On the 11th a few white tern were seen near the ship, (in lat. 28°. S. and long. 180°.) and as she was about 120 miles from any land then known, this notice may help to show within what limits the sight of those birds may be considered to indicate the vicinity of land. I am not at all surprised that the early voyagers should have taken so much notice of the appearance and flight of birds, when out of sight of land; since in my very short experience I have profited much by observing them, and I am thence led to conclude that land, especially small islands or reefs, has often been discovered in consequence of watching particular kinds of birds, and noticing the direction in which they fly, of an evening, about sunset. Short winged birds, such as shags or boobies, seldom go a hundred miles from land, and generally return to their accustomed roosting place at night; and even those with longer wings which fly farther, do not habitually remain on the wing at night, though they are known to do so sometimes, especially if attracted by a ship, on which, doubtless, they would perch if she were to remain motionless, and her crew were to be quiet for a short time. Mistakes may occur in consequence of floating carcases, trunks of trees, wrecks of vessels, or drifting seaweed, all which attract birds and afford them rest at night; but, generally speaking, if there is land within fifty miles of a vessel, its existence will be indicated, and the direction in which to look will be pointed out by birds. Decided oceanic fowl, such as albatrosses and all the petrel family, sleep upon the surface of their favourite element; therefore the flight of that description of bird can be no guide whatever, except in the breeding season, when they frequent the vicinity of land.
Until I became aware of these facts, the discovery of the almost innumerable islands in the great ocean of Magalhaens, (erroneously, though now probably for ever called Pacific,) caused great perplexity in my mind. That Easter Island, for instance, such a speck in the expanse, and so far from other land, should have been — not only discovered — but repeatedly visited and successively peopled, by different parties of the human family, seemed extraordinary, but now, connecting the numerous accounts related by voyagers of canoes driven hundreds of miles away from their desired place, with these facts respecting birds, much of the mystery seems unravelled.
Every one is well aware that uncivilized man is more attentive to signs of weather, habits of animals, flight of the feathered tribe, and other visible objects, important to his very existence, than his educated brother,—who often diminishes the perceptive faculties of the mind, while he strengthens the power of reflection and combination.