Imatges de pàgina

• This is a very positive decision against the opinion of a man whose talents and knowledge of oriental learning were such as to give to his opinions on such subjects the greatest weight. If the statements and reasonings of sir George Staunton be accurate, the Chinese empire must have subsisted at least 3000 years before the Christian era ; for he says expressly, that many ages must have elapsed before the commencement of that cycle, which, according to him, commenced 2277 years before the birth of Christ. But surely Confucius was as well acquainted with the ancient annals of his own country, and the credibility which is due to them, as any man of the present age, whether Chinese or European ; and we have seen, that he considered none of them as authentic which relate events previous to the eleventh century before our era. Even this is by much too early a period at which to rely upon them with implicit confidence, if it be true, as sir George informs us, that the transactions of the empire have been regularly recorded only from about three centuries before the birth of Christ. With respect to the cycle, there is every probability that it was derived from India, where we know that astronomy has been cultivated as a science from time immemorial, and where, we have shown in another place, that the commencement of the cycle was actually antedated. (See Philosophy, No.9. Encyl.) We have therefore no hesitation in preferring sir William Jones's opinion of the origin of the Chinese empire to sir George Staunton's; not merely because we believe the former of these gentlemen to have been more conversant than the latter with Chinese literature, but because we think his reasoning more consistent with itself, and his conclusion more consonant to that outline of chronology, which, as he observes, has been so correctly traced for the last 2000 years, that we must be hardy sceptics to call it in question.' Vol.i. P.418.

• To sir William Jones's derivation of the Chinese from the Hindoos, the state of their written language may occur as an objection ; for since it is certain that alphabetical characters were in use. among the Hindoos before the period at which he places the emigration of the Chinas, how, it may be asked, came these people to drop the mode of writing practised by their ancestors, and to adopt another so very inconvenient as that which the Chinese have used from the foundation of their empire? The force of this objection, however, will vanish, when it is remembered that the Chinas were of the military cast ; that they had gradually abandoned the ordinances of the Veda, and were in consequence degraded; and that they rambled from their native country in small bodies. We do not know that the military cast among the Hindoos was ever much devoted to letters; there is the greatest reason to believe that a degraded cast would neglect them; and it is certain that small bodies of men, wandering in deserts, would have their time and their attention completely occupied in providing for the day that was passing over them, That the Chinas should have forgotten the alphabetical characters of the Hindoos is therefore so far from being an objection to sir Wil. liam Jones's account of their descent from that people, that it is the natural consequence of the manner in which he says they rambled

from Hindostan to the northern provinces of what now constitutes the Chinese empire.' Vol. i. P. 419.

The additions to the article church' relate to the Greek church; and a very satisfactory account of its rites and ceremonies is inserted. On the cultivation of coffee' we have some good accounts from different works published since the æra of the Encyclopædia ; and even of the humble trade of a

cooper' we have information which few would expect, and which to many will be new. The remarks on accidental colours' are valuable ; but, on the subject of 'contagion, the editor seems to trust too implicitly to Dr. C. Smyth's mode of fumigation. We remember remarking, that Dr. Duncan did not give sufficient attention to the opposite methods. The author observes that we know little of contagion. It is indeed true : but we know pretty well how, in the greater number of instances, to avoid it.

We have already extended our article too far; and it may frighten our readers to reflect that we have only finished the letter C. We trust, however, that we have laid the foundation for more quick dispatch in future, and hope that our farther remarks will not proceed beyond another article. We may, like the compilers of the Encyclopædia, miscalculate; but we are certain that we shall not err in so great a degree.

. (To be continued.) .

ART. IV.-The Natural History of Volcanoes : including Submarine

Volcanoes, and other analogous Phenomena. By the Abbé Ordinaire, formerly Canon of St. Amable at Riom in Auvergne. Translated froin the original French Manuscript, by R. C. Dalias, Esq. 8vo. 85. Boards. Cadell and Davies. 1801.

