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APPENDIX

CONTAINING A DETAILED DESCRIPTION OF THE REEFS AND ISLANDS IN PLATE III.

In the beginning of the last chapter I stated the principles on which the map is coloured. There only remains to be said, that it is an exact copy of one by M. C. Gressier, published by the Depot General de la Marine, in 1835. The names have been altered into English, and the longitude has been reduced to that of Greenwich. The colours were first laid down on accurate charts, on a large scale. The data, on which the volcanoes historically known to have been in action, have been marked with vermillion, were given in a note to the last chapter. I will commence my description on the eastern side of the map, and will describe each group of islands consecutively, proceeding westward across the Pacific and Indian Oceans, but ending with the West Indies.

The WESTERN SHORES OF AMERICA appear to be entirely without coral-reefs; south of the equator the survey of the "Beagle", and north of it, the published charts show that this is the case. Even in the Bay of PANAMA, where corals flourish, there are no true coral-reefs, as I have been informed by Mr. Lloyd. There are no coral-reefs in the GALAPAGOS Archipelago, as I know from personal inspection; and I believe there are none on the COCOS, REVILLA-GIGEDO, and other neighbouring islands. CLIPPERTON rock, 10 deg N., 109 deg W., has lately been surveyed by Captain Belcher; in form it is like the crater of a volcano. From a drawing appended to the MS. plan in the Admiralty, it evidently is not an atoll. The eastern parts of the Pacific present an enormous area, without any islands, except EASTER, and SALA, and GOMEZ Islands, which do not appear to be surrounded by reefs.

THE LOW ARCHIPELAGO.

This group consists of about eighty atolls: it will be quite superfluous to refer to descriptions of each. In D'Urville and Lottin's chart, one island (WOLCHONSKY) is written with a capital letter, signifying, as explained in a former chapter, that it is a high island; but this must be a mistake, as the original chart by Bellinghausen shows that it is a true atoll. Captain Beechey says of the thirty-two groups which he examined (of the greater number of which I have seen beautiful MS. charts in the Admiralty), that twenty-nine now contain lagoons, and he believes the other three originally did. Bellinghausen (see an account of his Russian voyage, in the "Biblioth. des Voyages," 1834, page 443) says, that the seventeen islands which he discovered resembled each other in structure, and he has given charts on a large scale of all of them. Kotzebue has given plans of several; Cook and Bligh mention others; a few were seen during the voyage of the "Beagle"; and notices of other atolls are scattered through several publications. The ACTAEON group in this archipelago has lately been discovered ("Geographical Journal", volume vii., page 454); it consists of three small and low islets, one of which has a lagoon. Another lagoon-island has been discovered ("Naut. Mag." 1839, page 770), in 22 deg 4' S., and 136 deg 20' W. Towards the S.E. part of the group, there are some islands of different formation: ELIZABETH Island is described by Beechey (page 46, 4to edition) as fringed by reefs, at the distance of between two and three hundred yards; coloured red. PITCAIRN Island, in the immediate neighbourhood, according to the same authority, has no reefs of any kind, although numerous pieces of coral are thrown up on the beach; the sea close to its shore is very deep (see "Zool. of Beechey's Voyage," page 164); it is left uncoloured. GAMBIER Islands (see Plate I., Figure 8), are encircled by a barrier-reef; the greatest depth within is thirty-eight fathoms; coloured pale blue. AURORA Island, which lies N.E. of Tahiti close to the large space coloured dark blue in the map, has been already described in a note (page 71), on the authority of Mr. Couthouy; it is an upraised atoll, but as it does not appear to be fringed by living reefs, it is left uncoloured.

