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The group at the mouth of the Orinoco was formed by an accumulation of trees, weeds, sand and mud, during the various inundations of that river. Some of these islands abound in palms and cocoa trees ; upon the tops of which live in huts an Indian tribe, called Guaröus. These aërial habitations are covered with palm-leaves ; and cocoa trees furnish their inhabitants with wood for fuel; food and beverage. The Guaröus are social and hospitable; and are at peace, even with the Spanish settlers. Secured by their height from the inundations of the river, they live in peaceful enjoyment; are passionately fond of dancing; and derive no little profit from trading in various species of fish ; which their dogs assist them to catch, in nets, in hammocks, and in baskets. They are frequently called the Palm-tree Nation ; and their numbers vary from 10 to 12,000.
The African Atlantic islands are of basaltic formation, and of submarine volcanic origin a Amsterdam Island had a similar formation b; and the eruptions of the several different periods were observed by Dr. Gillan, to be distinctly marked in regular divisions by different layers. 1st. A layer of vegetable mould; 2d, volcanic ashes ; 3d, celular lava ; 4th, compact lava ; and 5th, glassy lava".
• Professor Smith. Tuckey, p. 29, 4to. • The process is obvious whereby even solid rocks are converted into soil, fit for the maintenance of vegetation, by simple exposure to atmospheric agency; the disintegration produced by the vicissitudes of heat and cold, moisture and dryness, reduces the surface of almost all strata to a comminuted state of soil, or mould, the fertility of which is usually in proportion to the compound nature of its ingredients.—Buckland's Bridgewater Treatise, p. 69.
This island is about 2,000 miles from shore, and lies midway between New Holland and Madagascar. It is eight square miles in surface. Zeolite, obsidian, and pumice are seen in every part of the coast. There are many boiling springs; and whenever the ear is applied to the earth, a noise is heard like the bubbling of water. There is not one quadruped, nor one land-bird ; and, if we except flies, not one visible insect. There are mosses, sow-thistles, garden parsley, procumbent pearlwort, polypody, spleenwort, and a few other plants ; and, what is extremely curious, they are all British. The gardeners of the Lion, on their voyage to China, planted potatoes here.
It is many ages before a coral rock becomes so deeply covered with soil, as to bear the bread-fruit tree. In some islands of the Pacific, pandangs, sago-palms, casuarinas, and the Barringtonia, will grow to a great size ; but the breadfruit will not ; and this, not because it is unadapted to the climate, but because it has not the power of insinuating its roots into the coral rocks; of which those islands are, in a great measure, composed.
Palmerstone Island is of still more recent formation a. It is a mile only in circumference; and it is composed of coral sand, mixed with blacker earth. Upon it grows scurvy-grass and cocoa trees; and though the soil is poor, there are a great many shrubs and trees. That it possesses men of war and tropic birds, with crabs crawling among the bushes, is not much a subject for wonder; but that in one part of the reef there should be a lake, full of blue, black, red, and yellow fishes, is a phenomenon, for which it is now, perhaps impossible to account.
Sponges in Italy are found rooted on hard flints b; and on the amphitheatre near Albano, several trees have insinuated large roots between the best cemented stones. The lichen calcareum even vegetates on the naked rock; and draws its chief nourishment from the air. This, decaying, furnishes a bed and a little moisture to maintain a moss. The moss
• Captain Colebrooke, in his account of Barren Island, has the following remark :-“ From the singular appearance of this island, it might be conjectured, that it has been thrown up entirely from the sea, by the action of subterranean fire. Perhaps, but a few centuries ayo, it had not reared itself above the waves ; but might have been gradually emerging from the bottom of the ocean, long before it became visible; till at length it reached the surface, when the air would naturally assist the operation of the fire, that had been struggling for ages to get vent, and it would then burst forth. The cone or volcano would rapidly increase in bulk, from the continual discharge of lava and combustible matter; and the more violent eruptions, which might have ensued at times, when it would throw up its contents to a greater elevation and distance, might have produced that circular and nearly equidistant ridge of land we see around it.”-Asiatic Researches, vol. iv. p. 413, 14.
b Misson, ii. p. 399.
yields to the course of Nature, decomposes, and adds to the previous soil. Seeds of other vegetables are wafted by the winds, or dropped by birds ; and thus the bare rock, after a series of ages, becomes green with vegetation.