I HE fate of volcanoes, as philosophical agents, has been singular. For ages they astonished and terrified, and were considered as the most dreadful and destructive powers : in turn they became in our systems the great means of reproduction, the sources of fertility, the causes which divided the waters from the waters, and made the dry land appear. In the hands of the geologist they were agents peculiarly convenient and manageable; for he could place them in any region, and produce from them any change. Sound observation has however corrected the error in each extreme. Volcanoes are isolated mountains, not comparatively numerous, nor extensive in their advantages or their devastations. Many of their fancied vestiges we have discovered to be of a different origin; and their intense fires have been found of less temperature than even the most modest philosopher formerly ventured to suspect. At a period,

lights; and to the numhe abbé cernierala wern inquirific

an mind, or the cad withon, or abwhen we th which e bwill not in and the ever doctures of antage; an error onger

therefore, when philosophy has calmed the ardor with which we surveyed these stupendous phænomena—when we no longer regard them with stupid admiration, or abject terror-their • Natural History' may be read with advantage ; and facts may. triumph over theory, or the structures of a fertile imagination. The human mind, however, does not soon step down from its ardent flights; and the period is yet at some distance when fancy will not add to the number and increase the power of these burning projections. The abbé Ordinaire's researches have been extensive, and his work is in general a valuable one: yet he is deficient in some points that more modern inquiries might have supplied; and we are surprised that the scientific investigations of Kirwan, and the later philosophical observations of Spallanzani, escaped him. On the whole, indeed, this work is in some measure flimsy and superficial; but it contains some facts, of importance, and a collection of numerous observations not before brought together in so regular and pleasing a form,

The abbé describes volcanic mountains, and the inflammable substances which may feed their fires. He supposes that the existence of many apertures shows that the mountain will soon cease to be volcanic : but for this he offers no very satisfactory reason. He speaks of subterraneous fires where there are no explosions; but no where distinguishes with accuracy the causes of the explosion. His enumeration of those internal fires not attended by explosionis is very full: that from M. Pallas we should have transcribed, had not the work been before us, both in the French and English versions. The abbé seems to support the theory of central fires, and to suppose that commotions in the earth may arise from these; so that in many places a volcano which might serve as a spiraculum would be beneficial. The remedy is however a very dangerous one; and we believe it may be greatly doubted, whether the causes are so nearly the same as the author, with others, has supposed; and the existence of central fires to any extent is very improbable.

The formation of mountains, M, Ordinaire contends with great justice, is not owing to volcanoes ; for even the most sin. gular volcanoes known at present were mountains before they exploded. In this disquisition he would have found an able assistant in Spallanzani. With equal reason, the opinion that all volcanoes are formed at the bottom of the ocean, and the mountains raised by their power, is rejected by our author. Why, however, volcanoes should be found only in the highest mountains, it is nut easy to explain. The following reasons require the support of facts; yet they are as plausible as most others.

Mountains, like all the other productions of nature, have a regular conformity of parts: the dimensions of their mass are in due proportion: I mean that we may always estimate the width of the sides, and the depth of the base, by the height to which the head of a mountain rises on the globe. The exceptions to this rule, for there are some, are very few in number.

• We may add, that, of course, all the internal properties of which a concurrence is necessary to the forming of a volcano, such as fissures, caverns, a variety and abundance of inflammable matter, and a quantity of air and water, all in that case preserve similar pro. portions.

. According to these plain observations, we shall not find in a mountain of an inferior order either bulk sufficient to contain and put in action what is necessary to produce a volcano of the first kind, which I have just mentioned ; or depth enough for its base to reach, and still less for its sides to attract, the interior fires, commonly called central, and give existence to a volcano of the second kind.

• But we can conceive without difficulty that the summit of a very high mountain, which in its descent takes an extension always increasing, probably down to its extreme internal base, may become a volcano either way. Etna extends itself nearly beneath the whole island of Sicily: what a prodigious lateral expansion, what dimensions at its base must it have when it reaches its lowest internal foundation! As to its depth, we must suppose it very great ; but where shall we presume that it stops ?

