One of the most remarkable features connected with the Louisiade Archipelago is the manner in which its shores are protected by the coral reefs which have frequently been alluded to above. The principal of these are good examples of that kind distinguished by the name of barrier reefs. Rossel Reef has already been described, and the only other large one of this description which we saw more than a portion of, is that partially encircling South-east Island at a variable distance from the land, then passing to the westward as far as longitude 152 degrees 40 minutes, where it ceases to show itself above water; thence, however, the edge of a bank of soundings (represented on the chart by a dotted line) which is suddenly met with in coming from the deep blue unfathomed water to the southward, can be traced in a continued line to the westward as far as the Jomard Isles, whence it turns round to the northward for ten miles further, where our examination ended. This last may be considered as a submarine extension of the barrier, which probably reappears again above water, and passing to the northward of the Calvados Group, reaches as far as the northern entrance to Coral Haven, enclosing nearly all the high islands of the Archipelago. The expanse of water inside when not occupied by land usually exhibits a depth of from 15 to 30 fathoms, with numerous sunken patches of coral, and several reefs which partially dry at low-water. The shores of the islands also are generally protected by fringing coral reefs, the largest of which is that extending off the west and south side of Piron Island to a distance of seven or eight miles, with a well defined border towards Coral Haven.
At the western portion of the Louisiade Archipelago the reefs seen by us exhibit great irregularity of outline, continuity, and width. Some are linear reefs, others atolls* more or less distinct in character, and the remainder are usually round or oval. Viewed as a whole they form an interrupted chain, with numerous deepwater channels, which terminates in the West Barrier Reef of the chart but is connected with the coast of New Guinea by a bank of soundings, with, probably, a well-defined margin. Many low, wooded islands are scattered along this line. I know of no distinguishing feature presented by the coral reefs of the Louisiade compared with those which I have seen elsewhere. One remarkable occurrence, however, connected with them, may be mentioned. While passing in the ship the most northern point of Rossel Island, I observed upon the reef, about a hundred yards inside its outer border, a series of enormous insulated masses of dead coral rising like rocks from the shallow water. The largest of these, examined through a good telescope from the distance of half a mile, was about twenty feet in length and twelve in height, with a well-defined high-water mark. It formed quite a miniature island, with tufts of herbage growing in the clefts of its rugged sides, and a little colony of black-naped terns perched upon the top as if incubating.
(*Footnote. "An atoll differs from an encircling barrier reef only in the absence of land within its central expanse; and a barrier reef differs from a fringing reef in being placed at a much greater distance from the land with reference to the probable inclination of its submarine foundation, and in the presence of a deep water lagoon-like space or moat within the reef." The Structure and Distribution of Coral Reefs by Charles Darwin page 146.)
THEORY OF THEIR FORMATION.
I had only once before seen a similar exhibition of such great and permanently elevated masses of dead coral upon a living reef--a phenomenon of much interest in connection with Mr. Darwin's theory of the mode of formation of coral reefs. This was on a portion of the Great Barrier Reef of Australia, visited in company with Mr. Jukes, who has published a detailed account of it.* In both cases the only obvious explanation is that these huge blocks--too massive to have been hove up from deep water into their present position by any storm--reached their present level by the elevation of the sea bottom on which they were formed.
(*Footnote. Voyage of H.M.S. Fly by J.B. Jukes volume 1 page 340.)
Before quitting the subject of the coral reefs of the Louisiade I may be permitted to express my conviction of the perfect manner in which many, perhaps all of the appearances which they present may be satisfactorily accounted for by the application of Mr. Darwin's theory. We have only to presume the whole of the Archipelago to have once formed part of New Guinea--a supposition highly probable in itself (suggested even by a careful examination of the large charts) and strengthened by the total absence of signs of volcanic agency in what the theory in question would require to be an area of subsidence as opposed to those of elevation, such as are known to exist in parts of New Guinea.
ETHNOLOGY OF NEW GUINEA.
The ethnology of New Guinea is involved in so much confusion and obscurity for the want of sufficient data, that even with the aid of some additional recently acquired information bearing upon the subject, I wish the following brief remarks to be regarded more as probable assumptions than as views the correctness of which admits of demonstration. Besides, to give all the proofs, such as they are, would cause much repetition of what has been already stated above.
I must premise that most of our previous definite information regarding the inhabitants of New Guinea applies only to a small portion of the north-west coast of that great island in the neighbourhood of Port Dorey, which is known to be peopled by several distinct varieties of mankind, of which one (with which, as occupying the coast, we are best acquainted) is designated the Papuan, or Papua, as generally understood by that appellation when used in its restricted signification. These Papuans, according to Dumont D'Urville,* compose the principal part of the population of Port Dorey, and, judging from his description, I have no hesitation in referring to them also the inhabitants of the Louisiade Archipelago and the South-East coast of New Guinea, and agree with Prichard (in opposition to the views of others) that they "constitute a genuine and peculiar tribe."**