Page:Journal of the Royal Geographical Society of London, Volume 1 (2nd edition).djvu/89

Rh formation,—the sand and fragments dug out of the wells near the middle of the isles, being altogether of the same material, rounded by attrition in water, with that which at present constitutes the shores and beaches. The circular form of the group, as well as of the detached northernmost or Keeling Isle, may, however, countenance the idea of their being originally bared on submarine volcanoes long extinguished, though no traces of the occurrence of earthquakes, or other natural convulsions, are now discernible.

Around the exterior of the isles the shore is heaped up by the surf from twelve to twenty-one feet above the level of the sea (high-water mark); and the interior is not in general elevated more than from three to six feet above that level.

The soil is mainly composed of fine calcareous sand; in some parts marly, in others consisting of rounded pieces of coral and shells, with a small mixture of vegetable earth. It is from one to two feet deep, and lies on a strong platform of aggregated coral and shells. Quantities of pumice-stone and lava are thrown on shore by the sea, which, by decomposition, gradually add some earthy matter.

The general produce of the isles is, first, the cocoa-nut palm-tree, which, when properly thinned out, may be exacted to yield as abundantly as in any part of the world.

Second.—A tree producing hard wood of a dark color, fit not only for fuel, but for timbers of small craft, and vessels, up to three hundred tons.

Third.—A tree having a leaf resembling in size and form the leaf of the boxwood. The timber is hard and heavy, of a reddish colour, fit for small parts of machinery and boats' timbers. The bark, having an uncommonly large portion of tannin, may be useful for making leather, and preserving nets.

Fourth.—A large straight-growing tree, which furnishes poles and small spars for rafters. It is durable under cover, but subject to rapid decay when exposed to the weather.

Fifth.—Another large straight-growing tree, with leaves and fruit resembling the jack-in-the-box of the West Indies. The timber is, however, soft and of little value.

Sixth.—A tree frequently of large dimension, the wood of which decays even faster than it dries. Its leaves may be used as greens: they are good food for hogs; and, with the trunks, supply a considerable quantity of vegetable matter to the soil.

Seventh.—The tree called warroo by the Javanese. It is planted by them in front of their houses for the sake of its shade and flowers. The timber is useful and durable; and, when of large growth, the bark affords a material for making twine or fishing lines.

Eighth.—The chinkauen, or dadap, a soft-wooded, green,