° S., Long. 25° and 30° KE. Prevailing wind, W.S.W. Frequent winds, W.N.W., N.N.E., and N.N.W. (477.) The last two are,

however, far less common than the prevalent W.S.W. to W.N.W. winds,

The South Hast Trade.

The only instances of the 8.E, Trade during the three months occur in «reas 24 and 32. In the first (or northern) of these aveas the prevalent wind is S,3 in the southern it is 8,E,

32 WINDS OF THE SOUTH INDIAN OCEAN.

24. Area included between Lat. 0° and 10° 8., Long. 50° and 60° E. Prevailing wind, S. Frequent winds, S.E. - S.W. - W. - N.E (330.)

325, Area included between Lat. 10° and 15° S., Long. 55° and 60° E. Prevailing wind, 8.E. (366.)

32d, Area included between Lat. 15° and 20° S., Long. 55° and 60° E, Prevailing wind, S.E. Frequent wind, E. (366.)

In area 23 the S.E. Trade shows itself, but is overpowered by other streams of

air.

Cart Dracram No. I., January, February, March. (The Southern Summer.)

The stream of air sweeping the coast of Africa : -

46), Area included between Lat. 30° and 35° S., Long. 15° and 20° E.

Prevailing winds, 8.S.E, and 8.8.W.

Frequent winds, E.S.E. - S.E. - S, (442.) The general direction of the wind in this avea is scarcely altered during these three months as compared with its direction during October, November, and December, (see same area on p, 29,) it is now perhaps more parallel with the coast than blowing towards the land. The same kind of owt-blow mentioned on p. 28 is however apparent.

46d, Area included between Lat, 35° and 40° S., Long. 15° and 20° E.

Prevailing wind, E.S,E.

Frequent winds, 8.8.E. - S.E. - S.8.W- - W.S.W. - W.N.W. (442.) As regards this area, it is not a little remarkable that while the prevailing wind during January, February, and March is exactly the opposite of that during October, November, and December, the frequent winds should be nearly the same; the legitimate conclusion is that the same winds prevail between Lat. 35° and 40° S. and Long. 15° and 20° E. during the summer six months of the southern hemisphere. The area is one that is sailed over by many ships proceeding to Australia, and by nearly all bound to India and China; it will be seen that the wind mostly blows towards the African continent.

47. Area included between Lat. 30° and 40° S., Long. 20° and 30° E,

Prevailing wind, W.S.W.

Frequent winds, E.N.E, - E.S.E. - S.S.E, - S.S8.W. - W.N.W. - N.N.E. (441.) Of these winds the E.N.E.,8.8.E., and W.N.W., are more frequent than the other three, so that the wind-star in the chart of the Board of Trade presents a very flattened appearance, being drawn out in its greatest length towards E.N.E. and W.S.W. But there is evidence that at this season of the year, there is a considerable tendency towards Hasterly winds.

38d, Area included between Lat. 25° and 30° S., Long. 35° and 40° B.

Prevailing wind, S.S.E.

Frequent winds, 8S\ - E.8.E. - E.N.E. (404.) The character of a system of on-shore winds is maintained in this area during the southern summer,

38c, Area included between Lat. 25° and 30° S., Long. 30° and 35° FE. Prevailing wind, 8.S.W. Frequent winds, §. - S.S.E. - E.S.E. - E.N.E. - N.N.E. (404.) In this . #red, during the summer, winds along-shore are prevalent.

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38). Aveaincluded between Lat. 20° and 25° S., Long. 35° and 40° E. Prevailing wind, S. Frequent winds, S.E. - S.S.E. (404.) The tendency of the winds in this area during the summer is towards the rarefying surface northward of the Mozambique Channel.

The so-called North-East Monsoon : - 31. Area included between Lat. 10° and 20°8., Long, 40° and 50° E Prevailing wind, N.N.W. Frequent winds, N.W. - W.N.W. - S.S.W. - S.S.E. - ES. B. - E.N.E. - N.N.E. (367.)

As in the spring months, so in the summer months of the Southern Hemisphere, the winds in the northern part of the Mozambique Channel are subject to very con- siderable variations. The frequent winds indicate that three systems alternate here : (1) that of the wind sweeping along the coast; (2) that of the N.E. monsoon; and (3) that of the wind towards the interior of Madagascar - of which the prevailing wind of the aveais a component part. In addition, it must be borne in mind that calms are very frequent at this period.

23. Area included between Lat. 0° and 10° S., Long. 40° and 50° E.

Prevailing wind, N.N.E.

Frequent winds, E.S.E. - E.N.E. - N.E. - N. - N.W. (331.) 22d. Area included between Lat. 5° and 10° S., Long. 35° and 40° EF.

Prevailing wind, N.E. (332.)

The winds of the above areas (31, 23, and 22d) are those of the Monsoon, many of them being evidently part of the N.W. Monsoon winds prevalent at this season south of the Equator; but whether any characteristic wind marks the Mozambique Channel during the summer is very doubtful.

Easterly Winds North of Lat. 40° 8. :

32d. Area included between Lat. 10° and 15° S., Long. 55° and 60° E. Prevailing wind, E. Frequent winds, N.E. - N. (366.)

32d, Area included between Lat. 15° and 20° S., Long. 55° and 60° E,

Prevailing wind, E.

Frequent winds, E.8.E, - E.N.E. - N.E. (366.)

40. Area included between Lat. 20° and 30° S., Long. 50° and 60° E.

Prevailing wind, E.N.E.

Frequent winds, E.S.E. - E. - S.E. - S.8.E. (402.)

39. Area included between Lat. 20° and 30° S., Long. 40° and 50° E.

Prevailing wind, E.S.E.

Frequent winds, 8.S.E. - E. - E.N.E. - N.E. - N.N.E. (403.)

Similar remarks to those made on the spring wind (October, November, Decem- ber) will apply to January, February, and March, for areas 40 and 39. 48. Area included between Lat. 30° and 40° 8., Long. 30° and 40° E.

Prevailing wind, E.N.E.

Frequent winds, N.N.E. - E.S.E. - S8.S.E. - 5S.8.W. - W.S.W. (440.) During the summer months (Januar Z February, aaah the general blow of the winds in this area is nearly the opposite to that which is recorded for

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WINDS OF THE SOUTH INDIAN OCEAN.

October, November, and December. On page 31 it is noticed that in area No. 48 the winds blow outwards from the land during the spring months. In the summer they blow inwards, towards and along the coast of Africa; in fact there are two distinct systems traceable - that along the African coast, and a general stream from the eastward, gradually becoming north-easterly.

49, Area included between Lat. 30° and 40° S., Long. 40° and 50° E.

Prevailing winds, N.N.E. and 8.8.W.

Frequent winds, E.S.E. - E.N.E. - S.S.E. - W.S.W. - N.N.W. - W.N.W. (439.) The numerous arrows inscribed on this avea are sufficient to show that the locality is subject to great variations in the direction of the wind during the three summer months. 'There is, however, a preponderance towards the African coast, and this combined with one of the prevalent winds coming from N.N.E., will enable us to include it in the stream of air shortly to be noticed blowing in a somewhat contrary direction to that sweeping along the coast. On the whole, the winds in this area during the southern summer are very variable, and of all the aveas between Lat. 0° and 50° §., Long. 10° and 60° E., this is the most likely one in which vessels either outward or home- ward bound may fall in with head winds during the three months : - If pro- ceeding towards the Mauritius, a head wind may be experienced from E.N.E. or thereabouts; if coming eastward round the Cape, the head wind may be W.S.W.; the chances are, that the wind may spring up from almost any of the other six points recorded above as frequent winds, but with no degree of certainty from either N.N.E. or S.S.W. It may be regarded, therefore, as a tedious area to sail across, owing possibly to this fact, that when the sun takes up his position over the southern tropic, the heated water (alluded to on page 27) advances towards the south, giving an almost entirely new direction to the winds of areas Nos. 49 and 48, and creating streams of air the tendency of which is to oppose one another. It would, however, be better to trim the ship to sail on the best course compatible with the general sweep of wind, which we now proceed to notice.

Westerly Winds South of Lat. 40° S.: -

566. Area included between Lat. 40° and 45° 8., Long. 15° and 20° E.

Prevailing wind, W.S.W. Frequent winds, W.N.W. - N.N.W. (478.)

57. Area included between Lat. 40° and 50° S., Long. 20° and 30° BE,

Prevailing wind, W.N.W. Frequent winds,S.8.W. - W.S.W. - N.N.W. - N. - N.N.E. - E.N.E.(477.)