• If we consider the peak of Teneriffe, only from its summit to the level of the Atlantic ocean, how is it expanded even in that descent! Yet that is but its apparent base on the surface of the globe. Could we follow it to its interior foundation, how should we be astonished at its extent and depth!

• It is easy to conceive that nature may either convert such prodigious masses into formidable arsenals, or employ them as firepumps in throwing out the subterranean fires, in order to relieve the bowels of the earth, and prevent a confusion over the whole surface of it.

• I admit that all volcanoes are not so high as Etna, or the peak of Teneriffe ; but we may consider these two as holding nearly the middle point on the scale of volcanic mountains. Many volcanoes are of their height: they are about a third lower than the highest, and certainly very few are a third lower than they are.? P.68.

Our author supposes that the mountains in the moon are higher than those on the earth, in a greater proportion than has been conceived; because the estimation of the latter commences from the level of the sea; while those of the moon have their measure commenced from their immediate bases : and he thinks that the volcanoes of the moon are in like manner considerable. He is somewhat at a loss to explain why submarine volcanoes should have no apparent elevation ; but we know little of these, except

when connected with burning mountains on an adjacent island, · and cannot easily in any case measure their elevation. The sea

is undoubtedly much deeper than has been supposed; for M. de la Place has shown that we must admit a hitherto unsuspected

depth, to be able to account for the phænomena of the tides from attraction.

The abbé next enumerates the many islands rendered unin. habitable by their volcanoes, and particularly notices the state of Iceland. The heat of simply hot water springs is, he thinks, owing to subterraneous fires, as well as the heat of all others which contain neither iron nor sulphur. It is singular that he should have overlooked the great heat of the Gieser fountain, which must be more than that of boiling water. This great degree it is compelled to bear from the compression, as it retains that heat after having been raised so high in the air. Kamtschatka is in the same latitude with Iceland, but in opposite longitades, and equally subject to volcanic fires. Our author considers this as merely accidental ; since the fires of volcanoes are, he thinks, in the external “coats' of the earth. The abbé is of opinion that volcanoes render the neighbouring districts fruitful and healthy. This however has never been proved : they are not 'unusually sickly or infertile during the remission of the volcanic convulsions, nor are they peculiarly fruitful and healthy after them.

Our author treats next of the cause of these commotions ; and, though he speaks much of oils, bitumens, fermentations, &c. he rests the chief action on its true foundation-the power, ful expansion of water when, by heat, it becomes steam. Here too Spallanzani, and even sir William Hamilton, would have assisted him. Various circumstances of an eruption are noticed in the following chapters. A description of such a phænomenon we shall select,

« Let the reader figure to himself Vesuvius near four thousand feet high, Etna which is more than twelve thousand, Pichinca which is fifteen thousand, Cotopaxis or Antisana, which are eighteen thousand; or, in fine, the insular volcano we have already mentioned, which was thought to exceed Chinboraço, and which, were it only equal to it, would still be nineteen thousand three hundred and ninety-two feet in height; let him imagine a column of fire of three or four miles in circumference, and sometimes more, whose height is more than double that of the mountain, rising from it with a thun. dering noise greater than that of all the cannon in the world discharged together. It seems as if it would set the sky on fire: lightnings flash from it. The dazzling brightness of its fire could not be endured by the eye, did not immense spiral clouds of smoke mode. rate its fierceness at intervals. These spread through the atmosphere, which they thicken; the whole horizon is covered with darkness; and at length nothing is to be seen but the burning summit of the mountain and the wonderful column of fire.

• Its height, bulk, and explosion, result from the confinement in which the air had been kept within the volcano. Rarefied to the highest degree, forced on by the increasing heat of the immense pit, and pressed more and more by the prodigious fermentation of the

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