Christmas Island, in the South Seas, is composed of sand, rotten vegetables, dung of birds, decayed shells, broken coral stones, and other marine productions. There is no fresh water; and therefore no inhabitants : but there are marine birds, land crabs, and lizards. The two clusters of islands, lately discovered, are but now emerging, as it were, into visible existence. They are so low, that they can be seen from the deck, even in the day time, only when ships are very near. They were discovered by De Peyster, while sailing from Valparaiso to the East Indies. To the former cluster he gave the name of Ellice's Group; to the latter, that of De Peyster's Islands. They were totally uninhabited. Byron and Wallis had previously borne down near these islands; but, from their lowness, they did not discover them.
Some suppose, that land is entirely derived from the exuviæ of marine animals. That the earth possesses a renovating power is certain. Islands expand, and become elevated by the combined influence of heat and water. The power, which heat possesses, of dilating bodies, arises out of its faculty of forcing itself between their separate particles. This, as a natural consequence, causes them to occupy a larger space than before.
THE MANNER IN WHICH ISLANDS ARE FIRST PLANTED ; AND
BECOME PEOPLED WITH ANIMALS. The manner in which distant islands become planted with vegetation is exceedingly curious. The Pacific Islands afford instances, from which the various methods may be success
a May 17th, 1819—long. 180° 54' W., lat. 8° 29' S.-long. 181° 43' W., lat. 8° 5 S.
fully developed. How European and American fruits came to be naturalized in some of those islands is sufficiently obvious. Some have been carried thither by accident; some for delight; and others for subsistence. Some have been mixed with other seeds; and thus been transported against the will and wish of the transporters; as darnel amongst rye, and melilot amongst wheat. Cook planted the pine-apple and melon in Eoha; on Christmas Island yams and cocoas ; on Lefooga melons, pumpkins, and Indian corn. Vancouver planted water-cresses and vine-cuttings in New Holland ; on the Island of Cocos peas, beans, apples, melons, and peach-stones. Captain Colneth had previously left a variety of garden-seeds. On other islands he had also introduced the almond. Wilson planted the bread-fruit tree a on the Palmerstone Islands. In Otaheite successive navigators have introduced various species of plants and vegetables : and other islands have been benefited in a similar manner.
But as the mode, in which these islands became rich in what we now call native plants, is a subject of some difficulty, we will assist in the endeavour to explain it.
One of the circumstances, on which Columbus and his crew founded their hopes of being near land, was that of the Nigna taking up a branch, the red berries of which were as fresh, as if they had been taken immediately from the tree. Philips, also, in his voyage to Botany Bay, saw a great number of cocoa-nuts, floating at a great distance from shore b; and Captain Tuckey found several floating patches of reeds and trees, forty leagues from the African coast. Near one of the Aleutian Islands Captain Kotzebue picked up the log of a camphor-tree; and fell in with an iceberg, having a portion of its surface lined with earth; in which grew trees and other vegetable substances a.
a This tree, so abundant in its useful qualities, is yet held in little esteem in the islands of India.—Crawford's Indian Archipelago, i. 413.
b Near Cape Musseldom the Indians throw cocoa-nuts, flowers, and fruits into the sea, to ensure a quick passage, and a safe voyage.
• Narrative, p. 55, 4to. :
The Canadians had formerly a custom of planting large trees on the ice. These remained the whole winter; and being evergreen, “you frequently appear,” says Aubery b, “ to be travelling through an avenue of pines.” These, on the melting of the snow, float down to the sea. From the western shores, also, of America pines float to the Pacific Islands; an instance of which is afforded by the circumstance of two large canoes having been made of pine at Mowee and Attowai. The pine, as a living tree, is unknown in those islands. Indeed the American rivers, both north and south, during the time of their respective inundations, carry an inconceivable quantity of logs, weeds, shrubs, and other plants, down to the ocean. Large trees, too, of American growth are frequently picked up on the beach in the Azores. On the same coast, previous to the time of Columbus, a new continent and a new race of men were indicated by the appearance of a bamboo, and two dead bodies, having features and complexions widely differing from those of any men, at that time known.
After violent storms cocoa-nuts are picked up on the beach of the North Seas. On the Shetland and Orkney Islands are occasionally thrown up fruits, belonging to the torrid hemisphere of America ; on the shores of the Hebrides seeds from Jamaica ; and on those of Ferro and Gomera, plants from St. Domingo. Seeds, cast on the coasts of Ireland and Norway d, will sometimes take root and flourish.
* The only insect seen by Captain Parry, in the higher arctic regions, was the Aphis borealis, which he found on floating floes of ice in the Polar Sea, and as far north as 82%0. “Its near resemblance to Aphis pices, which feeds on the silver fir, would induce the belief, that the floating trees of fir, that are to be found so abundantly on the shores and to the north of Spitzbergen, might be the means by which this insect was transported to the northern regions." P. 201, 4to.
b Trav. i. p. 208.