58. Area included between Lat. 40° and 50° §., Long. 30° and 40° EB.

Prevailing wind, W.S.W. Frequent winds, 8.8.W. - W.N.W. - N.N.W. - N.N.E. (476.)

59. Area included between Lat. 40° and 50° 8., Long. 40° and 50° E,

Prevailing wind, W.S.W. Frequent winds, W.N.W. - N.N.W. Occasionally, N.N.E. (475.)

60. Area included between Lat. 40° and 50° 8., Long. 50° and 60° E.

Prevailing wind, N.N.W. Frequent winds, W.8.W. - W.N.W, (474.)

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The general direction of the wind in the above five areas is from W.N.W. to W.S.W., in comparison with which scarcely any winds are experienced from the eastern horizon. The only well-marked instance of a series of winds opposite to those from W.N.W. - viz. E.8.E,. - is found in area 48; the phenomena are, how- ever, incompatible with the notion of a descending current, resulting from opposite streams of air.

In area 50 there is a somewhat similar play of winds to that in avea 49, and the well-marked distinction between an easterly and westerly movement at this season probably commences in the former area, or perhaps it would be better to regard areas 50 and 49 as of an intermediate character, separating the easterly current to the north, and the westerly current to the south. The winds are as under,

50. Area included between Lat. 30° and 40° §., Long. 50° and 60° E.

Prevailing wind, N.N.W.

Frequent winds, partaking of the westerly arden W.N.W. - W.S.W, - S.S.W.

Frequent winds, partaking of the easterly movement, 8.8.E. - E.S,E. - E.N.E. - N.N.E. (438.)

It will be observed that the prevalent winds of aveas 50 and 60 are identical, - they would indicate that, in addition to the two streams above alluded to, a stream of air towards S.S.H. existed in these aveas during the three months: indeed, refer- ring to CHart Dracram No. I., area 50, it appears that, more or less, during the southern summer, the wind has a tendency to blow in this direction.

The N.W. Monsoon: - There is only one more area to notice, - 24, Lat. 0° to 10° S., Long, 50° to 60° E., the prevalent wind of which is N.W., - the remaining winds bear but a small proportion to this, which is the characteristic wind of the region.

Allusion is made to the change in the direction of the wind that is effected over the area embraced by that part of the Coart Dracrams during the winter season of the southern hemisphere, as compared with the summer, more especially as regards the establishment of the S.E. Trade, embracing the western portion of the Southern Indian Ocean to the Equator, - and also the remarkable influence which is exerted on the so-called N.W. passage winds to the south-eastward of the Cape of food Hope, particularly during the months of July, August, and September.

Cuart Diacram No. III., April, May, June. (The Southern Autumn.)

Winds along the Southern and Eastern Coasts of Africa : -

The augmentation of the number of areas in which this coasting wind is found, during the months of April, May, and June, shows most distinctly that not only is its prevalence ¢ncreased, but it extends much farther from the shore than at other seasons. It is during the southern autumn, therefore, that the mariner may expect to find this particular wind not only sweeping over a greater extent of surface, but most probably blowing with greater strength.

46). Area included between Lat. 30° and 35° 8., Long. 15° and 20° KE,

Prevailing wind, E.S.E. (442.)

Other winds, chiefly between 8.8.E. and W.N.W., may be expected, but are insignificant as compared with the E.S.E. wind, which blows outward from the land,

D2

36

WINDS OF THE SOUTH INDIAN OCEAN.

46d, Area included between Lat. 35° and 40° 8., Long. 15° and 20° E.

Prevailing winds, $.S.W. and W.S.W.

Frequent winds, N.N.E. - E.S.E. - 8.E.- - 8.S.E.--S. - S.8.W. - S.W. - W.S.W. - W. - W.N.W. (442.) Although the winds in this area are so numerous, yet the prevailing direction is towards the Cape; from the great spread of the wind in this area it is not at all unlikely that a stream sets from the southward towards the Cape, and that, as it approaches the land, it is divided into two branches, one passing outwards toward the N.W., the other outwards toward the N.E.; this kind of movement is shown on the Cuart Dracray, and itis more or less established from January to June in- clusive (¢.e. during the summer and autumn months), while the sun is rece- ding from the southern tropic.

In anticipation of any remarks to be offered on this avea, when treating of CHart

Diagram No.LV., it may be here observed, that during the months of July, August, and September, the direction of the wind in avea 46d is so altered, as to blow rather along than towards the land. This fact is worthy of notice, because it may be seen by reference to the four CnHart Dracrams that during nine months of the year - between Lat. 35° and 40°S., Long. 15° and 20° E. - the wind blows almost directly towards the southern extremity of the African continent ; but before it arrives there, it diverges into two well-marked streams - one towards W.N.W. or N.W., the other towards E.S.E., while there is also, from October to June, a general tendency of the wind towards the land.

57a. Area included between Lat. 40° and 45° S., Long. 20° and 25 E,

Prevailing wind, W.S.W. Frequent winds, 8.8S.W. - E.N.E. (477.)

57b. Area included between Lat. 40° and 45° 8., Long. 25° and 30° E.

Prevailing wind, W. Frequent winds, W.S.W. - E.N.E. - N.N.E. - W.N.W.

58a. Area included between Lat. 40° and 45 S., Long. 30° and 35° E.

Prevailing wind, S.W. Frequent winds, W.S.W. - W. - N.N.E. (476.)

47, Area included between Lat. 30° and 40° 8., Long. 20° and 30° E.

Prevailing wind, W.N.W. ; Frequent winds, W.S.W. - W. - S.8.W. - N.N.E. (441.) The direction of

- the prevailing wind is that of the general sweep of the so-called N.W. passage

winds, while the directions of the frequent winds are more or less in accordance with the sweep round the African coast. The N.N.E. stream is also obser- vable ; - there are more calms met with in this than in the neighbouring areas.

The sun is now north of the Equator, and the general stream of air is from the

westward, although easterly winds are sufficiently conspicuous to be embarrassing to vessels running down their easting.

48, Area included between Lat. 30° and 40° 8., Long. 30° and 40° EK.

Prevailing wind, S.S8.W.

Frequent winds, S. - S.W. - W.N.W. - N.N.W. - N. - N.N.E. - N.E. - E.N.E. - E.S.E. - S8.8.E. (440.) The direction of the wind in this area is very variable, more especially from January to June. It has already been remarked that the general direction is reversed in January, February and March, as compared with October, November and December - being

49,

39.

WINDS OF THE SOUTH INDIAN OCEAN. 37

Srom the land during the latter period, and ¢o it during the former. In April, May and June, the wind ean hardly be said to blow either to or from the land, being somewhat similar in form to that of area No. 47. The prevailing wind is from §$.8.W., the next in length of duration is exactly opposite, viz., from N.N.E., and the third, from E.N.E. It is clear, therefore, that at least two streams of air prevail here at this season, - that from §.8.W. being part of the African along-shore wind, while that from N.N.H. and E.N.E. (tending towards the south) is more strikingly developed in July, August and Sep- tember, although indications of it exist all the year round. The general westerly current is perceptible in the wind from W.N.W.

Area included between Lat. 30° and 40° S., Long. 40° and 50° E.

Prevailing wind, 8.S.W.

Frequent winds, N.N.E. - W.N.W. - S.8.E. - S.W. - W.S.W. - W. - N.W. - N.N.W. - N. - N.E. - S. (439.) This area during the three months partakes of precisely the same character as area 48. The winds are subject to considerable variations, but generally prevalent between S.S.W. and N.N.E., round by west.

Area included between Lat. 20° and 30° S., Long. 40° and 50° E.

Prevailing winds, §.S.E. - E.S.E.

Frequent winds, S.S.W. - S. - S.E. - E. - E.N.E. (403.)

. Area included between Lat. 20° and 30° S., Long. 30° and 40° E.

Prevailing wind, 8.

Frequent winds, 8.8.W. - S.S8.E. - 8.E. - E.S.E. - E. - E.N.E. - N.N.W. (404.) The merging of the African along-shore wind into the §.E. Trade is so apparent in areas 39, 38, that no further remarks are required, and the remaining areas will be described in connexion with that Trade-wind.

Lhe South-East Trade- Wind : -

During the three months of April, May and June, the S.E. Trade sweeps over the whole of the northern part of the Southern Indian Ocean, 2.e. from the parallel of 28° 8S. to the Equator. In the region under discussion (viz., the westernmost portion of the Indian Ocean) the 8.E. Trade has this peculiar modification, - it blows from S.E. to §., with a tendency near the Equator to merge into the S.W.

Monsoon.