The SOCIETY Archipelago is separated by a narrow space from the Low Archipelago; and in their parallel direction they manifest some relation to each other. I have already described the general character of the reefs of these fine encircled islands. In the "Atlas of the 'Coquille's' Voyage" there is a good general chart of the group, and separate plans of some of the islands. TAHITI, the largest island in the group, is almost surrounded, as seen in Cook's chart, by a reef from half a mile to a mile and a half from the shore, with from ten to thirty fathoms within it. Some considerable submerged reefs lying parallel to the shore, with a broad and deep space within, have lately been discovered ("Naut. Mag." 1836, page 264) on the N.E. coast of the island, where none are laid down by Cook. At EIMEO the reef "which like a ring surrounds it, is in some places one or two miles distant from the shore, in others united to the beach" (Ellis, "Polynesian Researches," volume i., page 18, 12mo edition). Cook found deep water (twenty fathoms) in some of the harbours within the reef. Mr. Couthouy, however, states ("Remarks," page 45) that both at Tahiti and Eimeo, the space between the barrier-reef and the shore, has been almost filled up, – "a nearly continuous fringing-reef surrounding the island, and varying from a few yards to rather more than a mile in width, the lagoons merely forming canals between this and the sea-reef," that is the barrier-reef. TAPAMANOA is surrounded by a reef at a considerable distance from the shore; from the island being small it is breached, as I am informed by the Rev. W. Ellis, only by a narrow and crooked boat channel. This is the lowest island in the group, its height probably not exceeding 500 feet. A little way north of Tahiti, the low coral-islets of TETUROA are situated; from the description of them given me by the Rev. J. Williams (the author of the "Narrative of Missionary Enterprise"), I should have thought they had formed a small atoll, and likewise from the description given by the Rev. D. Tyerman and G. Bennett ("Journal of Voyage and Travels," volume i., page 183), who say that ten low coral-islets "are comprehended within one general reef, and separated from each other by interjacent lagoons;" but as Mr. Stutchbury ("West of England Journal," volume i., page 54) describes it as consisting of a mere narrow ridge, I have left it uncoloured. MAITEA, eastward of the group, is classed by Forster as a high encircled island; but from the account given by the Rev. D. Tyerman and G. Bennett (volume i., page 57) it appears to be an exceedingly abrupt cone, rising from the sea without any reef; I have left it uncoloured. It would be superfluous to describe the northern islands in this group, as they may be well seen in the chart accompanying the 4to edition of Cook's "Voyages," and in the "Atlas of the 'Coquille's' Voyage." MAURUA is the only one of the northern islands, in which the water within the reef is not deep, being only four and a half fathoms; but the great width of the reef, stretching three miles and a half southward of the land (which is represented in the drawing in the "Atlas of the 'Coquille's' Voyage" as descending abruptly to the water) shows, on the principle explained in the beginning of the last chapter, that it belongs to the barrier class. I may here mention, from information communicated to me by the Rev. W. Ellis, that on the N.E. side of HUAHEINE there is a bank of sand, about a quarter of a mile wide, extending parallel to the shore, and separated from it by an extensive and deep lagoon; this bank of sand rests on coral-rock, and undoubtedly was originally a living reef. North of Bolabola lies the atoll of TOUBAI (Motou-iti of the "'Coquille's' Atlas") which is coloured dark blue; the other islands, surrounded by barrier-reefs, are pale blue; three of them are represented in Figures 3, 4, and 5, in Plate I. There are three low coral-groups lying a little E. of the Society Archipelago, and almost forming part of it, namely BELLINGHAUSEN, which is said by Kotzebue ("Second Voyage," volume ii., page 255), to be a lagoon-island; MOPEHA, which, from Cook's description ("Second Voyage," book iii., chapter i.), no doubt is an atoll; and the SCILLY Islands, which are said by Wallis ("Voyage," chapter ix.) to form a GROUP of LOW islets and shoals, and, therefore, probably, they compose an atoll: the two former have been coloured blue, but not the latter.

MENDANA OR MARQUESAS GROUP.

