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of the latest charts, it would be well that its non-existence should be equally proved by the American Expedition.

IV. The Solomon Islands.-These islands have partly been visited by D'Urville and Shortland, partly by D'Entrecasteaux; and several English ships have at different times sailed through them; but a complete survey of all the islands composing this great archipelago is still wanting. It is indeed very singular that, of all the navigators who have lately visited the Pacific Ocean, none have ever attempted any thing like a systematic survey of these islands, with the exception of D'Entrecasteaux, who, at least, sailed along the southern islands, from east to west, and thus greatly improved the hydrography of them. I have published, in the year 1827, a chart of these islands, (Carte Systématique de l'Archipel des Isles Salomon.) Having collected all the materials that were to be had at that time, many of them in apparent contradiction to each other, I endeavoured to reconcile them, and to delineate the islands belonging to this archipelago, to the best of my judgment. (An account of my proceedings will be found in the Memoir accompanying my chart.) By the first survey of these islands, it will be seen whether some of my combinations have been well founded or not. The Solomon Islands being the greatest archipelago in the Pacific Ocean, and the least known, deserve, no doubt, to be as completely surveyed as the Society, Friendly, or other groups. Although ten years have elapsed since my chart was published, nothing has been done since that time for the hydrography of these islands, to enable me to improve the second edition of that chart, (1836,) except in the situation of a group of islands, discovered lately, to the northward of the Solomon Islands.

V. New Caledonia.-A dangerous reef has lately been discovered by the ship Petrie, to the northward of New Caledonia; the precise position of this danger ought to be determined.

VI. Loyalty Islands.—Captain D'Urville has been the first to survey the Loyalty Islands; but having sailed only along the northern side of them, it is to be wished that the southern shore might also be surveyed.

VII.* The Feejee Islands.-Captain D'Urville has done a great deal to give us a more correct chart of these islands, having surveyed a great part of them; but still he has left unexplored many islands belonging to this archipelago. In my supplementary memoir to the chart of these islands, I have endeavoured to combine Captain D'Urville's survey with such surveys as had been made previous to his voyage; and have constructed, according to all the data that have come to my knowledge, a new chart of the Feejee Islands, (named by Captain D'Urville, Viti Islands.) Of course the chart cannot be very

correct, but it may perhaps serve till a new complete survey is made of them.

VIII. New Ireland. It is astonishing that nearly two centuries have elapsed without the islands situated to the north of New Ireland -first seen by Tasman, and since by Dampier and Bougainville— having been examined, so that we know as little of them as was known one hundred and fifty years ago. There remains, then, to be made a complete survey of all these islands. As to the islands near them, seen by Maurell, it is not likely that they are the same, as some have supposed. This is another reason why they should be all explored with the greatest precision.

IX. Admiralty Islands.-It is much to be wished that the islands seen by Maurell, to the eastward of the Great Admiralty Island, should be explored, since we know that Maurell's account of his discoveries does not satisfy the hydrographer.

X. New Britain.-Admiral D'Entrecasteaux has seen and determined, with his usual exactness, the islands situated along the north coast of New Britain; but he has not been able to lay down the coast itself, which he has seen only at a distance, and some parts not at all.

XI.* Low Islands.-Captain Hagemuster, of the Russian navy, discovered, in the year 1830, an island to the westward of King George's Islands. This island cannot be any other than Schouten's Waterlandt. Captain Wilson sailed between two islands, which he took to be King George's Islands. Most navigators have been of the same opinion; although there is a difference of longitude of more than a degree between the islands seen by Wilson and King George's Islands. Captain Duperrey, (an excellent authority, as every hydrographer will readily admit,) is of a different opinion; he maintains that the two islands between which Wilson sailed are not King George's Islands, but are situated to the westward of them. He thinks that the island seen by Captain Hagemuster, which I take to be Waterlandt, is one of the two islands; and that Captain Hagemuster has not seen the other. In order to refute Captain Duperrey's hypothesis, the second island, which, according to him, Captain Hagemuster might not have perceived, ought to be searched for, to the westward of Captain Hagemuster's island; if it really does exist, it cannot be at a greater distance than about fifteen or twenty miles.

XII.* Commodore Byron's Isles of Disappointment have not been visited since their first discovery in 1765. I have endeavoured to

settle their longitude at 140° 42′ W. (page 87 of my supplement); but this being only an approximation, they ought to be surveyed-at leas visited anew.

XIII. By my Memoirs, page 281, and supplement, page 90, you will perceive that there is a difference of 27' between Captain Bellinghausen's and Captain Kotzebue's longitude of the west point of Prince of Wales's Island* and the island situated to the westward of it.† What may be the cause of this difference? since the two navigators do not differ, either before or after, more than three minutes. Either the length of Vlighen Island has been overrated by Captain Kotzebue, or some other error has crept into the longitude of either the one or the other. As both are excellent observers, it would be very desirable to settle this point, by examining and surveying carefully all the islands lying to the westward and eastward of Vlighen Island, and determine with the greatest precision the width of the channels separating the different islands, as well as the exact length of Vlighen or Prince of Wales's Island: the error will, most likely, be detected in the length of that isle.

XIV.* There is a difference of 17' in the longitude of the isle Clermont de Tonnerre between Captain Duperrey and Captain Beechey. At Serle Island, close to it, there is hardly any difference at all. The same difference of 17' exists in the longitude of Prince William Henry, which Captain Beechey has proved to be the same with Captain Duperrey's isle Lortingo; whereas at Mollu Island, both Captains Beechey and Duperrey agree perfectly well. It would be worth while to search for the cause of such anomalies.

