WHEN the brilliant and extensive discoveries of Scheele, Priestley, Black, Lavoisier, and many other eminent philosophers, had thrown a blaze of light upon chemical science, and in a few years had accumulated a vast mass of information on these important subjects, a reformation in the nomenclature of the science became highly necessary to assist the further progress of chemists, by giving them a common language. This task was undertaken by Messrs. Lavoisier, Berthollet, Guyton, and Fourcroy, and the present valuable system of nomenclature was established. "It was a peculiar object with the French neologists," says the ingenious author of the work before us," to construct such expressions as might with easy changes be received by every nation where literature flourishes, or the sciences are cultivated. It was intended to be an universal language, which should not require to be translated, but merely modified according to the radical idiom and pronunciation of all that should adopt it." The extent to which the French system of nomenclature has been adopted, makes it highly desirable that the modifications which it has undergone in different languages, should fulfil the intention of the proposers, not by a servile imitation of syllables and terminations, but by transfusing the force of the original into equivalent expressions, consonant with the idiom of the language that receives it.

The object of the truly philosophical essay before us, is to point out some common mistakes in nomenclature, that occur in chemical writings; to show that the terms which we have adopted are not always the most apposite to render the French expressions; and to propose several amendments in the system, where the first principles of nomenclature have been manifestly departed from. We shall not attempt an abstract of the author's observations on these respective heads; to the general reader it would be uninteresting, and the chemist should peruse the whole treatise with attention. It will well repay his pains. The following observation shews a delicate ear and a nice judgment.

"The French and English languages have each an orthoepy peculiar to itself; and

where the differential qualities of substances are to be marked by a letter or a syllable, it is essential that the word be constructed in such a manner, that the discriminating letter, or the discriminating syllable, be the prominent feature of that word. This principle the French have observed; but so much does our language differ from theirs, that we cannot, without offending its radical pronunciation, enjoy the same advantage. They lay the accent generally upon the latter syllables; and their natural manner of speaking, sufficiently marks the distinction between nitrique and nitréux, nitrate and nitríte. On the other hand, we cannot so well render those delicate modifications of sound sensible to the car, without forcing the accent from its usual situation. For, in the common course of speaking, we should pronounce nítric, nitrous, nitrate, nitrite. This unavoidable imperfection must leave the nomenclature, in our language, inferior to its original; for the advantages we should reap, by striking at the root of the evil, would not compensate the greater merit, arising from the facility of universal communication."

The following suggestions are of importance.

"Chemistry is now in a state that demands a revision of the nomenclature. Discoveries have been made, and frequently their authors have not known how to name them. The new theory has been proved; and its principles have been found good. The object, therefore, in such a revision, would be to establish and extend the principles in a manner that would leave no room for arbitrary nomination.

For this purpose, a select number of chemists should be deputed with full powers. It would be of little consequence in what language the terms should be originally promenclature is, that it should be taken from posed; as the very first idea of the new noa dead language, in order to render it universal; and subject, not to capricious change, but to modifications founded upon reason.

"The persons chosen should be chemists; chemists in the strictest sense of the word; persons who every day find the advantages of the present nomenclature, and who every necessary that they should have read Conday feel its imperfections. It is not very dillac, or other authors, who tell us why we make use of words. If they are men of letters at the same time that they are chemists, it may, in some respects, be useful. But, above all, let them not be men of letters, ignorant of chemistry. In the nomenclature of a science, it is not the taste of the literary man, but the wants of the philoso pher, that are to be considered. The latter

is to be the creator and the regulator of the language; the former may be considered as little more than a living lexicon, and a living prosody."

The author is a very zealous partisan of the French school of chemistry. In this he will be joined by all who admire the beautiful and invaluable discoveries of Lavoisier, Berthollet, Vauquelin, and many other eminent names, but is not the following concession too great to be allowed by impartial judges?

"So far from throwing ridicule upon the French neologists, for having derived the greater part of the new terms from Rome and Athens, we must confess that they have shown great judgment, and unusual impartiality, in turning to languages so generally understood. I repeat impartiality; and I might add complaisance; for their own language being the most generally spoken of the living languages, they might have pleaded its universality in favour of any terms which it might have afforded, or which they might have proposed. This mode of proceeding might, in some very slight degree, have facilitated the study of chemistry in France; but other nations would have been excluded from the benefits of the nomenclature."