These islands are entirely without reefs, as may be seen in Krusenstern's Atlas, making a remarkable contrast with the adjacent group of the Society Islands. Mr. F.D. Bennett has given some account of this group, in the seventh volume of the "Geographical Journal". He informs me that all the islands have the same general character, and that the water is very deep close to their shores. He visited three of them, namely, DOMINICANA, CHRISTIANA, and ROAPOA; their beaches are strewed with rounded masses of coral, and although no regular reefs exist, yet the shore is in many places lined by coral-rock, so that a boat grounds on this formation. Hence these islands ought probably to come within the class of fringed islands and be coloured red; but as I am determined to err on the cautious side, I have left them uncoloured.

COOK OR HARVEY AND AUSTRAL ISLAND.

PALMERSTON Island is minutely described as an atoll by Captain Cook during his voyage in 1774; coloured blue. AITUTAKI was partially surveyed by the "Beagle" (see map accompanying "Voyages of 'Adventure' and 'Beagle'"); the land is hilly, sloping gently to the beach; the highest point is 360 feet; on the southern side the reef projects five miles from the land: off this point the "Beagle" found no bottom with 270 fathoms: the reef is surmounted by many low coral-islets. Although within the reef the water is exceedingly shallow, not being more than a few feet deep, as I am informed by the Rev. J. Williams, nevertheless, from the great extension of this reef into a profoundly deep ocean, this island probably belongs, on the principle lately adverted to, to the barrier class, and I have coloured it pale blue; although with much hesitation. – MANOUAI or HARVEY Island. The highest point is about fifty feet: the Rev. J. Williams informs me that the reef here, although it lies far from the shore, is less distant than at Aitutaki, but the water within the reef is rather deeper: I have also coloured this pale blue with many doubts. – Round MITIARO Island, as I am informed by Mr. Williams, the reef is attached to the shore; coloured red. – MAUKI or Maouti; the reef round this island (under the name of Parry Island, in the "Voyage of H.M.S. 'Blonde'," page 209) is described as a coral-flat, only fifty yards wide, and two feet under water. This statement has been corroborated by Mr. Williams, who calls the reef attached; coloured red. – AITU, or Wateeo; a moderately elevated hilly island, like the others of this group. The reef is described in Cook's "Voyage," as attached to the shore, and about one hundred yards wide; coloured red. – FENOUA-ITI; Cook describes this island as very low, not more than six or seven feet high (volume i., book ii., chapter iii, 1777); in the chart published in the "'Coquille's' Atlas," a reef is engraved close to the shore: this island is not mentioned in the list given by Mr. Williams (page 16) in the "Narrative of Missionary Enterprise;" nature doubtful. As it is so near Atiu, it has been unavoidably coloured red. – RAROTONGA; Mr. Williams informs me that it is a lofty basaltic island with an attached reef; coloured red. – There are three islands, ROUROUTI, ROXBURGH, and HULL, of which I have not been able to obtain any account, and have left them uncoloured. Hull Island, in the French chart, is written with small letters as being low. – MANGAIA; height about three hundred feet; "the surrounding reef joins the shore" (Williams, "Narrative," page 18); coloured red. – RIMETARA; Mr. Williams informs me that the reef is rather close to the shore; but, from information given me by Mr. Ellis, the reef does not appear to be quite so closely attached to it as in the foregoing cases: the island is about three hundred feet high ("Naut. Mag." 1839, page 738); coloured red. – RURUTU; Mr. Williams and Mr. Ellis inform me that this island has an attached reef; coloured red. It is described by Cook under the name of Oheteroa: he says it is not surrounded, like the neighbouring islands by a reef; he must have meant a distant reef. – TOUBOUAI; in Cook's chart ("Second Voyage," volume ii., page 2) the reef is laid down in part one mile, and in part two miles from the shore. Mr. Ellis ("Polynes. Res." volume iii., page 381) says the low land round the base of the island is very extensive; and this gentleman informs me that the water within the reef appears deep; coloured blue. – RAIVAIVAI, or Vivitao; Mr. Williams informs me that the reef is here distant: Mr. Ellis, however, says that this is certainly not the case on one side of the island; and he believes that the water within the reef is not deep; hence I have left it uncoloured. – LANCASTER Reef, described in "Naut. Mag." 1833 (page 693), as an extensive crescent-formed coral-reef. I have not coloured it. – RAPA, or Oparree; from the accounts given of it by Ellis and Vancouver, there does not appear to be any reef. – I. DE BASS is an adjoining island, of which I cannot find any account. – KEMIN Island; Krusenstern seems hardly to know its position, and gives no further particulars.