In all the areas bounded by the Equator and Lat. 20° S., Long. 35° and 60° E., the prevailing wind is either S.E. or 8.S.E. 40. Area included between Lat. 20° and 30°S., Long. 50° and 60° E.

Prevailing wind, E.S.E. Frequent wind, E.N.E. - E. (402.)

32d. Area included between Lat. 15° and 20° S., Long. 55° and 60° E.

Prevailing wind, E. Frequent winds, E.S.E. - S.E. - S.S.E. - S.W. - S. (366.)

32b. Area included between Lat. 10° and 15° S., Long. 55° and 60° E.

Prevailing wind, S.E. Frequent winds, E. - E.S.E. (366.)

32a. Area included between Lat. 10° and 15° S., Long. 50° and 55° E.

Prevailing wind, 8.E. Frequent wind, 8.S.E.

38 WINDS OF THE SOUTH INDIAN OCEAN.

316. Area included between Lat. 10° and 15° 8., Long. 45° and 50° E. Prevailing wind, S.E. Frequent winds, 8.S.E. - S. - S.8.W. (867.)

30d, d3le, 3la, 22d. Areas included between Lat. 5° and 20° §., Long. 35° and 45° E. Prevailing wind, 8.S.E. Frequent winds, 8. and 8.E.

24. Area included between Lat. 0° and 10° S., Long. 50° and 60° E. Prevailing wind, S.E. Frequent winds, 8. - S8.8.E. (330.)

23. Area included between Lat. 0° and 10° S., Long. 40° and 50° E. Prevailing wind, 8.H. Frequent winds, S. - S.S.E. - E.S.E. (331.)

The easterly winds between Lat. 20° and 40° S., which were so conspicuous during January, February, and March, are only to be recognised as mere frequent or occasional winds in April, May, and June, and by no means as prevalent ones.

The westerly winds south of Lat, 30° S. ave only predominant in areas 50, 59, and 60.

50. Area included between Lat. 30° and 40° S8., Long. 50° and 60° E.

Prevailing wind, W.N.W. Frequent winds, N.N.E. - N. - N.N.W. - N.W. - E.S.E. - S.8.E. - S. - S.8S.W. - W.S.W. (438.) 59, Area included between Lat. 40° and 50° 8., Long. 40° and 50° E. Prevailing wind, W.S.W. Frequent winds, 8.8.W. - W.N.W. - N.N.W. - N.N.E. (475.) 60. Area included between Lat. 40° and 50° 8., Long. 50° and 60° E. Prevailing wind, W.S.W. Frequent winds, 8.8S.W. - W. - W.N.W. - N.W. - N.N.W. (474.)

Cuart Diagram No, IV., July, August, September. (The Sowthern Winter.)

The winds at this season admit of the same four-fold arrangement as in CHART Diacram No. II., viz., the winds along the African shore, - the S.H. Trade, the easterly stream, - and the westerly winds forming the so-called N.W. passage winds. Of these; the first three are most strikingly developed, but the last is not so promi- nent in this part of the Indian Ocean as might be expected.

Winds along the Southern and Eastern Coasts of Africa : -

46). Area included between Lat. 30° and 35° S., Long. 15° and 20° K, Prevailing wind, H.S.E. Frequent winds, S.E. - S.5.E. - S.S8.W. - W.S.W. - W.N.W. (442.)

Upon comparing these frequent winds with others in the same area at the various seasons, we find that during the three months, July, August and September, the wind blows more fowards the land, or from the S. and W., than at the other periods of the year. The following table will place this in a clear light, and show at a glance the winds that may be expected at any season in making the Cape.

o 510

Lonpon, James Imray & Son.

RR ee

2g

SS aes

|

|

i H t {

| | | |

WINDS OF THE SOUTH INDIAN OCEAN.

_ Seasons armen Rabi vated Spring. | Summer. | Autumn. | Winter | Prevailing winds,,., 8.S.E S.S.E. E.S.E. E.S.E MOREA cil: Sp A de onli cncreg Hie abe EA REL 'Frequent winds .... ESE. | ESE, a ee | SH S.E. a S.E. | Fa seal ak bcos ami % | S.S.E. ,OBSBIWe | PELE = Po see es | bes wakechertie Dash ttc 4 | WS.W, | acs tincdesen Packer ORS 5 | W.N.W.

46d. Area included between Lat. 35° and 40°S., Long. 15° and 20° E. Prevailing wind, W.N.W. Frequent wind, W.S.W. (442.)

The arrangement of the wind in the two areas Nos. 460, 46d, for July, August, aud September, is somewhat similar to that for October, November, and December, see CHART Dracram No, I. and p. 29; thus it would appear that during the six months from July to December, inclusive, the same meteorological forces are in operation in the neighbourhood of the Cape. The collected results are as under : - ~

MONON B is basin crads Spring. | Summer. | Autumn. 3 Winter no dpe. Ee Ee EE Td ee |

Prevailing winds .... W.N.W. | ES.E S.9.W. | W.N.W. | rang oy ee einer ce W.S.We | seeeeeene |

Frequent winds...... S.S.E. S.S.E. S.S.E | nee SS. VV) aero. VV. S.S.W | gett |

W.S.W. WOT cl ebyamaly at Reatl cool) «1

NVI: i Weteas aps ti

eeeoereoe

The prevailing wind of winter and spring appears only as a subordinate wind in the summer and autumn. The similarity between the winds of winter and spring is very apparent, also the difference that exists between these seasons and summer.

566. Area included between Lat. 40° and 45° §., Long. 15° and 20° E.

Prevailing wind, W.N.W. Frequent winds, 8.E. - S.W. - W.S.W. - W. - N.N.W. (478.)

This avea has been considered previously under the head of " Westerly winds." In consequence however of the great northerly stream of air, shortly to be noticed, it must now be considered as a part of the wind sweeping along the African Coast. The following Table shows the changes the wind undergoes here at different seasons : -

NOABUMEIs site cues: «<: | Spring Prevailing winds " N.N.W Frequent winds,,.... Baars oe, S.W. W.S.W W. W.N.W

Summer.

W.S.W.

- - -

re

re ee

| Autumn. Winter. | W.S.W. | W.NLW. | ft Ais. S S.E, Wax iih S.W. | W.N.W. W.S.W. ibrsiasiy pa onan ebay gare N.N.W

40 WINDS OF THE SOUTH INDIAN OCEAN.

47. Area included between Lat. 30° and 40° S., Long. 20° and 30° E,

Prevailing winds, W.S.W. - W.N.W. Frequent winds, S.S.W. - S.W. - W. - N.N.W. - N.N.E. (441.)

The wind-stars of this avea, in the Board of Trade Charts, from April to De- cember, inclusive, present a somewhat similar appearance to each other, which is greatly in contrast with the flattened wind-star of January, February, and March. The area is an important one, as both our outward and homeward-bound vessels generally pass through it. The following Table exhibits the variations of wind (at different seasons) that take place within its boundaries : -

WOASONS sarees. renee ss Winter. Spring. | Summer, | Autumn. | Prevailing winds WESSW eee WAS team cor ky W.N.W HSV IN WY 5) ce meer isatat! wipes as etme epest keene Frequent winds...... (picks S.8.W Scary. 8.5. W. iarsacsra) sien a ies cee eens Beings 7 Ciera 5 sae E.S.E Sa oe Bstavcnteres eee en re EINGEs2 Haye eda ANE E od pee rerer renee Saree 2 CREO my, NIN CVn) ae wnchanaay oa A pecc cae ve merce eee te W.N.W. | W.N.W staitaect Vite: Macon) aocwtat eg Me us ccies ae W. courbes WOR Sc Me aes W.S.W | SW. | senteeees | ceenen eee fh nertee ees

38. Area included between Lat. 20° and 30° §., Long. 30° and 40° E. Prevailing wind, 8. Frequent winds, S.8.W. - S.S.E. - S.E Le S.E. - E. - E.N.E N.N.E. - N.N.W. (404.) It will be seen on consulting the CHart Diacram, that the along-shore winds merge into the S.E. Trade as is the case during April, May, and June (see p. 37).

The South-East Trade : -

The areas on our diagrams over which the S.E. Trade sweeps during the winter of the southern hemisphere, are nearly the same as those over which it sweeps during the autumn, viz. Nos. 22, 23, 24, 31, 32, and 40. In these areas, with the excep- tion of Nos. 31 and 40, the prevailing wind is §.E., in 31 itis S.S.E., and in 40 E.S.E.; the commander may therefore fully reckon upon S.E. breezes (as is well known) dann July, August and September, between the Equator and Lat, 20° S., Long. 35° and 60° E., also between Lat. 20° and 30° S., Long. 50° and 60° E this, however, forms but a small part of the S.E. Trade that sweeps over the aan Ocean. No further remarks are necessary on the areas above mentioned.

