of a fhade fometimes converts a virtue into a vice, the natural fluency of our author's periods fometimes borders on diffuseness. This remark, however, we would limit to the earlier part of' the work. He increases in vigour as his fubject ripens,

Vires acquirit eundo.'

As a fpecimen of the typographic art thefe volumes are an honour to the printer.

The work is adorned with appropriate vignettes, executed in a masterly manner, and with a portrait of Lorenzo de', Medici.

We now take our leave of this attractive performance, with fenfations fimilar to those which are experienced by the traveller, who, while eagerly feafting his fenfe of decent and fublime among the fuperb collections of the Florentine gallery, is admonifhed, by the curator, that the moments are on the wing, and that it is time to depart.

B

ART. XI. Hutton's Theory of the Earth.

[Continued from our last Number. ]

Y the prefent theory, the earth on which we dwell is reprefented as having been formed originally in horizontal ftrata, at the bottom of the ocean. Hence it fhould appear, that the land, in having been raised from the fea, and thus placed upon a higher level, had been of a different fhape and condition from that in which we find it at the prefent time. This propofition Our author confiders at large in Part II. and Volume II.

Dr. Hutton, more ftudious of perfpicuity than elegance of arrangement, with perfect propriety, recalls to the imagination of his reader the outlines of his theory on various occafions. In an introduction to Vol. II. he fays, in whatever order and difpofition the hard and folid parts of the land were, at the time of its emerging from the furface of the fea, no provifion would have then been made for conducting the rivers of the earth; therefore, the water from the heavens, moving from the fummits of the land to the fhores, must have formed for themselves those beds, or channels, in which the rivers run at prefent; beds which have fucceffively changed their places over immenfe extents of plains that have often been both deftroyed and formed again; and beds which run between the fkirts of hills that have correfpondent angles, for no other ⚫ reafon

• reason, but because the river has hollowed out its way between them.In this view of things, the form of our land must be confidered as having been determined by three different caufes, all of which have operated, more or lefs, in producing the present state of those things which we examine. First, there is a regular ftratification of the materials, from whence we know the original ftructure, fhape, and fituation, of the fubject. Secondly, there are the operations of the mineral region, fome of which have had regular effects upon the ftrata, as we find in the veins or contractions of the confolidated 'maffes; others have had more irregular effects, but which may ftill be diftinguished by means of our knowing the oriC ginal state and ftructure of those maffes. Laftly, there are < operations proper to the furface of this globe, by which the form of the habitable world may be affected; operations of which we understand both the caufes and the effects, and, therefore, of which we may form principles for judging of the past, as well as of the future. Such are the operations of the fun and atmosphere, of the wind and water, of the rivers and the tides.

It is the joint operation and refult of those three different caufes that are to be perceived in the general appearances of this earth, and not the effects of any one alone; although, in · particular parts of the earth, the operation peculiar to each of thefe may be confidered by itself, in abftracting those of the others, more or lefs. Thus, there are feveral views in which the fubject is to be examined, in order to find facts with which the refult of the theory may be compared, and by which confirmation may be procured to our reafoning, as well as expla nation of the phenomena in queftion.'

In confirmation of the theory, elevating land above the level of the fea, he makes very large quotations from M. de Sauffure, on whose works he beftows the highest commendations.M. de Sauffure has defcribed, moft accurately, not only the prefent shape and pofition of particular ftrata, but the general Thape and structure of the land from the Saleve and Jura, which are not in the Alps, to the plains of France, where the strata are generally in a more horizontal fituation. Having thus feen the ftructure of what are commonly termed the fecondary mountains, a ftructure which prevails generally in all parts of the land, at leaft in all that which is not primitive in the eftimation of naturalifts, who fuppofe a different origin of different parts, it will now be thought a most interesting view of nature, to fee the fame accurate examination of the ftructure of the earth, from thofe fecondary mountains of Geneva to the centre of the Alps, where we find fuch a variety of mountains

* mountains of different materials (whether they fhall be called 'primitive or fecondary), and where fuch opportunity is found for feeing the ftructure of those mountains. For, if we fhall find the fame principles here prevailing in the formation of thofe fuppofed primitive mountains, as are found all over the earth in general, and as are employed in fashioning or fhaping every fpecies of material, it will be allowed us to conclude, that, in this fituation of things, we have what is general in ⚫ the formation of land, notwithstanding imaginary diftinctions of certain parts which had been formed one way, and of others which are fuppofed to be operations of an oppofite nature. This queftion, therefore, will be properly decided in our author's [Sauffure's] Journey to the Alps; for, if we shall there find calcareous ftrata perfectly confolidated, as they fhould be by the extreme operation of fubterranean heat and fufion; if we find materials of every fpecies formed after the manner of ftratification; and if all thofe different ftrata, varioufly confolidated, shall be found in all pofitions, fimilar to those which we have now feen in the examination of Jura and Saleve, with this difference, that the deplacement and contortion may be more violent in thofe highly confolidated ftrata, we fhall then generalife an operation by which the prefent ftate of things muft have been produced; and, in thofe regular appearances, we fhall acknowledge the operation of an internal heat, and of an elevating power. Dr. Hutton, having reviewed M. de Sauffure's Journey, remarks, that the general result from the obfervations of that philofopher, is,

First, that there is no diftinction to be made of what is termed primary and fecondary mountains, with regard to the pofition of their ftrata.

Secondly, that in all thofe Alpine regions, the vertical pofition of ftrata prevails; and that this appearance, which feems to be as general in the Alpine regions of the globe, as it is here in the mountainous regions of the Alps, has been brought about by the fracture and flexure of those maffes, which, if properly ftrata, must have been originally extended in planes nearly horizontal.