 

ISLANDS BETWEEN THE LOW AND GILBERT ARCHIPELAGOES.

CAROLINE Island (10 deg S., 150 deg W.) is described by Mr. F.D. Bennett ("Geographical Journal", volume vii., page 225) as containing a fine lagoon; coloured blue. – FLINT Island (11 deg S., 151 deg W.); Krusenstern believes that it is the same with Peregrino, which is described by Quiros (Burney's "Chron. Hist." volume ii., page 283) as "a cluster of small islands connected by a reef, and forming a lagoon in the middle;" coloured blue. – WOSTOCK is an island a little more than half a mile in diameter, and apparently quite flat and low, and was discovered by Bellinghausen; it is situated a little west of Caroline Island, but it is not placed on the French charts; I have not coloured it, although I entertain little doubt from the chart of Bellinghausen, that it originally contained a small lagoon. – PENRHYN Island (9 deg S., 158 deg W.); a plan of it in the "Atlas of the First Voyage" of Kotzebue, shows that it is an atoll; blue. – SLARBUCK Island (5 deg S., 156 deg W.) is described in Byron's "Voyage in the 'Blonde'" (page 206) as formed of a flat coral-rock, with no trees; the height not given; not coloured. – MALDEN Island (4 deg S., 154 deg W.); in the same voyage (page 205) this island is said to be of coral formation, and no part above forty feet high; I have not ventured to colour it, although, from being of coral-formation, it is probably fringed; in which case it should be red. – JARVIS, or BUNKER Island (0 deg 20' S., 160 deg W.) is described by Mr. F.D. Bennett ("Geographical Journal", volume vii., page 227) as a narrow, low strip of coral-formation; not coloured. – BROOK, is a small low island between the two latter; the position, and perhaps even the existence of it is doubtful; not coloured. – PESCADO and HUMPHREY Islands; I can find out nothing about these islands, except that the latter appears to be small and low; not coloured. – REARSON, or Grand Duke Alexander's (10 S., 161 deg W.); an atoll, of which a plan is given by Bellinghausen; blue. – SOUVOROFF Islands (13 deg S., 163 deg W.); Admiral Krusenstern, in the most obliging manner, obtained for me an account of these islands from Admiral Lazareff, who discovered them. They consist of five very low islands of coral-formation, two of which are connected by a reef, with deep water close to it. They do not surround a lagoon, but are so placed that a line drawn through them includes an oval space, part of which is shallow; these islets, therefore, probably once (as is the case with some of the islands in the Caroline Archipelago) formed a single atoll; but I have not coloured them. – DANGER Island (10 deg S., 166 deg W.); described as low by Commodore Byron, and more lately surveyed by Bellinghausen; it is a small atoll with three islets on it; blue. – CLARENCE Island (9 deg S., 172 deg W.); discovered in the "Pandora" (G. Hamilton's "Voyage," page 75): it is said, "in running along the land, we saw several canoes crossing the LAGOONS;" as this island is in the close vicinity of other low islands, and as it is said, that the natives make reservoirs of water in old cocoa-nut trees (which shows the nature of the land), I have no doubt it is an atoll, and have coloured it blue. YORK Island (8 deg S., 172 deg W.) is described by Commodore Byron (chapter x. of his "Voyage") as an atoll; blue. – SYDNEY Island (4 deg S., 172 deg W.) is about three miles in diameter, with its interior occupied by a lagoon (Captain Tromelin, "Annal. Marit." 1829, page 297); blue. – PHOENIX Island (4 deg S., 171 deg W.) is nearly circular, low, sandy, not more than two miles in diameter, and very steep outside (Tromelin, "Annal. Marit." 1829, page 297); it may be inferred that this island originally contained a lagoon, but I have not coloured it. – NEW NANTUCKET (0 deg 15' N., 174 deg W.). From the French chart it must be a low island; I can find nothing more about it or about MARY Island; both uncoloured. – GARDNER Island (5 deg S., 174 deg W.) from its position is certainly the same as KEMIN Island described (Krusenstern, page 435, Appen. to Mem., published 1827) as having a lagoon in its centre; blue.