E. - N.E. -

Easterly Winds between Lat. 20° and 30° Noe

These winds scarcely show during the winter season of the southern hemisphere. The easterly stream of air so well marked between 20° and 30° S. Lat. in the Indian Ocean during April, May, and June, and to which we shall direct further attention, now only occurs asa very subordinate wind. The E.N.E. wind of avea 39 is the only well-marked remnant of this easterly wind, and an inspection of the CHART DraGram will show that it forms a portion of the stream to the southward, which

WINDS OF THE SOUTH INDIAN OCEAN. AL

was somewhat obscurely indicated during the autumn, and is now strongly developed and most decidedly well marked. 39. Area included between Lat. 20° and 30° S., Long. 40° and 50° H. Prevailing wind, E.N.E. Frequent winds, N.N.E. - N.E. - E. - E.S.E. - S.8.E. - S.S.W. (403.) During the months of April, May, and June, the winds in this area (39) certainly form a portion of the great S.E, stream of the Trades; now (July, August, and September) they appear to form a part of the great N.N.E. stream, that sweeps over the southern part of the ocean towards the south. The change the direction of the wind undergoes in the winter, as compared with the autumn, will be seen in the following arrangements : - Autumn......5.S.W. - S - S.S.E. - S8.E. - E.S.E. - E. - E.N.E. Winter...,,. S.S.W. - * - S.S.E. - * - E.S.E. - E - E.N.E - -N.E. - N.N.E.

which shows that the S.E. winds are less numerous, while the northerly winds become moreso. The asterisks indicate that the S. and S.E. winds have not been met with in winter to the same extent as in autumn.

The great Southerly Sweep of Winds, South of Africa : -

An inspection of Cuart Dracram No. IV., aveas Nos. 39, 48, 57a, 576, 58a, 586, 59a, 59, and 60a, shows that over these portions of the Indian Ocean, the wind is drawn by some powerful force towards the south. While the general body of the S.E. Trade tends towards the N.W., the general body of the air south of Madagascar and the Cape tends towards S.8.W. It is difficult in the present state of our geographical knowledge to point out the locality of such a force. It is not a little remarkable that this stream of air is moving southerly in the winter, and may perhaps receive its explanation in the large condensation that takes place in the Antarctic Regions at this season. Professor Dove has shown that the condensation of aqueous vapour raises the temperature, and Mr. Hopkins* insists that this raising of the temperature produces the most powerful winds. While, however, this is a very interesting subject for investigation, the great object we have to deal with now is the practical application of it to the wants of the seaman. We shall therefore simply analyse the facts as they stand before us.

Area No. 39, see above. - It will be remarked that a very decided change of wind has taken place in this area since the autumnal months of April, May and June; then the prevalent winds formed a portion of the S.E. Trade; now, the southern force acts, and it is likely this aveais situated in the most northern part of the great southerly stream.

48. Area included between Lat. 30° and 40° S., Long. 30° and 40° E.

Prevailing wind, N.N.E.

Frequent winds, N.N.W. - W.N.W. - W.S.W. - S.8.W. (440.) The pre- vailing wind above is exactly opposite to the prevailing wind of this area in April, May and June ; - and the wind blows much more from the land than at that season.

57a. Area included between Lat. 30° and 40°S., Long. 20° and 25° E.

Prevailing wind, N.N.E.

Frequent winds, E. - W.S.W. - W.N.W. (477.)

57b. Area included between Lat. 40° and 45° S., Long. 25° and 30° E.

* Hopkins, "On Winds and Rain."

42 WINDS OF THE MONSOON REGION

Prevailing wind, N.N.E. Frequent winds, E.S.E. - W.N.W. - S.S.W. (477.)

58a. Area included between Lat. 40° and 45°S., Long. 30° and 35° E. Prevailing wind, N.N.E. Frequent winds, E.N.E. - N.E. - N. - 8. - W.S.W. (476.)

58d. Area included between Lat. 40° and 45°S., Long. 35° and 40° E. Prevailing wind, N.N.E. Frequent winds, N. - W.N.W. (476.)

59a, Area included between Lat. 40° and 45° S., Long. 40° and 45° E. Prevailing winds, N.N.E. - N.N.W. Frequent winds, W.N.W. - W.S.W. (475.)

596. Area included between Lat. 40° and 45° 8., Long. 45° and 50° E. Prevailing wind, N.N.E. Frequent winds, N.N.W. - E.N.E. - W.S.W. (475.)

60a. Area included between Lat, 40° and 45° S., Long. 50° and 55° H. Prevailing wind, N.N.E. | Frequent winds, 8.8.W. - W.N.W. - N. (474.)

The Westerly Winds South of Lat. 30° S.: -

In consequence of the great southerly sweep just indicated, the aeas over which the westerly winds blow are greatly reduced in number ; it will be sufficient here to notice the prevalent and frequent winds of these areas.

49, Area included between Lat. 30° and 40° S., Long. 40° and 50° EK,

Prevailing wind, N.N.W. Frequent winds, N.N.E. - W.N.W. - W.S.W. - S.8.W. (439.)

50. Area included between Lat. 30° and 40°S., Long. 50° and 60° E.

Prevailing wind, W.N.W. Frequent winds, N.N.W. - W.S.W. - S.S.W. (438.) 60d. Area included between Lat. 40° and 45° S., Long. 55° and 60° E. Prevailing wind, W.N.W. Frequent winds, N.N.W. - N.W. - W.S.W. (474.)

" a9. It remains now to discuss, briefly, that part of the central and northern Indian Ocean over which the Monsoons are prevalent - Lat. 10° S. to 30° N., Long. 50° to 100° E,

Chart Dracram No. I., October, November, December.

The S.A. Trade is now the general wind between Lat. 30° 8. and 5° S.

A brief remark may here be made on a very interesting phenomenon that takes 'place in connexion with the streams of air, situated more or less in the neighbourhood of the Calms of Capricorn. It is the divergence of the S.E. and E. streams between 20° and 30° 8. into two well-defined branches, - the 8.E. into the branch flowing northward, past Madagascar, and along the African Coast to 10° N., where it becomes a S.W. wind - and the E. into the branch flowing southward, past the southern extremity of Madagascar as an E.N.E. wind, off the extremity of Africa as a N.N.E. wind, and finally becoming N.N.W. in areas 58 and 59. It would appear that it is the African Coast that turns the two streams aside, but under what circumstances and to what region of rarefaction is not quite clear.

IN THE INDIAN OCEAN. 43

The intimate connexion that subsists between the winds in the region bounded by the parallels of 10° 8. and 10° N., Long. 40° to 100° E., necessitates a xceboration of that part of the ocean from the more northerly areas.

Regions of Westerly and South- Westerly Winds : -

In areas 15, 16, 17, 18, 19, 23, 24, 25, 26, 27, and 28, there are several distinct systems of wind - the most marked being a Westerly stream directed towards the Indian Archipelago (see aveas 17,18, 19, 25, 26, 27, and 28). A N.Wly. stream of air is also directed towards the Equator, and approaches, at times, very close to the S.E. Trade, and occurs likewise in areas 15, 16, 17,18,and 19. AS.W. wind is not unfrequent in aveas 15, 16, 17,18, 19, 25,26, 27, and 28; and a N.E. windin areas 15, 16, 18, 19, 23, and 24. This is clearly the N.E. Monsoon, which penetrates as far as the parallel of Cape Corrientes during the southern spring.

15. Area included between Lat. 10° and 0° N., Long. 50° and 60° E.

Prevailing wind, N.E.

Frequent winds, 8.W. - W. - N.W. - N. (81.) The frequent S.W. wind is evidently the closing portion of the 8.W. Monsoon, and may be looked for mostly in October.

16. Area included between Lat. 10° and 0° N., Long. 60° and 70° E.

Prevailing wind, N.E.

Frequent winds, §8.W. - N.W. - N. (30.) The N.W. wind is much more prevalent in this avea than in No. 15.

17. Area included between Lat.'10° and 0° N., Long. 70° and 80° E.

Prevailing wind, N.W.

Frequent winds, 8.W. - W. - N.N.W. - N. (29.) It is in this area that the Westerly wind is first perceptible, north of the Equator. The N.E. Monsoon is scarcely experienced here; the 8.W. is also much subdued, - the prevailing wind being N.W., which blows more or less during the three months along the Malabar coast.

