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longer in obscurity.' Another officer, of the name of Bannister, proceeded about ninety miles in a south-by-east direction, and traversed the most beautiful country he had ever seen.' Proceeding in the same direction, over a hilly region, the party thought they saw an immense mountain to the east, far above the clouds, the height of which was estimated by the surveyor at ten thousand feet. They made the coast near Cape Chatham, and, after enduring the extremes of hunger, reached King George's Sound. The effect of these discoveries on the minds of the settlers,' Captain Stirling observes, has been to remove all doubt as to the success of the colony.'

This paper is followed by another, containing a general view of the botany of the vicinity of Swan River, by Mr. Brown, the celebrated botanist. He observes, that the number of species put into his possession does not exceed one hundred and forty, and that, from materials so limited in extent, but few general observations can be hazarded on the vegetation of this portion of the south-west coast of New Holland; and that if an opinion were to be formed of the nature of the country merely from the inspection of these collections, it certainly would be extremely unfavourable as to the quality of the soil; that the opinion, however, so formed, would be necessarily modified in noticing the entire want, in the collections, of tribes, all of which must be supposed to exist, and some even in considerable proportion in the tract examined ;—in allowing for the unfavourable season when the herbarium in question was collected;-in the abundance and luxuriance of kangaroo grass ;-in the extraordinary size of some arborescent species of Banksia ;—and, lastly, in adverting to the important fact stated by Captain Stirling, namely, that the stock had not only been supported through nearly the whole of the dry season, but that most descriptions of it had even fattened, on the natural herbage of the country. We must pass over the enumeration of the different families of plants that compose the collection made on this western coast of Australia, and conclude our notice of this paper by a remarkable circumstance, which Mr. Brown had stated in the account of Captain Flinders' voyage, respecting the genus eucalyptus and the leafless acacia; two genera the most widely diffused, and by far the most extensive in this country. Speaking of these plants, he had observed,—

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They agree very generally also, though belonging to very different families, in a part of their economy, which contributes somewhat to the peculiar character of the Australian forests-namely, in their leaves, or the parts performing the functions of leaves, being vertical, or presenting their margin, and not the surface, towards the stem, both surfaces having consequently the same relation to light.

This economy, which uniformly takes place in the Acacia, is in them the consequence of the vertical dilatation of the foliaceous petiole; while in Eucalyptus, where, though very general, it is by no means universal, it proceeds from the twisting of the footstalk of the leaf.'

He now extends his observations on these genera as follows:

To this quotation it may be added that these two genera still more uniformly agree in the similarity of the opposite surfaces of their leaves. But this similarity is the indication of a more important fact-namely, the existence equally on both surfaces of the leaf of those organs, for which, as I believe them to be in general imperforated, I have adopted the name of cutaneous glands, but which by most authors are denominated pores, or stomata of the epidermis. In leaves especially of trees and shrubs, these glands are generally found on the under surface only; while among arborescent plants in a very few instances, as in several Coniferæ, they are confined to the upper surface.

In addition to the two extensive New Holland tribes here mentioned, there are many other cases in which these organs occupy both pagina; and I am inclined to think such cases more frequently occur on that continent than in any other part of the world. It is at least certain that on this microscopic character of the equal existence of cutaneous glands on both surfaces of the leaf, depends that want of lustre which is so remarkable in the forests of New Holland.'

These papers are followed by a third, containing a Description of the Natives of King George's Sound, (Swan River Colony,) and adjoining Country, by Mr. Scott Nind, and communicated by Mr. Brown.' Mr. Brown observes, that Mr. Nind, being the medical officer of the settlement established there in 1827, and living on shore till 1829, diligently availed himself of this opportunity, and the result of his observations appears to form an important contribution to the history of the race.' Those whose pursuits lead them to the study of man in his lowest and most humiliating condition will find in this article abundant food for philosophising. Its descriptions, however, are not confined to the natives, but embrace the surface of the country and its natural productions; and, combined with the two preceding papers, may help us in forming a tolerably correct estimate of a part of Australia, which, there is every ground to hope, will ere long become a flourishing English colony.

There are three interesting papers on islands that owe their existence to the action of submarine volcanos. One by Captain Smyth of the Royal Navy, on the Columbretes, volcanic rocks on the coast of Valencia in Spain; a second on the Island of Deception, one of the New Shetland Isles, by Lieutenant Kendall of the Navy; a third on the Cocos, or Keeling Islands, transmitted by Rear-Admiral Sir Edward Owen.

• Much

'Much discussion,' says Captain Smyth, has been lately directed towards Paul's, St. Santorin, and other volcanic islands, which enclose circular bays or gulfs, whence the theory of "craters of elevation" has arisen.' The most interesting part, however, of the discussion is that which is noticed by Mr. Barrow, in his short introduction to the account of Deception Island.'

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The New Shetland Isles,' he observes, are a cluster recently discovered, or, more correctly speaking, re-discovered, by Mr. Smith, a master in the Royal Navy. Dirck Gheritz, who commanded one of five ships which sailed from Rotterdam in 1598, to make a western passage to India, was separated from his companions off Cape Horn, and carried, by tempestuous weather, as far as latitude 64° S., where he discovered a high country, with mountains covered with snow, resembling the coast of Norway; and there can be no doubt that this was the group of islands in question. They seem to be a continuation of the Cordillera of the Andes, and Archipelago of Tierra del Fuego; being, for the most part, precisely of the same formation with the latter— their strata even inclining the same way. But the particular island here described is completely volcanic; and its circular crater bears a very striking resemblance to that of the Island of Amsterdam, or, as it is called by some, St. Paul, in the mid-ocean between the Cape of Good Hope and Australia.

