Page:Popular Science Monthly Volume 32.djvu/332

318 stands alone, it is usually so much undermined that it resembles a low table with a single huge leg. There is a large perforation through the rocks at the southern extremity of Abaco, known as the "glass window," and also several submarine passages extending from one side of the island to the other. The rain carves grotesque forms out of the soft stone. This is sometimes coarsely honeycombed, or bristles all over with pinnacles or miniature chimneys, which are sharp as knife-edges, and compel you to use much caution in walking.

 (The tallest trees are Cocoanut Palms. The eroded table-shaped rock between the islands is from a sketch made at another point.

The dark-green foliage of the keys is frequently bordered by white, glistening lines, indicating beaches of coral-sand, which reflect the sun's rays with great power. Cocoanut palms find foothold along the shores, growing spontaneously from nuts cast up by the waves. In going northward from Green Turtle we pass successively Crab, Fiddle, Mun Jack, Ambergris, Spanish, Pensacola, Umbrella, Fish, Carter, Joe Keys, etc., and, in an opposite direction. Pelican Key, No Name Key, Great Guana Key, and numerous others.

The sharp contrast between the ordinary "white water" of the bay and the deep blue of the sea beyond the reefs, is very striking. The irregular black patches seen everywhere in the channel are due to algae or similar plants growing on the bottom. The sea-floor between Abaco and the reefs is elsewhere covered with the white coral-sand which causes a marvelously brilliant color-effect in strong lights, the tints ranging from the richest emerald to a transparent greenish-white.

Numerous sea-fowl show themselves as we sail past their haunts: brown pelican, standing immovable like statues on the rocks, but suddenly expanding into birds of astonishing size; men-of-war or frigate birds, whose dark, cleanly-cut forms are strongly silhouetted against the sky; flocks of black-headed gulls, standing in military order, each facing the same way, on the rocks, rise and whirl off at our approach.

At Fish Key we found a large colony of the sooty terns (Sterna fuliginosa), or "egg-bird," as the natives call them, just beginning to breed. This is a collection of wild-looking rocks, rising ten or fifteen feet above the sea like a row of petrified sand-dunes, which in reality they probably are, and covered with low shrubbery, grasses, and vines.