True it is, that cf all modern lan for preference, on the ground of its the French has the greatest plea guages most extensive circulation; but it is equally true, that the legitimate and acknowledged language of philosophy is the Greek or Latin, and a recogni tion of this law of nations in philosophi cal matters, prevents many jealousies and prejudices which would otherwise occur; and, moreover, in the present instance, it should not be forgotten who were the principal discoverers to whom chemistry is indebted for the facts, which alone could be the basis of the reformed nomenclature. Without recurring to the labours of Boyle, Hook, and Mayow, we may ask, whether the names of Priestley, Black, Kirwan, Cavendish, Brownrigg, and Crawford, do not present as respectable a phalanx as those of Lavoisier, Berthollet, Fourcroy, Mor veau, and Chaptal; and we fear that a faithful history of chemical discovery would reveal, in more than one instance, examples of want of candour and good faith, which ought to render us some, what cautious in giving unlimited credit to the philosophic impartiality of all the French chemists.

THE theory of the earth invented by the late Dr. Hutton, has laboured under peculiar disadvantages, on account of the singular obscurity and confusion of style, by which Dr. Hutton's own work on this subject was characterised. Professor Playfair has, therefore, performed an acceptable service to geological science, by stating, in a brief and perspicuous manner, the bases upon which the theory of his friend is founded. But it is not on this account alone that the volume before us merits regard: the greater part of it is occupied with annotations, in which difficulties are explained, new arguments are advanced, the objections of Mr. Kirwan and the other Neptunians, are replied to, and a masterly attack, on various points, is urged against the opposite theory, and some peculiar notions of Mr. Kirwan.

Dr. Hutton's first position is, that the stratified parts of the earth were formed, and are continually forming from the detritus of more ancient rocks, that the abraded particles were carried by the torrents into the rivers, and thence into the sea: when arrived in the great reservoir of water, being gently and uniformly moved by the agitation of the fluid in which they were almost suspended, they became equally diffused over the whole bottom of the ocean, and more gradually deposited stratum super strafum. All geological theories agree in

supposing the stratified minerals to have been formed by deposition in water; and as none of them explain why the matter deposited should be at one time siliceous, at another time argillaceous, at another calcareous, and at another carbonaceous, &c. we see no peculiar difficulty in admitting Dr. Hutton's representation as at least equally probable with any other. Mr. Kirwan's objec tion, that the particles brought down by the rivers are always deposited at their mouths, or on the adjacent coasts, is, in our opinion, very satisfactorily refuted by Professor P. who observes that the Maranon and Plata, and other great rivers, which carry down vast quantities of mud, do not deposit it in deltas at their mouths, and that the great rivers of China pour such large quantities of earth into the yellow sea, as to make it very shallow, and even muddy, for many leagues distance from shore.

After Dr. Hutton has thus formed his strata at the bottom of the sea, being of opinion that they cannot consolidate of themselves, he supposes that they become penetrated by the central heat, and thus acquire a stony hardness. To the hypothesis of a central heat residing in a nucleus of melted matter, it may be objected, that free caloric is so far from possessing a gravitating quality, that its constant tendency is to disper sion: there must therefore be a constant

generation of free caloric to supply the perpetual waste, more especially as Dr. H.'s theory supposes the eternal duration of the earth. Combustion, which is one of the most rapid and effectual methods of generating heat, cannot take place without the presence of oxygen and combustible matter, but the intense heat required by Dr. H.'s theory, would long ago have consumed all the oxygen that could be accumulated in the centre of the earth. Neither Dr. Hutton nor the Professor pretend to account for this perennial spring of heat, and defend their hypothesis by an appeal to facts, which they say consist in the evident marks of fusion that are exhibited in the stony crust of the earth. For our own parts, we are disposed to concede thus much to the volcanic philosophers, and to allow them their central and eternal fire, of whatever, intensity they please, provided they can hereby satisfactorily and consistently account for actual appearances.

The infusible nature of some minerals, and the ready decomposition of others by fire, is urged by Mr. Kirwan and others, against Dr. H.'s theory. If, say they, the utmost concentration of the solar rays, or the effect of a blowpipe charged with oxygen gas, cannot melt a visible portion of calc treous spar, or rock crystal, how is it conceivable that the vast mountainous tracts of limestone, and the immense quantities of quartz that occur every where, should have been brought to a fluid state? How is it possible to prevent the carbonic acid of the limestone from having escaped? To this forcible objection the only reply that has been attempted is this, that the pressure of the ocean and superincumbent strata, upon the lower ones, may be so great as to prevent the formation and escape of elastic fluids, hence the carbonat of lime may be fused without decomposition: the quartz also, under such a pressure, may be more fusible than in atmospheric air. As it is conceivable, that infinite heat and infinite pressure combined, may effect the fusion of any compound substance without the gassification of one of its ingredients, there appears no reason for rejecting the hypothesis of the consolidation of limestone strata and quartzose sand, by such means, provided it does not necessarily include direct contradictions to our experience from other