18, Area included between Lat. 10° and 0° N., Long. 80° and 90° EK,

Prevailing wind, W.

Frequent winds, §.W. - N.W. - N. - N.E.--E. (28.) Approaching the Indian Archipelago there is a much greater play of the winds.

19. Area included between Lat. 10° and 0° N., Long. 90° and 100° E.

Prevailing wind, W. Frequent winds, 8.W. - N.W. - N. - N.E. - E. - S.E. (27.) . Area included between Lat. 0° and 10° S., Long. 60° and 70° E. Prevailing wind, W. Frequent winds, 8. - H. - S.W. - N.W. - -E.S.E. (329.) Calms are frequent.

It is in this area, south of the Equator, proceeding from west to east, that

there is the earliest indications of the westerly stream towards the Indian

Archipelago.

26, Area included between Lat. 0° and 10° S., Long. 70° and 80° E. Prevailing wind, 8.W. Frequent winds, W. - W.N.W. - S.E. (328.) Of these frequent winds

that from the west is nearly as prevalent as the S.W. Calms are less frequent,

Ke Or

44. WINDS OF THE MONSOON REGION

27. Area included between Lat. 0° and 10° 8., Long. 80° and 90° E.

Prevailing winds, W. - S.E.

Frequent winds, S.W. - N.W. - E. (327.) In this avea the 8.E. Trade is quite as prevalent as the westerly wind, but it is characterized by the greatest number of calms that are met with between the Equator and 10° 8S. Lat.

28. Area included between Lat. 0° and 10° S., Long. 90° and 100° E.

Prevailing wind, 8.E.

Frequent winds, 8.S.E. - S. - S.W. - W. - N.W. - E. (326.)

The S.E. Trade is by far the most prevalent, then the streams from 8.8.E. and S.W.; with the exception of the easterly and westerly streams of air, the wind blows mostly from the South. Calms are very prevalent.

The North-East Monsoon: -

It will be seen that the N.E. Monsoon blows, at least during a portion of the three months (October, November, December), a N.E. wind from the northern parts of the Bay of Bengal and the Arabian Sea, towards the Equator. The Penin- sula of Hindostan separates the Northern Indian Ocean into two parts ; - in the eastern portion the Monsoon Jlows as far as the Equator. Between the Equator and 10° S. lies the region of calms - and here it is that a very remarkable arrangement of the winds obtains. The N.E. Monsoon north, and the 8.E. Trade south of the Equator, are similarly disposed to the N.E. and S.E. Trades of the Atlantic, which meet under the " Cloud-ring." While, however, we have the N.E. Monsoon thus blowing towards the Calm Belt, there is alsoa north-west wind meeting the 8.E. Trade in the same region. It is in the western portion of the Indian Ocean that the N.E. Monsoon crosses the Equator ; - it appears to blow steadily from the head of the Arabian Sea, not only in the open ocean, but along the coasts of Arabia and Africa, penetrating the Mozambique Channel as far as Cape Corrientes. It is only on the western shores of Hindostan that the N.E. Monsoon is interrupted by the N.W. wind. 1d. Area included between Lat. 25° and 20° N., Long. 55° and 60° E. Prevailing wind, E. Frequent winds, N.E. - S. - S.W. (103.)

2d. Area included between Lat. 25° and 20° N., Long. 65° and 70° E. Prevailing wind, N.E. (102.)

8. Area included between Lat, 20° and 10° N., Long. 50° and 60° E. Prevailing wind, N.E. Frequent winds, E. - 8.W. - W. (67.)

9, Area included between Lat. 20° and 10° N., Long. 60° and 70° E. Prevailing wind, N.E. Frequent wind, N.N.E. (66.)

10a. Area included between Lat. 20° and 15° N., Long. 70° and 75° HK. Prevailing wind, N.E. Frequent wind, N.W. (65.) The N.W. wind is well marked. 11. Area included between Lat. 20° and 10° N., Long. 80° and 90° H. Prevailing wind, N.E. Frequent wind, N.N.E. (64.)

12, Area included between Lat. 20° and 10° N., Long. 90° and 100° E. Prevailing wind, N.E.

Frequent winds, E. - N. (63.)

IN THE INDIAN OCEAN, 45

In this avea the wind blows from the land.

The N.W. Stream on the West of Hindostan : -

10a. See above.

10. Area included between Lat. 15° and 10° N., Long. 70° and 75° E Prevailing wind, N.W. Frequent wind, N. (65.)

10d. Area included between Lat. 15° and 10° N., Long. 75° and 80° E, Prevailing wind, N.W. Frequent wind, S. (65.)

Winds at the Head of the Arabian Sea : -

1b. Area included between Lat. 30° and 25° N., Long. 55° and 60° E. Prevailing winds, N.W. - E. - W. - S. Frequent winds, 8.8S.E. - S.W. (103.)

In this sub-area, during the three months, not only is there a very great play of winds, but frequent calms; itis generally in similar localities that we find such great diversities. It would appear to be very difficult to reduce these winds to any well-recognised rule, such as the Trades and Monsoons.

la. Area included between Lat, 30° and 25° N., Long. 50° and 55° E,

Prevailing wind, W. Frequent wind, N.W. (103.)

In this swb-avrea there is a N.W. wind nearly as prevalent as the W. wind; it does not, however, appear to form part of the stream sweeping the west coast of Hin- dostan, being separated from it by the N.E. Monsoon.

2c, Area included between Lat. 25° and 20° N., Long. 60° and 65° E,

Prevailing wind, N, Frequent winds, N.E. - W. (102.) The wind in this svb-avea appears to be a part of the N.E. Monsoon.

Winds at the Head of the Bay of Bengal :- - 4d, Area included between Lat. 25° and 20° N., Long. 85° and 90° E. Prevailing wind, N. Frequent wind, N.K. (100.) 5c. Area included between Lat. 25° and 20° N., Long. 90° and 95° E, Prevailing wind, N. Frequent winds, N.N.W. - N.W. (99.) The prevalent wind in areas 4d and de is North, which merges into the Monsoon, while the frequent winds blow along-shore.

Cuart Dracram No. IL, January, February, March,

The South-East Trade : -

During this quarter of the year the 8.E. Trade attains its maximum polar develop- ment, but it scarcely reaches 10° 8. except on the eastern side of the Indian Ocean, hence we may say it is fully developed over psc rata of latitude - viz., from 31° to 11° 8, It is found to the northward of 10° S., in aveas 26,27, and 28, but

46 WINDS OF THE MONSOON REGION

owing to the more general prevalence of a westerly current of air between the Equator and 10° S., it ranks only as a frequent wind.

Region of the N.W. Monsoon : -

Between the Equator and 10° or 11° S. the N.W. Monsoon is in full operation during Jan., Feb., and March ; - in areas 24 and 25 blowing from the N.W., but in areas 26, 27, and 28 having a more westerly direction.

25. Area included between Lat, 0° and 10° §., Long. 60° and 70° K.

Prevailing wind, N.W. Frequent winds, N. - N.N.W. Occasional wind, W. (329.) 26. Area included between Lat. 0° and 10° 8., Long. 70° and 80° E. Prevailing wind, W. Frequent winds, N. - N.N.W. - S.E. - S.W. - N.N.E. - N.W. - W.N.W. - N.E. - W.S.W. (328.) 27. Area included between Lat. 0° and 10° S., Long. 80° and 90° EK. Prevailing wind, W. ; | Frequent winds, N.W. - S.W. - W.S.W. - S.E. - W.N.W. - E. (327.) 28. Area included between Lat. 0° and 10° S., Long. 90° and 100° E. Prevailing wind, W. Frequent winds, N.W. - S.W. - S.E. - W.N.W. - E. - W.S.W. (326.)

Calms are of very frequent occurrence in areas 27 and 28.

