Rottenest Island is the largest in this quarter, being about eight miles in length; it contains several saline lagoons, separated from the sea, on the north-east side, by a beach composed mostly of a single species of bivalve shell. Like Buache, it is covered with an abundant and vigorous vegetation, and a small species of kangaroo is said by Freycinet to be numerous upon it. Vlaming, who first discovered it, speaks in raptures of the beauties of this island, to which, from the multitude of rats, as he thought them to be, he gave the name of the "Rats' Nest." The French call this animal the preamble ... long new.

It is not to be supposed that a hasty visit could enable the party to explore the mineralogical resources of the country. It appears, however, by a list of the soils and rock formations in Captain Stirling's report, that he brought home specimens of copper ore, of lead ore with silver, and also with arsenic, two species of magnetic iron, several varieties of granite, and chalcedony, and of limestone, with stalagmite incrustations, &c. The high cliffs of Cape Naturaliste abound with large masses of what Mr. Fraser calls "an extraordinary aggregate," containing petrifactions of bivalve and other marine shells, every particle of which was thickly incrusted with minute crystals. Here, too, he says, veins of iron of considerable thickness were seen to traverse the rock in various directions; and he speaks of the caverns formed in the minacious schistose between the granite and the limestone, as something very extraordinary. They contained rock-salt in large quantities, forming thick incrustations on every part of the surface, beautifully crystallized, and penetrating into the most compact parts of the rock. In many of these caverns were very brilliant stalactites and stalagmites of extraordinary size adhering to the nodules of granite which form their bases or floors, and which are from forty to fifty feet above the level of the sea.

In several parts of the limestone formation, mineral springs were found; one in particular was noticed within half a mile of the entrance into Swan River. It bubbled out at the base of the solid rock in a stream, whose transverse area was measured by Captain Stirling, and found to be from six to seven feet, running at the rate of three feet in a second of time. It was thermal, saline, pleasant to the taste, and some, who partook of it, attributed to it an aperient quality.

Such is the outline of a country on which the government have determined to establish a colony, and over which they have justly, and we think judiciously, appointed Captain Stirling to act as lieutenant-governor. The plan on which it is to be founded is, in our opinion, unobjectionable. It promises the most advantageous terms to qualified settlers, and deserves only to be known to ensure as many of the most respectable agriculturists as may in the first instance be desirable.

In point of climate, this colony and New South Wales may perhaps be equally salubrious, though we are disposed to think that the western aspect and the sea-breezes may preponderate in favor of the new one;—this being, probably, milder, as the western sides of all continents and large islands are, than the eastern sides, in the winter,—while the refreshing breezes cool the air in the summer. "In my opinion," says Captain Stirling, "the climate, considered with reference to health, is highly salubrious. This opinion is corroborated by that of the surgeon of the Success, who states in his report to me on the subject, that, notwithstanding the great exposure of the people to fatigue, to night air in the neighbourhood of marshy grounds, and to other causes usually productive of sickness, he had not a case upon his sick list, except for slight complaints unconnected with climate."

It likewise appears, from Captain Stirling's report, that the thermometer, in the hot months of January, February, and March, averaged, in the morning, about 60 deg.; at noon, about 78 deg.; and in the evening 65 deg. The barometer averaged about 30 deg. The weather generally fine,—some rain and showery weather, and occasionally thunder and lightning.

In geographical position it has an incalculable advantage over New South Wales. In the first place, it is not only much more conveniently situated than that colony, but is much nearer to, and has much more easy means of communication with, every part of the civilized world, the east coast of America perhaps excepted. The passages to it from England, and from the Cape of Good Hope, are shortened by nearly a month, and the return voyages still more. The voyage from it to Madras and Ceylon is little more than three weeks at all times of the year, and only a month from those places to it; while for six months in the year, namely, from November to April, inclusive, when the western monsoons prevail on the northern coast of Australia, the passage from New South Wales through Torres Strait, always dangerous, is then utterly impracticable; and that through Bass's Strait nearly so to merchant vessels, on account of the westerly winds which blow through it at all times of the year, and which generally oblige them to go round the southern extremity of Van Nieman's Land. The Success frigate left Port Jackson on the 17th of January, and did not reach Cape Leeuwin till the 2nd of February, being six weeks and two days; and Captain Stirling observes, that the only chance, by which the passage could be accomplished at all, was by carrying a constant press of sail.

One point of consideration,(says the writer of the "Hints,") in the proposed measure (although in reality of no essential importance to pecuniary success) is of considerable magnitude, as regards moral feeling and the pride of many—that is, there being no admission of convicts into the proposed colony! Without any illiberal sentiment, this is a disadvantage under which Port Jackson and Van Nieman's Land certainly suffer. Nevertheless these thriving colonies, in the course of thirty or forty years, have made surprising progress in agriculture, population, commerce and wealth. The situation of Port Jackson was the most distant from the mother country; its position was not peculiarly adapted to production or traffic with any part of the globe; therefore, the improvement can only be attributed to a favorable soil, free from the taxation of old European governments, a low fee cost, or a nominal pepper corn rent, which circumstances have not only been capable of maintaining those who adventured, but of yielding a profit for capital sufficient to induce others to pursue the same course.

In the infancy of a colony, the certain maintenance of the settlers should be well established; and it is also right to know with what facility and at what cost, an adequate supply of necessaries, comforts, and even luxuries may be obtained. Adjacent, and favorably situated to Cockburn Sound, are the Mauritius, Cape of Good Hope, Timer, Java, Sumatra, and the East Indian Presidencies.

Rice, from Java, can be obtained in five weeks, at or under 1d. per pound.