quarters: for, in researches of this kind, so great is the difficulty of obtaining satisfaction, that every theory which is consistent with itself, has a fair right to be admitted. But that this part of the Huttonian theory is inconsistent with acknowledged facts, is manifest from numberless examples. Quartz, even allowing its fusibility, is certainly much less so than felspar, schorl, mica, and chlorite, and yet in the pierre graphique of Portsoy, the quartz is impressed by the crystals of felspar, showing the former of these to have been in a soft state, while the latter was hard. Crystals of quartz are also often found penetrated by schorl and chlorite, shewing these to have been crystallized and solid while the quartz was fluid: which being directly the reverse of the order of fusibility, shows, to demonstration, that some other agent than heat was employed in liquefying the quartz. Again, seams of coal are often found penetra ted by thin lamine of quartz, and quartz crystals, therefore according to Dr. Hutton, the quartz must have been subject to a most intense fusing heat: but in this case the shale strata above and below, would have been completely liquefied, the shale being far more fusible than quartz; the schistoze texture, therefore, and all the vegetable impres sions, must have been destroyed; and though by slow cooling, according to Sir James Hall, the vitreous character may have been prevented, yet the stratum would have assumed a compact uniform appearance, and have acquired a degree of hardness very different from what we find to be actually the case.

Till these fundamental objections are answered, we do not see how Dr. Hutton's theory can be maintained; at the same time it must be allowed that the ap pearances observed in whinstone mountains, their columnar arrangement, the rupture and incurvation of the strata which are penetrated and involved by them, the irregular thickness of their beds, situated between regular and parallel strata, seem to claim for this class of mountains an igneous origin.

The most important part of the work before us, is that in which the learned Professor discusses the question of the origin of valleys, and of the immense accumulations of gravel and rounded stones that are found in various parts. Rejecting, with much good sense, the

violent hypothesis of Kirwan, Deluc, and Saussure, who choose to have recourse to the sudden agency of a grande debacle, he attributes the formation of valleys to the gradual and constant erosion of the rivers, and supposes the beds of gravel to be pudding-stone mountains in a state of decomposition, or to indicate the former course of a river.

The improper conduct of Kirwan and Deluc, in implicating theological dog mas in the discussion of a purely phi

losophical question, is very properly reprehended. The bigots of old persecuted Galileo because, by discovering that the sun was fixed, and the earth was in motion, he shewed that the bible was not to be considered as a revelation of the principles of astronomy. Modern bigots would raise the cry of infidel against Dr. Hutton and his disciples, because in their geological speculations. they refuse to consider Moses as the inspired promulgator of the Neptunian theory.

WE have derived much satisfaction from the perusal of that part of the work before us, which relates to the mineralogy of Derbyshire. Without any parade of learning, with the utmost plainness and simplicity of language, and with as much brevity as is consistent with perspicuity, Mr. Mawe has presented his readers with the result of his personal observations, made not in the usual hasty manner of superficial travellers, but collected at leisure and from repeated inspection. It is much to be wished that so laudable an example may be followed by equally able men in the other mineral districts of our island, that a country which yields to none of equal extent in the variety and value of its subterranean treasures, may be illustrated in a manner not unworthy of the advanced state of mineralogical science.

Although Derbyshire, like all other mountainous tracts, occasionally displays in the disorder, fracture and confusion of its strata, the effects of external or internal violence, yet they are, for the most part, very regularly arranged.

The uppermost stratum in Derbyshire is argillaceous grit, being an indurated mass of sand and other substances in a base of clay: it has a granular fracture, an earthy smell when breathed upon, does not effervesce with acids, and may be easily scraped by a knife: brownish red veins, occasioned by a mixture of oxyd of iron, are occasionally met with, and these parts are heavier and harder than the rest. This stratum contains, in various places, large

massive accumulations of gypsum or alabaster, which is quarried in the neighbourhood of Derby, and manufactured into columns and other ornaments, or converted by calcining into Paris plaster.

Underneath the grit is a bed of argil laceous iron ore, disposed in lamina, intermixed with nodules of various sizes: these nodules may, for the most part, be readily split, and exhibit within them very beautiful and perfect impres sions of plants, flowers, coralloids and shells. The proportion of metal obtained from this ore rarely exceeds thirty per cent.

The

The coal strata lie below the bed of iron stone, and consist of parallel bands of coal of various thickness, alternating with sandstone, tender shale, indurated clay, and bituminous schistus. beds of coal are sometimes from eight to ten feet thick, and masses of this combustible weighing three or four hundred pounds, may be easily procured Pyrites is not unfrequent in these strata, and specimens of lead ore have been occasionally found.

The bed below the coal consists of coarse siliceous grit, sometimes of the thickness of 120 yards: it is an assemblage of coarse quartzose pebbles, and exhibits several varieties. Some kinds serve as freestone for building, others are cut into mill-stones, and one, laminated with mica, is an excellent substitute for slate in roofing houses. It often contains crystallised fluor or barytes; and sometimes, though rarely, presents a little lead ore.

To this grit succeeds a bed of shale,