Region of the N.E. Monsoon : -

The N.E. Monsoon, during January, February, and March, is prevalent over all the northern part of the Indian Ocean. 15. Area included between Lat. 0° and 10° N., Long. 50° and 60° E. Prevailing wind, N.E. Frequent winds, N.N.E. - N. (31.) 16. Area included between Lat. 0° and 10° N., Long. 60° and 70° E. Prevailing wind, N,E. Frequent winds, N.N.E. - N. - Occasional wind, N.W, (30.) 17. Area included between Lat. 0° and 10° N., Long. 70 and 80° E. Prevailing wind, N. Frequent winds, N.E. - N.N.E. - Occasional winds, N.W. - S.W. (29.) 18. Area included between Lat. 0° and 10° N., Long. 80° and 90° E. Prevailing wind, N.E. Frequent winds, N. - E. - N.N.E. - E.N.E. (28.) 19. Area included between Lat. 0° and 10° N., Long. 90° and 100° FR. Prevailing wind, N.E. Frequent winds, N.W. - E. - N. - S.W. - S.E. - W. - E.N.E. - N.N.E. - S. (27.) Calms are very common in this avea: from the relative size of the lines in the wind-star of the Board of 'Trade Wind Chart, the wind during the quarter is, more or less, all round the compass. 8. Area included between Lat. 10° and 20° N., Long. 50° and 60°-E. Prevailing wind, N.E. Frequent winds, E. - E.N.E. - N.N.E. - Occasional wind, 8.E. te ) 9d. Area included between Lat. 10° and 15° N., Long. 65° and 70° E

IN THE INDIAN OCEAN. 47

Prevailing wind, N. Frequent winds, N.E. - N.W. (66.) 11. Area included between Lat. 10° and 20° N., Long. 80° and 90° E. Prevailing wind, N.E. Frequent winds, E. - N. - E.N.E. - N.N.E, Occasional wind, 8.W. (64.) 12a. Area included between Lat. 15° and 20° N., Long. 90° and 95° E. Prevailing wind, W.S-W. Frequent winds, N. - W. - S.W. - N.W. Occasional wind, N.E. (63.) 12¢, Area included between Lat. 10° and 15° N., Long. 80° and 95° K, Prevailing wind, N. Frequent winds, N.E. - N.N.E. (63.) 4d, Area included between Lat. 20° and 25° N., Long. 85° and 90° E. Prevailing wind, N.E. Frequent winds, N. - N.N.E. - W. - S.W. - N.N.W. - S. (100.)

The N. and N.W. Streams of Air on the West of Hindostan : -

10a. Area included between Lat. 15° and 20° N., Long. 70° and 75° E. Prevailing wind, N. Frequent winds, N.W. - N.N.W. (65.)

- 10e, Area included between Lat. 10° and 15° N., Long. 70° and 75° E. Prevailing winds, W. - N.N.W. Frequent winds, N.E. - N. - N.W. (65.) Occasionally a 8.E. wind is experienced.

10d. Area included between Lat. 10° and 15° N., Long. 75° and 80° E. Prevailing wind, N.W. Frequent winds, N.N.W. - N. (65.)

Winds at the Head of the Arabian Sea : -

2c, Area included between Lat. 20° and 25° N., Long. 60° and 65° E. Prevailing wind, S.W. Frequent winds, W. - W.S.W. - S.S.W. - S.E. Occasional wind, N.W. (102.) Calms frequent..

2d. Area included between Lat. 20° and 25° N., Long. 65° and 70° E. Prevailing winds, N.W. - W.N.W. Frequent winds, W. - S.W. - S. (102.)

During the six months, April to September, the S.A. Zrade-wind reaches the Equator, being known as the S.#. Monsoon in its more northern portion, and thence gradually merging into the S.W. Monsoon. Calms are less frequent during this period than during the other six months, viz. from September to April.

CuHart Dracram No, III, April, May, June,

The South-West Monsoon : - 1d. Area included between Lat. 25° and 20° N., Long. 55° and 60° E. Prevailing wind, 8. (103.)

48 WINDS OF THE MONSOON REGION

2a. Area included between Lat. 25° and 20° N., Long. 60° and 65° E.

Prevailing wind, 8.W. (102.)

4d, Area included between Lat. 25° and 20° N., Long. 85° and 90° E.

Prevailing wind, 8.W.

Frequent wind, 8. (100.)

8. Area included between Lat. 20° and 10° N., Long. 50° and 60° E,

Prevailing wind, 8.W.

Frequent winds, 8.E. - S. - E. (67.) Calms frequent.

11, Area included between Lat. 20° and 10° S., Long. 80° and 90° E.

Prevailing wind, S.W.

Frequent winds, S. - S.S.W. (64.)

12a. Area included between Lat. 20° and 15° N., Long. 90° and 95° E.

Prevailing wind, S.W. (63.)

12c. Area included between Lat. 15° and 10° N., Long. 90° and 95° E,

Prevailing wind, S.W. (63.)

15, Area included between Lat. 10° N. and Equator, Long. 50° and 60° E.

Prevailing wind, 8.W.

Occasional winds from N.E. to N.W. (80.)

16. Area included between Lat. 10° N. and Equator, Long. 60° and 70° E.

Prevailing wind, W.

Frequent winds, W.N.W. - S.W. (30.) Calms frequent.

17. Area included between Lat. 10° N. and Equator, Long. 70° and 80° FR.

Prevailing wind, W.

Frequent winds between N.W. and 8.W. (29.) The winds in the two areas 16 and 17 seem to be connected with the north-westerly stream of air on the west side of the Indian peninsula.

18, Area included between Lat. 10° N. and Equator, Long. 80° and 90° E.

Prevailing wind, 8.W.

Frequent winds between W. and 8.

Occasional winds between S.E. and N.E, (28.)

19, Area included between Lat. 10° N. and Equator, Long. 90° and 100° FE.

Prevailing wind, S.W.

Frequent winds between W. and S.

Oceasional wind, S.E. (27.)

The N.W. and W. Winds on the West Side of Hindostan : -

9, Area included between Lat. 20° and 10° N., Long. 60° and 70° E. Prevailing wind, N.W. Frequent winds, Si - W.S.W. - S. ; occasionally N.E. (66.)

10a. Area included between Lat. 20° and 15° N., Long. 70° and 75° E, Prevailing wind, N.N.W. Frequent winds, S.W. - N.W. (65.)

10c. Area included between Lat. 15° and 10° N., Long. 70° and 75° E, Prevailing wind, W. Frequent winds between 8.W. and N. (65.)

10d, Area included between Lat. 15° and 10° N., Long. 75° and 80° E. Prevailing wind, N.W. Frequent winds between §8.W. and N, (65.)

WINDS OF THE MONSOON REGION.

CHart Dracram No. IV., July, August, September.

The S.W. Monsoon : - ~ 1d. Avea included between Lat. 25° and 20° N., Long. 55° and 60° E.

2c

Prevailing wind, N. irequent winds, S.E. - S.W. (103.) . Areaincluded between Lat. 25° and 20° N., Long. 60° and 65° E, Prevailing wind, 8.W. Frequent wind, W.S.W. (102.)

2d. Area included between Lat, 25° and 20° N., Long. 65° and 70° E.

Prevailing wind, W. (102.)

4d, Area included between Lat. 25° and 20° N., Long. 85° and 90° E.

Prevailing wind, S.W. (100.)

8). Area included between Lat. 20° and 15° N., Long. 55° and 60° E.

Se,

Prevailing wind, S.W. (67.) Area included between Lat. 15° and 10° N., Long. 50° and 55° E. Prevailing wind, S. Frequent winds, between S.W. and S.S.E. Occasional wind, N.E. (67.)

8d. Area included between Lat. 15° and 10° N., Long. 55° and 60° E,

9.

10

Prevailing wind, S.W. (67.)

Area included between Lat. 20° and 10° N., Long. 60° and 70° E, Prevailing wind, W. Frequent winds, S.W. - W.N.W. (66.)

a. Area included between Lat. 20° and 15° N., Long. 70° and 75° E. Prevailing wind, W. Frequent winds, W.N.W. - W.S.W. (63.)

10¢c. Area included between Lat. 15° and 10° N., Long. 70° and 75° E.

10

11

12a & c. Area included between Lat. 20° and 10° N., Long. 90° and 95° E.

15

16

17

18

Prevailing wind, N.W. Frequent winds, W.N.W. - W. (65.)

d, Avea included between Lat. 15° and 10° N., Long. 75° and 80° E. Prevailing wind, N.W. Frequent winds, S.E. - W. - S. (65.)

. Area included between Lat. 20° and 10 N., Long. 80° and 90° E, Prevailing wind, S.W. (64.)

49

Prevailing wind, S.W. (63.) In the northern part of this area the wind

is more westerly; in the southern part more southerly.

. Area included between Lat. 10° N. and Equat., Long. 50° and 60° E. Prevailing wind, 8.W. (381.)

. Area included between Lat. 10° N. and Equat., Long. 60° and 70° E. Prevailing wind, W. Frequent winds, §.W. - S. (30.)

. Area included between Lat. 10° N. and Equat., Long. 70° and 80° KE, Prevailing wind, N.W. Frequent winds, W.N.W. - W. - S.W. (29.)

. Area included between Lat. 10° N. and Equat., Long. 80° and 90° E.