The shape of both, too, is so like that of the lagoons which are met with in nine-tenths of the numerous low coral islands, that are scattered over the intra-tropical portions of the Pacific, as to give a colour to an opinion I was led to form many years ago, that these extraordinary fabrics, the creation of minute marine worms, are for the most part based on the edges of sub-marine volcanic craters, rising sufficiently near the surface to allow these creatures the requisite light and heat to carry on their wonderful operations, creating perpetually new islands.'-p. 62.

This creation of new islands, by effecting a change on the earth's surface, and adding to it an increase of land, brings the subject appropriately enough within the sphere of geography, though it may seem to appertain more strictly to the province of geology and natural history in general; but it is not easy to draw the precise limits that separate these sciences. Comparing these craters of elevation,' as Captain Smyth calls them, with the ridges of coral reefs that surround their inclosed lagoons, with the exception generally of an opening that communicates with the sea on one side, it is only necessary to imagine one of these reefs to be lifted up to a certain height, or these elevated islands to be depressed to the level of the reefs, and the Columbretes, Amsterdam, and Deception, would assume the precise form of so many coral islands in the one case, while a coral lagoon island would, in the other, exactly resemble an Amsterdam or Deception; and if a submarine

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force was applied to the numerous low coral islands in the Pacific, which inclose lagoons, sufficient to raise them to a certain height, we should have many thousand such islands as those above named, differing very much in size, but not materially in form. Like these too, almost all the coral reefs have their sides steep, except that where the opening is to the sea; in fact no soundings are to be had close to many of them. The inference to be drawn from this close resemblance is, that these circular islets of coral formation are based generally on the edges of submarine volcanoes, of which the lagoons are the craters. In most of them too, as a further proof, are to be found pumice stone, and other volcanic products; and as calcareous deposits are always abundant in the immediate regions of volcanoes, it is possible that these lithophytes affect such situations as being most congenial with their nature, and thus enabling them more successfully to carry on their wonderful calcareous fabrics. It is true these creatures also construct their edifices, at once their habitations and their tombs, on a grand scale, where there is no appearance of volcanic action, as, for instance, on the great barrier reef' that stretches along the eastern coast of Australia; but still it is probable they all have their bases fixed to ridges of rock, or the summit of submarine mountains. The waving lines that these kind of reefs assume, like the summit ridges of mountains as designated on maps, afford an indication of this. A remarkable one exists among those numerous coral reefs and islands which lie near and among the Seychelles; from its peculiar shape it has taken the name of the Snake Reef. Generally, however, but more especially in the Pacific, the coral formations are 'îles à lagune;' and these we conceive to be all based on volcanic ridges. Of this kind Admiral Krusenstern enumerates no less than a hundred, in a band extending between 20° and 14° of south latitude, and 134° and 149° of west longitude. Beechey visited thirty-two coral islands, where living lithophytes were gradually extending the limits of their creative labours, twenty-nine of which had lagoons in their centres, and many of these were evidently fast filling up with living rock.

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Against the opinion we have here stated, that these lagoon islands are all of volcanic origin, an objection may be taken, that in many of them, as well as in the barrier reef,' and other coral formations, there is no appearance whatever of volcanic products, no lava of any kind. But we conceive that the visible presence of volcanic products is by no means necessary to prove that volcanic action has existed. We have a fresh and striking example of this in the total absence of lava on the island which has just been thrown up between the coast of Sicily and Pantellaria; neither in the materials projected into the air, nor

in the more solid parts raised to the height of one hundred and sixty or one hundred and seventy feet, has any appearance of lava been detected. In the smell of the vapour or steam thrown out, one of the bystanders observes, there was not even the slightest symptom of its being impregnated with sulphur, and the white steam was charged only with carburetted hydrogen gas. Mr. Osborne, the surgeon of the Ganges, who was on shore, states the substance of the island to be chiefly ashes, the pulverized remains of coal, deprived of its bitumen, iron, scoriæ, and a kind of ferruginous clay -no trace whatever of lava, no terra puzzolana, no pumice stone, no shells or other marine remains, usually found at Etna and Vesuvius. A short account of this new island is inserted in the miscellaneous matter of the Journal,' and a very striking lithographic view, taken at the height of the eruption. While noticing this island, it may be mentioned as a remarkable circumstance, that on the 28th June, about a fortnight before the new island burst forth, Admiral Sir Pulteney Malcolm, in the Britannia, passed over the position nearly which it now occupies, and experienced several shocks as if the ship had struck on a sandbank; and it is further observed in the short account given in the Geographical Journal,' that a tradition is current at Malta, that a volcano burst out on the same spot about the commencement of the last century. In a chart of the Mediterranean, published some time ago, by Faden, is laid down a shoal, with only four fathoms on it, named Larmour's Breakers,' within a mile of the spot occupied by the present volcanic island. It is part of this shoal lifted up, but no melted matter had been ejected by the latest accounts. It is only, perhaps, one of the vents or safety-valves of that subterranean furnace, which heaves out its melted lava through the great chimnies of Ætna and Vesuvius. We have not heard whether either or both of these were in a state of activity at the time.

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Volcanoes are undoubtedly among the most powerful instruments by which changes of the earth's surface have been effected; but none of these changes are more remarkable, and, until of late years, less regarded, than those portions of the ocean which have been raised to the surface, or just below the surface, as we have assumed, by volcanic action, and subsequently converted into productive land, by the creative powers of animals so minute and so insignificant, as scarcely to occupy a place in the classification of the great system of Nature. We know but little of their physical economy, or of the means they employ in fabricating their gigantic piles, an operation which, for want of a better word, we designate as instinct, or, as John Hunter more forcibly expressed it, the stimulus of necessity;' by their works only we know them. That these minute gelatinous worms

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