ISLANDS SOUTH OF THE SANDWICH ARCHIPELAGO.

CHRISTMAS Island (2 deg N., 157 deg W.). Captain Cook, in his "Third Voyage" (Volume ii., chapter x.), has given a detailed account of this atoll. The breadth of the islets on the reef is unusually great, and the sea near it does not deepen so suddenly as is generally the case. It has more lately been visited by Mr. F.D. Bennett ("Geographical Journal," volume vii., page 226); and he assures me that it is low and of coral-formation: I particularly mention this, because it is engraved with a capital letter, signifying a high island, in D'Urville and Lottin's chart. Mr. Couthouy, also, has given some account of it ("Remarks," page 46) from the Hawaiian "Spectator"; he believes it has lately undergone a small elevation, but his evidence does not appear to me satisfactory; the deepest part of the lagoon is said to be only ten feet; nevertheless, I have coloured it blue. – FANNING Island (4 deg N., 158 deg W.) according to Captain Tromelin ("Ann. Maritim." 1829, page 283), is an atoll: his account as observed by Krusenstern, differs from that given in Fanning's "Voyage" (page 224), which, however, is far from clear; coloured blue. – WASHINGTON Island (4 deg N., 159 deg W.) is engraved as a low island in D'Urville's chart, but is described by Fanning (page 226) as having a much greater elevation than Fanning Island, and hence I presume it is not an atoll; not coloured. – PALMYRA Island (6 deg N., 162 deg W.) is an atoll divided into two parts (Krusenstern's "Mem. Suppl." page 50, also Fanning's "Voyage," page 233); blue. – SMYTH'S or Johnston's Islands (17 deg N., 170 deg W.). Captain Smyth, R.N., has had the kindness to inform me that they consist of two very low, small islands, with a dangerous reef off the east end of them. Captain Smyth does not recollect whether these islets, together with the reef, surrounded a lagoon; uncoloured.

SANDWICH ARCHIPELAGO.

HAWAII; in the chart in Freycinet's "Atlas," small portions of the coast are fringed by reefs; and in the accompanying "Hydrog. Memoir," reefs are mentioned in several places, and the coral is said to injure the cables. On one side of the islet of Kohaihai there is a bank of sand and coral with five feet water on it, running parallel to the shore, and leaving a channel of about fifteen feet deep within. I have coloured this island red, but it is very much less perfectly fringed than others of the group. – MAUI; in Freycinet's chart of the anchorage of Raheina, two or three miles of coast are seen to be fringed; and in the "Hydrog. Memoir," "banks of coral along shore" are spoken of. Mr. F.D. Bennett informs me that the reefs, on an average, extend about a quarter of a mile from the beach; the land is not very steep, and outside the reefs the sea does not become deep very suddenly; coloured red. – MOROTOI, I presume, is fringed: Freycinet speaks of the breakers extending along the shore at a little distance from it. From the chart, I believe it is fringed; coloured red. – OAHU; Freycinet, in his "Hydrog. Memoir," mentions some of the reefs. Mr. F.D. Bennett informs me that the shore is skirted for forty or fifty miles in length. There is even a harbour for ships formed by the reefs, but it is at the mouth of a valley; red. – ATOOI, in La Peyrouse's charts, is represented as fringed by a reef, in the same manner as Oahu and Morotoi; and this, as I have been informed by Mr. Ellis, on part at least of the shore, is of coral-formation: the reef does not leave a deep channel within; red. – ONEEHOW; Mr. Ellis believes that this island is also fringed by a coral-reef: considering its close proximity to the other islands, I have ventured to colour it red. I have in vain consulted the works of Cook, Vancouver, La Peyrouse, and Lisiansky, for any satisfactory account of the small islands and reefs, which lie scattered in a N.W. line prolonged from the Sandwich group, and hence have left them uncoloured, with one exception; for I am indebted to Mr. F.D. Bennett for informing me of an atoll-formed reef, in latitude 28 deg 22', longitude 178 deg 30' W., on which the "Gledstanes" was wrecked in 1837. It is apparently of large size, and extends in a N.W. and S.E. line: very few islets have been formed on it. The lagoon seems to be shallow; at least, the deepest part which was surveyed was only three fathoms. Mr. Couthouy ("Remarks," page 38) describes this island under the name of OCEAN island. Considerable doubts should be entertained regarding the nature of a reef of this kind, with a very shallow lagoon, and standing far from any other atoll, on account of the possibility of a crater or flat bank of rock lying at the proper depth beneath the surface of the water, thus affording a foundation for a ring-formed coral-reef. I have, however, thought myself compelled, from its large size and symmetrical outline, to colour it blue.