XV. Captain Beechey is of opinion that Captain Duperrey's isle Clermont de Tonnerre is one and the same with the island of Minerva. Captain Duperrey, on the contrary, maintains that the island Minerva is the same as Serle Island. I am of this latter opinion; although the solution of this problem will much depend upon the distance of the island Clermont de Tonnerre from Serle Island, which is much less on Duperrey's chart than on Captain Beechey's.

XVI. There has been lately discovered an island of considerable extent, of the name of Raraka. It would be well to examine it, since the account given of it is not quite satisfactory. It is stated to be situated in 16° 3' S., and 145° 0′ W.

XVII.* I have placed on my chart of the Low Islands, several islands, the position of which is rather doubtful; for instance, the Bunyer's Group of Turnbull, the island of Britomart, the islands discovered by Quiros, and several others. In order to have any certainty about their existence and precise position, it is necessary to search for and make a survey of them.

* On some charts this island is named Dean's Isle; on my charts Vlighen Isle.
+ By Captain Porter called Gamble; by Captain Kotzebue, Krusenstern Island.

It

XVIII.* The Islands of San Bernardo and the Islands of Danger.Mendane discovered a group of islands, named by him San Bernardo. These islands have been seen by Captains Freycinet and Bellinghausen. Not far from them Byron discovered a small group, which he named Islands of Danger. Notwithstanding a difference of latitude of half a degree, the two groups have been considered as one and the same. has not been thought impossible that in Byron's latitudes there might have been a typographical error: besides, none, of all the navigators who have passed here, have ever found a second group, which they could not have missed if it really existed. Captain Duperrey, however, who is, as I have said above, a high authority in whatever relates to the hydrography of the South Seas, is of a different opinion: he maintains that Byron's Islands of Danger do exist. In order to settle that question, it is necessary to search under the meridian of the islands San Bernardo, as determined by Captain Bellinghausen, for these Islands of Danger in the latitude assigned to them by Byron, as well as for the chain of rocks of which he speaks, and which are situated, according to him, to the eastward. This has not been done. yet, and it would be very desirable if it was done, in order not to leave the least doubt on the subject.

XIX.* Marianne Islands.—On Captain Freycinet's chart there is to be seen, to the southwest of the island of Assumption, rocks, by the name of Mary's. Rocks of the same name have been seen by La Perouse, to the northward of Assumption Island. In case the Expedition should extend its exploratory researches to the northern hemisphere, this doubtful point should be settled.

XX. Caroline Islands.-These islands have been so well surveyed by Captain Duperrey and Captain Lütke, that there is very little now left to be done concerning them. I shall, however, point out here some islands that require to be determined with great precision: 1. The island named by Captain Morell, Fasolis, is most likely the same with Captain Lütke's, Farroilep; but a difference of 21′ in latitude, makes

this doubtful.

2. Island Lydia, on Captain Duperrey's chart. We do not know by whom it has been discovered, nor who has determined its 3. I have endeavoured to prove, in my Supplementary

situation.

This

4. The Monteverde Islands ought

Memoir of the Caroline Islands, that the islands Bordelaire, Fame, Campbell, and the island St. Augustine, are one and the same. hypothesis requires to be verified. to be surveyed; what Captains Monteverde and Morell, the only navigators who have seen them, have said of them, is not sufficiently

satisfactory.

5. We see on Captain Duperrey's chart of the Caroline

Islands, several islands, of which we know nothing more than the

name, viz.: Bumkay's, Quekin's, &c., and their existence and position remain to be ascertained. 6. The island of Arrecifos has, so far as my knowledge extends, been seen only by the ship Providence, in the year 1811. Not knowing much respecting it, it is to be wished that it should be surveyed.

XXI.* The Island of Gilbert.-At the end of my supplementary volume, I have pointed out what remains to be done in order to have a perfect knowledge of all the islands belonging to this archipelago.

Remark. Independent of the American Exploratory Expedition, there are to be at the same time three others in the South Seas: two English and one French expedition. Many of the islands will of course be visited by all the expeditions; and it is to be apprehended that their longitudes, determined by the different astronomers of the expeditions, will, perhaps, not agree so well as might be wished. This difficulty will of course be obviated, by referring their astronomical observations to the longitudes of such places as are determined by absolute astronomical observations with the greatest precision, and those most likely to be visited by the ships of the expeditions. The positions we have in the South Seas, are Point Venus, in longitude 149° 29′ 17′′ W., determined by the passage of Venus over the disk of the sun; Port Honolulu, in the island of Oaho, by occultation of several stars, in 202° 10' E.; and Port Jackson, Sydney Cove, in 151° 17′ E., by an eclipse of the sun. In the northern part of the Pacific, East Cape 190° 16′ 10′′ E., may be adopted as a well-fixed point, although not determined by absolute astronomical observations. With respect to the coast of South America, Talcahuana, the longitude of which was determined by Captain Beechey, to be in 72° 56′ 59′′ W., seems to me a well-determined point. Captain Duperrey is not of that opinion; and it remains to be settled whether the longitude of Talcahuana, or Valparaiso, in 71° 33′ 34′′ W., deserves the preference.

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I have the honour to state, that since my arrival here, I have examined the General Requisition, complained of by Commodore Warrington and the Commissioners of the Navy, and find (as I was well aware was the case) it duly approved by me.

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