E

50

nates, as well as the duration of each

WINDS OF THE MONSOON REGION,

Prevailing wind, S.W.

Frequent winds, between W, and 8. (28.) 19. Area included between Lat. 10° N. and Equat., Long. 90° and 100° E.

Prevailing wind, S.W.

Frequent winds, between W. and 8. (27.) The N.W. stream of air on the West Coast of Hindostan is still present (sce area 10); but now (July to September) it is not the prevailing wind to the same extent as in the previous quarter.

ee

These remarks (pp. 25-50) sufficiently explain Crart Dracrams Nos. 1, IT., IIT., and IV., of the winds ot the Indian Ocean.

es

28. MAURY on the Monsoons. - With the view of investigating certain monsoon-phenomena - when and where each wind (N.E. or 8. W.) begins and termi-

Maury examined his abstract logs, and from

11,697 observations made at sea, between the meridians of 80° and 85° K., and from Caleutta to the Equator, constructed the following table, illustrative of what he aptly terms the march of the Monsoons : -

MontTHus,

22° to 20° N.|20° to 15° N N.E.|S.W.|N.E.|S.W.

Days,|Days.| Days.| Days.

(ctobere 7..08....) 9 Gieeze 26 November ......... /au | 6| 28] 2 December ,........ | a7 |.0; 26) 1 January ...... ek | and 62 February ........., 22 | a2 | 43] 6 | March wiictaet 4 1.ae@] 9.) 25 Rowley: ite: BET os a 2/24| 2)22 WAV Wer ceeteteissaeh ey 26) 1 Se DUNG iit aw. pee YRSHeuL Tay Linh Ste en ted 2|24@ | 1) 27 August ..... i Ben Lj 2e September ........ 6 |1%)/ Liisa. Mean Days* ...... 81 173 104.157

15° to 10° N,

N.E.

Days.

Banps oF LATITUDE.

And, taking into consideration the causes of these winds, Maury says that} " the S.W. Monsoons commence at the north, and back down, or work their way towards the south. Thus they set in earlier at Calcutta than they do at Ceylon, and earlier at Ceylon than they do at the Equator. The average rate of travel, or backing down to the south, as seamen express it, is from 15 to 20 miles a day. It takes the S.W.

* These means for the duration of each wind are obtained as follows: for N.H.=9+114+27417

+114+6=81 days; for S.W.=11+18+24+264+284+24+28+ 14=173 days.

+ " Physical Geography of the Sea," 11th edition, revised, chap. vi. §§ 684-689,

} )

MontTHLy

| Mean. |

10° to 5°N, |5° N, to Eq. |

$.W.IN.ES.WIN.E|S.W. NESW.

Days,| Days, | Days.|Days. rapier A Days. |

10| 6/16| 4/14 & | 10° 2)10| 6] 5|14) 24) 6 lias |} 3/32/41) 22) 3 1{/20/ ljas} 3j20| : 3/22; 1/36} 2/46) 5

5/23 | 0|35] 2) a2] 8 | 21; 6/)/31 |, 4/14 | 4 | 17 29} lja3|} O;a9| 1/123 22} 1}2s| 0} 24 | 0 27 30| O|28| O|2a) 1/27 22; ljaa| O|as| 0 (23 23 | 0|26; 1 12 | 2 20

149/92 151/62 /156 90 155

WINDS OF THE MONSOON REGION. 51

Monsoon six or eight weeks to back down from the tropic of Cancer to the Equator." And again - 'As the vernal equinox approaches, the heat of the sun begins to play upon the steppes and deserts of Asia with power enough to rarefy the air, and cause an uprising sufficient to produce an indraught thitherward from the surrounding regions, The air that is now about to set off to the south as the N.H. Monsoon; is thus arrested, turned back, and drawn into the place of low-barometer as the S.W. Monsoon. 'These plains become daily more and more heated, the sun more and more powerful, and the ascending columns more and more active; the area of inrushing air, like a circle on the water, is widened, and thus the $S.W. Monsoons, backing down towards the Equator, drive the N.E. Monsoons from the land, replace them, and gradually extend themselves out to sea."

29. The Table on p. 50 establishes what has already been observed, the greater per- sistency of the S.W. Monsoon over the N.E., but it is to be regretted that Maury should have selected the western side of the Bay of Bengal as an illustration of his theory of the backing down of the wind, inasmuch as the Monsoons undergo a greater modifi- cation from the lay of the land on that side than in any other part of the N. Indian Ocean ; and again, during the change of the Monsoon the breezes there by night are from 8.W. to W., by day from 8. to E.; and these have evidently been confounded with the season of the 8.W. Monsoon.* That these winds do penetrate far into the land is certain, but that their direction is very considerably modified thereby is also evident from the following observation made at Dum-dun, near Calcutta : -

Approximate Direction of Wind in the Mean Months. | re Order of Frequency. Direction. |

October .,....... | N.W.; S.W.; N.E.; N.; W.; S.E.; 8.; E.| N. 46° W. November ...... N.W.; N.; N.E.; W. N. 19° W. December ......, N.W.; N.; N.E.; W. N. 25° W. January ......... N.W.; N.; N.E.; W.; S.W.; E.; 8.E. N, 238° W. February ......| N.W.; W.; E.; N.E.; S.W.; N.; S.H.; 8.| N. 37° W. Baron hs vee ss S.W.; 8.; S.E.; W.; E.; N.E.; N.W. S10 Ww RMR pire cat S.; S.W.; S.E.; W. S. 17° W. OS Rane Bere S.; S.E.; S.W.; E. 8. 127.4, PUNO ves hua S.W.; E.; S.; S.E. Be. 11" KE: JUG cei S.E.; S.W.; S.; E.; W. S. - 12° B. August; 7208 -. S.W.; E.; S.H.; S.; W.; N.E. S. 25° E. September ...... S.E.; S.W.; E.; N.E.;.S.; W. SA BR

Tn the winter months there appears to be a marked predominance of N.W. winds ; so that in December the mean direction is N.N.W.: this predominance gradually 'diminishes, and in March the winds blow more frequently from the south than from the north, - the west winds still retaining their superiority over those from the east : this relation ceases, in its turn, in proportion as the meridian altitude of the sun in- creases ; and at the summer solstice the wind blows from the 8.S.E., a direction dia-

* That uncertainty as to the season does prevail is evident from the following remarks, extracted from HORSBURGH : - .

(Madras). 'During the 8.W. Monsoon, particularly in the early part of it, after the 1st of February," &c.

(Hoogly). '' When the southerly winds begin to have strength, during the latter part of March, or early in April," &c. &c.* " North-westers are liable to happen near the entrance and in the river Hoogly about the changes of the Monsoon, particularly in April and May," &e. &e,

E2

52 WINDS OF THE MONSOON REGION.

metrically opposite to that of the winter. The winds turn to the west when the decli- nation of the sun is more southerly; and in winter they settle, without variation, in the west. It will not fail to be observed that, generally, the winds are far too variable at the head of the Bay of Bengal to indicate when either Monsoon commences, - though the two seasons, in the main, are sufficiently well marked.

The influence of the declination of the sun upon the Monsoons has long been recog- nised on the west coast of Hindostan; as the sun arrives later at the zenith of places situated more northerly, so the 8.W. wind also blows later at these places: at Anjenga, in Lat. 83° N., it commences as early as the middle of April; at Bombay, in Lat. 19° N., not until the middle of May.* On the coast of Aracan it is not recognised to com- mence earlier than May. Such being the case, itis difficult to see how this Monsoon can back down on the east coast of Hindostan, and yet more difficult to understand the influence of the 'steppes and deserts" at the back of the Himalaya range (see p. 51), for these, together with the desert region behind the Hindoo Koosh, should, on MAuRyY's supposition, be more potential for Bombay than for Calcutta. Nor, if Maury is correct, could the 8.W. Monsoon be any longer regarded as the prolongation of the S.E. wind of theS. tropic into the N. tropic, as the N.W. wind is the prolongation of the N.E. from the N. to theS. tropic. The heated land unquestionably has an influence, but the sun must heat the tropical land bounding the Northern Indian Ocean before its effect can be felt on steppes and deserts in extra-tropical regions. There appears then no reason to alter the opinion already formed (pp. 18,19) on the production of the Monsoons.