SAMOA OR NAVIGATOR GROUP.

Kotzebue, in his "Second Voyage," contrasts the structure of these islands with many others in the Pacific, in not being furnished with harbours for ships, formed by distant coral-reefs. The Rev. J. Williams, however, informs me, that coral-reefs do occur in irregular patches on the shores of these islands; but that they do not form a continuous band, as round Mangaia, and other such perfect cases of fringed islands. From the charts accompanying La Peyrouse's "Voyage," it appears that the north shore of SAVAII, MAOUNA, OROSENGA, and MANUA, are fringed by reefs. La Peyrouse, speaking of Maouna (page 126), says that the coral-reef surrounding its shores, almost touches the beach; and is breached in front of the little coves and streams, forming passages for canoes, and probably even for boats. Further on (page 159), he extends the same observation to all the islands which he visited. Mr. Williams in his "Narrative," speaks of a reef going round a small island attached to OYOLAVA, and returning again to it: all these islands have been coloured red. – A chart of ROSE Island, at the extreme west end of the group, is given by Freycinet, from which I should have thought that it had been an atoll; but according to Mr. Couthouy ("Remarks," page 43), it consists of a reef, only a league in circuit, surmounted by a very few low islets; the lagoon is very shallow, and is strewed with numerous large boulders of volcanic rock. This island, therefore, probably consists of a bank of rock, a few feet submerged, with the outer margin of its upper surface fringed with reefs; hence it cannot be properly classed with atolls, in which the foundations are always supposed to lie at a depth, greater than that at which the reef-constructing polypifers can live; not coloured.

 

BEVERIDGE Reef, 20 deg S., 167 deg W., is described in the "Naut. Mag." (May 1833, page 442) as ten miles long in a N. and S. line, and eight wide; "in the inside of the reef there appears deep water;" there is a passage near the S.W. corner: this therefore seems to be a submerged atoll, and is coloured blue.

SAVAGE Island, 19 deg S., 170 deg W., has been described by Cook and Forster. The younger Forster (volume ii., page 163) says it is about forty feet high: he suspects that it contains a low plain, which formerly was the lagoon. The Rev. J. Williams informs me that the reef fringing its shores, resembles that round Mangaia; coloured red.

FRIENDLY ARCHIPELAGO.