Thirdly, that in all those accurate obfervations of a naturalift, fo well qualified for this purpofe, there appears nothing but what is perfectly confiftent with fuch a caufe as had operated by flow degrees, and foftened the bodies of rocks, at the fame time that it bended them into shapes and pofitions inconfiftent with their original formation, and often almoft diametrically oppofite to it; although there appeared to our author an infurmountable difficulty in afcribing those changes to the operation of fubterranean fire, according to the idea hitherto conceived of that agent.-It is peculiarly fatisfactory to me, and alfo, I hope, to my readers, to have the obfervations of fo able a philofopher, and fo diligent a naturalift, to offer in confirmation

of

of a theory which had been formed from appearances of the fame kind in a country fo far diftant from thofe of our author now described, as the Alps of Savoy are from thofe of Scotland.

Our theory, it must be remembered, has for principle, that all the Alpine as well as horizontal ftrata had their origin at the bottom of the fea, from the depofite of fand, gravel, calcareous and other bodies, the materials of the land which was then going into rain. It muft alfo be obferved, that all those ftrata of various materials, although originally uniform in their ftructure and appearance as a collection of ftratified materials, have acquired appearances which are often difficult to reconcile with that of their original, and is only to be understood by an examination of a feries in those objects, or that gradation which is fometimes to be perceived from the one extreme ftate to the other, that is, from their natural to their moft changed ftate.'

Inftances, or examples and proofs, of this gradation he produces from the Journey of Sauffure; after which he fays, we have here two facts extremely important with regard to the prefent theory. The one of thefe refpects the original formation. of thofe Alpine ftrata; the other, the elevation of those strata from the bottom of the fea, and particularly the erection of thofe bodies, which had been formed horizontal, to their prefent ftate, which is that of being extremely inclined. The elevation of ftrata from their original pofition, which was horizontal, is fhewn by a multitude of examples, concurring to form a general proof in a variety of ways.'

Our author, having difcuffed the proof of those mineral operations by which the horizontal ftrata, confolidated at the bottom of the fea, had been changed in their pofition, and raised into the place of land, inveftigates thofe operations, belonging to the furface of the earth, by which the confolidated and erected strata have been again diffolved, in order to serve the purposes of this world, and to defcend again into the bottom of the fea, from whence they came.

Here our ingenious and humane philofopher attaches every reader to his fubject by the following interesting observations:

Of all the natural objects of this world, the furface of the earth is that with which we are beft acquainted, and moft interested. It is here that man has the difpofal of nature fo much at his will; but here man, in difpofing of things at the pleasure of his will, muft learn, by studying nature, what will mo conduce to the fuccefs of his defign, or to the happy economy of his life. No part of this great object is indifferent to man; even on the fummits of mountains, too high for the fuftaining of vegetable life, he fees a purpose of nature in the accumulated fnow, and in majestic ftreams of the defcending ice. On every other spot of the furface of this earth, the

fyftem

fyftem of animal and vegetable life is ferved, in the productions of nature, and in the repeated multiplication of living beings which propagate their species.

But, for this great purpose of the world, the folid ftructure of this earth must be facrificed; for the fertility of our foil depends upon the loofe and incoherent ftate of its materials; and that state of our fertile foil neceffarily expofes it to the ravages of rain upon the inclined furface of the earth. In ftudying this part of the economy of nature, we may perceive the most perfect wifdom in the actual conftitution of things; for, while it is fo ordered that the folid mass of earth fhould be refolved for the purpose of vegetation, the perishable foil is as much as poffible preferved by the protection of thofe folid parts; and these folidated maffes are refolved in fo flow a manner, that nothing but the most philofophic eye, by reafoning upon a chain of facts, is able to discover it. Thus it may be concluded, that the apparent permanency of this earth is not real or abfolute; and that the fertility of its furface, like the healthy ftate of animal bodies, muft have its period, and be fucceeded by another.

The study of this fubject muft tend to enlarge the mind of man, in feeing what is paft, and in foreseeing what must come to pass in time and here is a fubject in which we find an extenfive field for inveftigation, and for pleafant fatisfaction. The hideous mountains and precipitous rocks, which are so apt to inspire horror and difcontentment in minds which look at fenfible objects only for immediate pleasure, afford matter of the most inftructive fpeculation for the philofopher, who ftudies the wisdom of nature through the medium of things. As, on the one hand, the fummit of the mountain may be fuppofed the point of abfolute fterility; fo, on the other, the fandy defert, moved by nothing but the parching winds of continents diftant from the fources of abundant rains, finishes the scale of natural fertility, which thus diminishes in the two oppofite extremes of hot and dry, of cold and wet: thus is provided an indefinite variety of foils and climates for that diverfity of living organifed bodies with which the world is provided for the use of man. But, between those two extremes, of mountains covered with perpetual fnow, and parched plains in which every living thing must perish, we find the molt pleafant fubject of contemplation, in ftudying the means employed by nature for producing the beautiful and benevolent fyftem of hills and valleys, of fertile foils and well-watered plains, of the most agreeable circumstances and proper fituations for every thing that lives, and for the preservation of an indefinite variety of organised bodies which propagate their species.

Without this philofophic view of things, the profpect of the surface of this earth is far from giving always fatisfaction or contentment to the mind of man, who is fubject to be continually displeased with that which is prefented to his view, and which, in his opinion, is not the best: in his partial views of things it is either too high or too low, too cold or too warm, too moift or too dry, too ftiff for the labour of his plough, or too loose for the growing of his corn.

8

. But,