30. As showing the predominance of the S.W. Monsoon over the N.E., as wellas the great variableness of the latter, the following Table, deduced from Mavry's charts, and the direction of the wind determined on the formule of Lampert, will be both useful and interesting to the navigator : -

| Nortnu LAtitvupe. S. LATITUDE.

| MonrHs. \25° to 20° 20° to 15° ee | ne'

15° to 10° 10° to 5° 5° t0. 0° | 0° ta 5° 15° to 10°

October...| ESE. | N.E. | SSE.) SW. | WS.w.] Ss. | ESE. November .) N.N.W.| N.N.E.| NE. | NE. | W.s.w./ W.S.W.| NINE. |

December .| N.N.E.| N.N.E.| NE. | ENE. NNW.| OW. W. January ..| N.E. N.E. N.E. N.E. | N.N.E. We S

February. .| W.N.W.| W.S.W.| N.E. | N.E. | N.NLE. | W.N.W.| S.W. | | March ...| W.S.W.| N.N.E.| N.E. | N.E. | NUE. | W.N.W.! S.W. | April... .| S.S.W. SSW.| S| SSE] 8.W. |winew.! s.w.

May ....| 8.8.W.|SS.W.|S8.W./ SW. | Sw. | sw] SE |

| | |

MEME oie 4, Viral u taewee S.W. S.W. S.W. S.S.E. S.E. GUVs vii cn) Des | ot, Wer enema Ent, WV .: || 9.5. We) S.Seiie tl Eee Be | August...) SS.W. | S.W. Sys We) 8. VV. S. S.E.

September.) S.S.W. S.S.W.| SW. | SW. | SW. |] SE. _ ESE.

* CAPPER, " On Winds and Monsoons." See also HorspurGu: "The S.W. Monsoon (on the western side of Hindostan) sets in earlier on the southern part of the coast than at Bombay, the difference in time being frequently fifteen or twenty days between Cape Comorin and that island." * * * " Between Cape Comorin and Anjenga the S.W. Monsoon or stormy weather from the S.W. may be expected to commence between the 20th and 28th of May, between Mount Dilly and (ioa early in June, and at Bombay from the 6th to the 15th of June."

= 5 ee

- «* \ *

. -

& nidanthre

BY C.MELORUM ESQ®

. : , en Stoo - - = - - - S===== 2 LonDon, James Imray & Son.

THE INDIAN OCEAN. 5

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F,

31. This general review of the winds of the Indian Ocean may be aptly closed with an extensive abstract from Mr. Metprum's* excellent paper - A Meteorolo- gical Journal of the Indian Ocean, roR Marcu, 1853, WITH A SUMMARY OF THE RusuLTs oF THE OssmRvATIons." It is based on observations made at Mauritius, and from information derived from the Logbooks of 30 vessels, whose tracks were across the Indian Ocean during that month.

The space over which these vessels were scattered extended, generally, from 20° N. and 39° §. to 90° E. and 15° E., in a belt from 20° to 30° in longitude, stretching obliquely across the ocean, from the southward of the Cape of Good Hope to the Bay of Bengal.

Very few of the observations were made to the westward of 60° and northward of 15° S., or to the eastward of 75° and southward of 15° 8.

With so few and imperfect data it is useless to expect to obtain precise and accurate results respecting almost any of the meteorological phenomena that presented themselves in the space within which the observations were taken ; while with regard to other parts of the ocean, the Journal affords no data whatever.

But information far short of absolute correctness may be of no small practical utility, as well as of scientific interest. Observations which are not sufliciently numerous or precise for the complete investigation of a phenomenon may, neverthe- less, place its existence beyond all doubt, and afford a rough view of the laws which it obeys. A general knowledge of this sort serves to point out the direction to be given to future observations, each fresh accumulation becoming the basis for another step in advance, till truth is at length fully attained.

Lhe Limits of the SE. Trade- Wind : -

During the first five or six days of the month the 8.H. Trade-wind extended much nearer to the Equator on the eastern than on the western side of the ocean.

If the positions of the vessels, and the direction of the winds, on each of those days be projected on a chart, the equatorial limits will be found to have stretched obliquely across the ocean, from the vicinity of Mauritius to 7° or 8° 8. and 85° E.

During the next seven days the equatorial limits gradually receded still further to the southward, on both sides of the ocean, but with nearly the same relative dis- tances from the Equator, till the Trade almost entirely disappeared.

On the 18th, 14th, and 15th, calms prevailed over several hundred miles around Mauritius, the Trade setting in far to the southward and westward of that tract, and appearing also to the northward and eastward of it.

From the 14th to the end of the month the Trade seems to have approached as near to the Equator on the western as on the eastern side of the ocean, but to have blown more strongly and steadily on the latter.

The mean equatorial and polar limits for the month were 11° 8, and 29° S. respec- tively, giving a mean breadth, in latitude, of eighteen degrees.

From the Ist to the 13th the western equatorial limits were, on an average, 19° 20' 8., or about eight degrees more to the south than the mean limits for the month. 'The mean western polar limits were 29° 17' S.,

The mean eastern equatorial limits for the same time were 11° 24' S., leaving a

* CHARLES MELDRUM, Esq., M.A., Secretary of the Mauritius Meteorological Society. This work was originally published in the colony, and has since been reprinted by the Board of Trade. Both issues are now scarce.

54: METEOROLOGICAL JOURNAL,

difference, between them and the western limits, of also eight degrees: the mean eastern polar limits, so far as they can be ascertained, were about 25° S.

From the 12th to the 16th, inclusive, the Trade-wind appeared, on the western side, as far south as 38°; that is, nine degrees beyond the mean polar limits.

After the 16th it gradually receded, till, by the 25th, the polar limits were in the vicinity of Mauritius.

But on the 30th it is again found as far south as Lat. 33° 4! S,

We thus perceive several distinct vibrations of the Trade-wind in the course of the month on its equatorial and polar borders. The western equatorial limits gradually receded from about 16° S. on the Ist and 2nd, to 26° S. on the 12th, and there seems, upon the whole, to have been, at the same time, asimilar contraction of the polar limits, till at length the Trade almost entirely disappeared. It is then found to have suddenly extended both north and south over 18° in the one direction and 18° in the other. After the 16th, again, the polar limits began gradually to recede, till they at length reached the vicinity of Mauritius. And then, on the 30th, they are once more found far to the southward, asif about to undergo a similar contraction.

It would seem that the northern limits approached nearest to the Kquator between the meridians of 65° and 75°.

Deflection of the SH. Trade-Wind to North and N.E. on its Kquatorial Borders : -

As a general rule the 8.H. Trade, on approaching the Kquator, is deflected to N. and N.E., forming aS. and then 8.W. wind, which lasts from a few hours to several days, according to the longitude. This is observed on almost every day of the month.

From a comparison of the observations, it appears that this deflection of the 8.E. Trade to N. and N.E. takes place to the eastward of 58° E. only, and that the space over which the 8.W. wind blows is greater on the eastern than on the western side of the ocean, gradually narrowing from about 86° E. to 60° and 58° Ei.

The extreme eastern limit for the month is 86° 39' E., and the extreme western 58° 35! E., the limits in latitude being 6° 1' N. and 15° 43! S.

The mean southern limits are 8° 32' S., and the mean northern limits 2° 4/ 8.

The average breadth in latitude is 5° 16', and in longitude 16° 4'.

Between the meridians of 75° and 85° the average breadth in latitude is about 10°, but it diminishes towards the meridian of Mauritius.

The prevailing direction is W.S.W., and the mean direction about 8.W. by W.

The mean daily force is 2°5.

The wind was lightest from the Ist to the 10th, and strongest from the 21st to the 29th, when it again became light.

Seventy-five observations contributed to the above data.

Deflection of the SL. Trade to S. and S.W. on its Southern Borders :- -

One of the most remarkable features presented by the charts is the constant preva- lence of a N.E. wind on the south-western limits of the Trade-wind.

There is hardly a day on which this N.E. wind is not found somewhere between the meridians of 14° and 70° E., blowing in strong gales over an extensive tract.

On the Ist of March we find four vessels, situated between Lat. 34° 46' 8., Long. 44° 50' E., and Lat. 31° 38'S., Long. 57° 48' E., experiencing N.E. and E.N.E. winds in moderate and fresh breezes during the whole day, and no other

INDIAN OCEAN, MARCH, 1853. 55

wind is observed in that space; while to the northward of it, as far as Lat. 16° 49'S., Long. 56° 21' E., the 8.E. Trade is blowing strongly and steadily, as shown by observations taken at five different places variously remote from one another.

On the 2nd of March this N.E. wind is still seen in the same locality, blowing in fresh breezes; but it now extends as far north as Lat. 24° 35' S., Long. 49° 27' E. Between that point and Lat. 35° 1'S., Long. 49° E., there were six vessels which had it c