PYLSTAART Island. Judging from the chart in Freycinet's "Atlas," I should have supposed that it had been regularly fringed; but as nothing is said in the "Hydrog. Memoir" (or in the "Voyage" of Tasman, the discoverer) about coral-reefs, I have left it uncoloured. – TONGATABOU: In the "Atlas of the Voyage of the 'Astrolabe'," the whole south side of the island is represented as narrowly fringed by the same reef which forms an extensive platform on the northern side. The origin of this latter reef, which might have been mistaken for a barrier-reef, has already been attempted to be explained, when giving the proofs of the recent elevation of this island. – In Cook's charts the little outlying island also of EOAIGEE, is represented as fringed; coloured red. – EOUA. I cannot make out from Captain Cook's charts and descriptions, that this island has any reef, although the bottom of the neighbouring sea seems to be corally, and the island itself is formed of coral-rock. Forster, however, distinctly ("Observations," page 14) classes it with high islands having reefs, but it certainly is not encircled by a barrier-reef and the younger Forster ("Voyage," volume i., page 426) says, that "a bed of coral-rocks surrounded the coast towards the landing-place." I have therefore classed it with the fringed islands and coloured it red. The several islands lying N.W. of Tongatabou, namely ANAMOUKA, KOMANGO, KOTOU, LEFOUGA, FOA, etc., are seen in Captain Cook's chart to be fringed by reefs, in several of them are connected together. From the various statements in the first volume of Cook's "Third Voyage," and especially in the fourth and sixth chapters, it appears that these reefs are of coral-formation, and certainly do not belong to the barrier class; coloured red. – TOUFOA AND KAO, forming the western part of the group, according to Forster have no reefs; the former is an active volcano. – VAVAO. There is a chart of this singularly formed island, by Espinoza: according to Mr. Williams it consists of coral-rock: the Chevalier Dillon informs me that it is not fringed; not coloured. Nor are the islands of LATTE and AMARGURA, for I have not seen plans on a large scale of them, and do not know whether they are fringed.

NIOUHA, 16 deg S., 174 deg W., or KEPPEL Island of Wallis, or COCOS Island. From a view and chart of this island given in Wallis's "Voyage" (4to edition) it is evidently encircled by a reef; coloured blue: it is however remarkable that BOSCAWEN Island, immediately adjoining, has no reef of any kind; uncoloured.

WALLIS Island, 13 deg S., 176 deg W., a chart and view of this island in Wallis's "Voyage" (4to edition) shows that it is encircled. A view of it in the "Naut. Mag." July 1833, page 376, shows the same fact; blue.

ALLOUFATOU, or HORN Island, ONOUAFU, or PROBY Island, and HUNTER Islands, lie between the Navigator and Fidji groups. I can find no distinct accounts of them.

FIDJI or VITI GROUP.

The best chart of the numerous islands of this group, will be found in the "Atlas of the 'Astrolabe's' Voyage." From this, and from the description given in the "Hydrog. Memoir," accompanying it, it appears that many of these islands are bold and mountainous, rising to the height of between 3,000 and 4,000 feet. Most of the islands are surrounded by reefs, lying far from the land, and outside of which the ocean appears very deep. The "Astrolabe" sounded with ninety fathoms in several places about a mile from the reefs, and found no bottom. Although the depth within the reef is not laid down, it is evident from several expressions, that Captain D'Urville believes that ships could anchor within, if passages existed through the outer barriers. The Chevallier Dillon informs me that this is the case: hence I have coloured this group blue. In the S.E. part lies BATOA, or TURTLE Island of Cook ("Second Voyage," volume ii., page 23, and chart, 4to edition) surrounded by a coral-reef, "which in some places extends two miles from the shore;" within the reef the water appears to be deep, and outside it is unfathomable; coloured pale blue. At the distance of a few miles, Captain Cook (Ibid., page 24) found a circular coral-reef, four or five leagues in circuit, with deep water within; "in short, the bank wants only a few little islets to make it exactly like one of the half-drowned isles so often mentioned," – namely, atolls. South of Batoa, lies the high island of ONO, which appears in Bellinghausen's "Atlas" to be encircled; as do some other small islands to the south; coloured pale blue; near Ono, there is an annular reef, quite similar to the one just described in the words of Captain Cook; coloured dark blue.

ROTOUMAH, 13 deg S., 179 deg E. – From the chart in Duperrey's "Atlas," I thought this island was encircled, and had coloured it blue, but the Chevallier Dillon assures me that the reef is only a shore or fringing one; red.