principally live'.

This gum is transparent, and resembles gum arabic. The leaves of the mimosa afford food for the camelopard; and its boughs shelter the loxia: the smoothness of its rind preventing their eggs from being sucked by snakes. Of this bird, there are from 800 to 1000 nests under the same roof. These collections are sometimes so large, that the trees bow down by the weight of them2: and they are covered like the roofs of houses; to which there are many entrances, each of which forms a street; nests being on each side.

CHAPTER XI.

BEES bear a striking analogy, as we have before observed, to the corallina. By the silent labours of this small worm have immense marine continents been formed. Reefs extend upon the coast of Abyssinia; in the Red Sea; in the Mediterranean; on the Gold Coast of Guinea3; on those of China, Japan, Corea1, and in the Straits of Sunda; while they extend along the whole eastern coasts of Austral Asia; and are found in almost

2 Ib. p. 134.

1 Vid. Paterson's Travels in Africa, 4to. p. 125. ed. 1790. 3 On this coast are two species of coral; one of which in Bosman's* time was called Conta de Terra; the other was of a blue colour. The latter was valued at its equal weight in gold; the former at four times its weight.

* Vid. Captain Hall's Voyage of Discovery to the west Coast of Corea and Loo-choo Islands, 4to. p. 107, 8, 9. The Loo-choos call coral ooroo.Vid. Clifford's Vocabulary.

* Guinea Coast, p. 103. ed. 1721.

every part of the Pacific, covering not only detached parts, but extending several thousand square leagues.

Thus islands are formed. The corallina, with gradual, but incessant, labour, raise their foundations from the bed of the ocean on these reefs', after an interval, the high tides deposit sand, shells, pumice, pebbles, mud, weeds; pieces of coral, roots, wood, and other soil. Birds then begin to settle upon them; salt plants take root upon them; tropical trees, vegetables, seeds, and shells, are washed upon them; and birds deposit their exuvia. In this manner islands are formed into groups and archipelagos; and become enriched with soil: and in a few years they are clothed with the prurient vegetation of tropical climates. Man then takes possession: and Nature has rewarded herself for her labours: but she does not cease to extend her operations. Her work of marine creation still goes on; and the time may, one day, come, when the existence of the Pacific, as an entire ocean, will be esteemed as fabulous, as the ancient Atlantis. Islands are increasing almost every year; in size every hour. They rise in archipelagos; and archipelagos, in future ages, will associate into continents. Some have even supposed, that all marbles, limestones, and calcareous rocks, were originally formed by analogous animated beings.

II.

We may read the manner, in which Alluvial Islands? are constituted, by that in which Edmonstone Island

Vid. Flinders' Voy. to Terra Australis, ii. p. 115. Peron's Voy, to Austral Asia, p. 183.

2 For observations on the alluvial land of the Danish islands in the Baltic, and on the coast of Sleswick, vid. Jameson on Cuvier, p. 202.

has been formed. A few years since and it was not in existence. It is now situated in the upper part of the bay of Bengal; between the mouths of the Hoogly and Channel Creek. It is two miles long, and about half a mile in breadth: a mere sand-bank'; but it is rapidly acquiring a much higher character.

From the manner in which this island is proceeding, we may also form no very erroneous idea of the method, with which Nature has secured the gradual extension of her vegetable productions; and the peopling remote islands with flowers and plants. This island, having gradually accumulated by the soil of two rivers, trunks of trees, with branches containing pods and seeds, were deposited upon them. Plants, too, of various kinds were washed upon its sides. Some of these decomposed; and with the excrement of birds assisted in the formation of a fruitful soil. Seeds, too, have taken root upon the higher beach; these when afterwards in seed were scattered by the birds and winds: and some of the branches of trees cast ashore, being gradually covered with soil by succeeding tides, took root.

No human hand has yet planted one tree, shrub, flower, plant, or even seed upon this island: and yet the central part has a strong verdure, formed by the ipomea pes capra, and the salsola: and several tufts of the saccharum spontaneum have lately been observed in a flourishing condition. A few trees and plants are, also, growing up; amongst which are the manby date and morinda; a species of bean; and no inconsiderable quantity of purslane. The northern part of the beach is occupied

Vid. Journal of a Voyage to Sangor-Asiat. Journ. vii. 355.

by a large quantity of small sea crabs: and turtles are frequently seen upon the southern part.

In the north of Siberia, two islands, between the mouths of the Lena and the Indigerka, have been formed by the bones of animals, carried down, like trees, from the interior. These bones, having accumulated during the progress of ages, were at length cemented with sand and ice, till they formed two complete islands: affording a curious instance of the art, with which Nature sometimes avails herself of animal materials.

III.

Some islands have been formed by the mud of large rivers, which has gradually risen above the utmost reach of the tide. Some derive existence from the accumulation of sea weeds and trees upon rocks, but slightly buried under the waves. These substances being cast higher and higher every spring tide, become a substratum for future decompositions. Sands, blown upon each other by high winds, when left by the tide, accumulate into large banks, and alter and shift their positions at the discretion of the winds, until they acquire permanency from vegetation. The Baltic, near Kronolung, on the Swedish side, becomes shallower every year, on account of the great accumulation of sand, grass, wrack, and sea-weed.

Some islands are composed almost entirely of alluvial soil. The group at the mouth of the Orinoco were 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

Guaroüus. These aërial habitations are covered with palm-leaves; and cocoa trees furnish their inhabitants with wood for fuel; food and beverage. The Guaroüus 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'. Amsterdam Island had a similar formation; 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, cellula lava; 4th, compact lava; and 5th, glassy lava.

In

It is many ages before a coral rock becomes so deeply covered with soil, as to bear the bread-fruit tree. Amsterdam and some other islands of the Pacific, pandangs, sago-palms, casuarinas, and the Barringtonia, will grow to a great size; but the bread-fruit will not;

1 Professor Smith. Tuckey, p. 29. 4to.

2 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.