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covered, lose their adhesive property; and remaining in a loose state, form what is usually called a key, upon the top of the reef. The new bank is not long in being visited by sea birds; salt plants take root upon it, and a soil begins to be formed; a cocoa nut, or the drupe of a pandanus is thrown on shore; land birds visit it and deposit the seeds of shrubs and trees; every high tide, and still more every gale, adds something to the bank; the form of an island is gradually assumed; and last of all comes man to take possession.

Half-way Island is well advanced in the above progressive state; having been many years, probably some ages, above the reach of the highest spring tides, or the wash of the surf in the heaviest gales. I distinguished, however, in the rock which forms its basis, the sand, coral, and shells formerly thrown up, in a more or less perfect state of cohesion; small pieces of wood, pumice stone, and other extraneous bodies which chance had mixed with the calcareous substances when the cohesion began, were inclosed in the rock; and in some cases were still separable from it without much force. The upper part of the island is a mixture of the same substances in a loose state, with a little vegetable soil; and is covered with the casuarina and a variety of other trees and shrubs, which give food to paroquets, pigeons, and some other birds; to whose ancestors it is probable, the island was originally indebted for this vegetation.

The latitude of Half-way Island, deduced from that of the preceding and following noons, is 10° 8′ south, and longitude by time keeper corrected, 143° 18′ east. From the time of anchoring, to nine at night, there was a set past the ship to the north-east, of half a knot; it ceased for three hours, then recommencing at a slower rate, ran to the same point. Thus far in the strait, the current had been found to run at the rate of fourteen miles a day to the westward; and the above set might have been an eddy under the lee of the reef, for it seemed too irregular to be a tide.

At daylight in the morning the south-east trade blew fresh,