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productum; that is, whether it previously exists in the fubftances from which it is obtained, on the addition of acid liquors; or whether it is only an extemporaneous modification of these acids. He determines in favour of the latter opinion ; but founds his determination on such grounds, as shew him to be very little conversant, or at least very ill informed, with respect to the present state of this particular branch of knowledge.

To go even so far back as Dr. Black's discoveries, with respect to the fixed air contained in lime-stone ;-the Author obferves, that Dr. Black's hypothefis on this fubject was attacked, and that of Meyer was defended, by M. Crantz : and he expresses his furprise, that none of the patrons of fixed air, have hitherto (to his knowledge) attempted to defend Dr. Black's theory, as far as they had it in their power.-Paffing over Dr. Black's powerful German second, M. Jacquin, who, in 1769, verified his experiments, and confirmed his theory by new ones; we need only to name M. Lavoisier, who, not very long afterward, fully established the credit both of the experiments and the theory, with a measure and a balance in his hand. To these two philosophers alone we may safely refer the learned Author, for an answer to the various objections which he here proposes against this new theory of fixed air,'-We shall only take notice of two of them.

When artificial nitre is made, by adding spirit of nitre to a fixed alcaline salt; the fixed air supposed to reside in the latter, is said to be all expelled by the acid: but if this were really the case, how happens it, says the Author, that when the nitrous acid has been expelled from the alcali, in the subsequent deAlagration of the nitre with charcoal; and fresh spirit of nitre is then added to the alcali deserted by it; as great an effervescence, and as large a quantity of fixed air presents itself as at first ? Whence does this fresh stock of fixed air proceed ?

It proceeds, we will inform the Author, from the particular inflammable fubstance employed to expel the nitrous acid ; whose place one of its principles immediately occupies at the very instant of the deАagration. This, however, only happens when the in Animable matter employed in the process contains fixed air : as is the case when charcoal is used. In the de. flagration, the alcali receives its fixed air, or mephitic acid from the charcoal ; in the very fame manner as it receives the vitriolic acid, when fulphur is employed in the deflagration. The Author must be too good a chemist not to know, that when tilings of iron, zinc, &c, which contain no fixed air, are used in this process; the alcali left after the detagration will not exhibit any appearance of fixed air, on the addition of spirit of nitre. This matter is fully explained towards the end of Dr. Priestley's Experiments and Observations, &c. Vol. II. p. 386.

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After denying the existence of fixed air in lime-stone, the Author endeavours to reduce the patrons of fixed air' to a dilemma, by the following reasoning. It is alleged by them, that lime owes its solubility in water, to the expulsion of its fixed air, by calcination : but magnesia, treated in the same manner, is infoluble in water. He wishes to be informed, how effects thus contrary to each other, can be produced by one and the fame cause. --But surely the inference implied in this question is highly illogical. Can any thing be more natural, than that one and the same substance may, by its presence, or absence, produce or occafion different effects in different bodies; or even in the very fame body, when the circumstances only are different?

The Author next undertakes to prove, beyond any poffibility of doubt,' that all the earth of the present terraqueous globe was derived from water, as well as that which constitutes the basis of vegetables and of animal bodies, and for this end, he endeavours to ascertain not only the poffible, but the actual transmutation of water into earth, in various instances. He not only relates the many well known experiments, in which this transmutation appears to have been actually effected; but offers likewise various other observations tending to prove the possibility of this conversion; which, however, are not of such a nature as to satisfy even the least scrupulous philosopher. It is far from our intention to treat a writer of such acknowledged merit as our Author with disrespect; but we must observe that, in numerous instances, which occur in this work, he is not very nice in his proofs; but employs any one that seems to serve the present purpose, indiscriminately ;- whether strong or weak, and whether drawn from philosophy or fcripture: for to this last the Author chuses likewise to appeal, even on philosophical questions.

According to the Author, water is converted into earth, in the various processes of vegetation, animalisation, agitation, trituration in glass mortars *, putrefaction, coagulation, by means of the sparry acid discovered by M. Scheele, and distillation. With respect to the results attending this last process, our philosophical readers may consult the particular account we gave of M.

The Author affirms that by a long continued trituration of distilled water, without intermission, in a glass mortar, he first produced veficles ; that afterwards the water became less fuid, and appeared, as it were, coagulated; and that at lalt it was changed into a light white sarth, adhering to the bottom and sides of the mortar. From only one drachm of water he declares thac he obtained about one fcrupule of this vihire carib; which he afirms 10 have found, on examination, to be of a different nature from that which can be obtained from glass.

Lavoisier's

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Lavoisier's experiments; (See Monthly Review, vol. L. Apa pendix, June, 1774. p. 544.) or Dr. Priestley's account of his trials made on water subjected to a very strong and long continued heat, in tubes hermetically sealed ; and which are contained in his late volume of Experiments and Obferuations, &c.

M. Lavoisier ascribes the earth which he procured by the diftillation, or rather cohobation, of the purest distilled water, to the abrasion of the particles of the glass vessel containing it: as he found that the pelican which he employed had lost about as much of its weight, as was equal to that of the earth procured.

The Author controverts this conclusion. He first questions the accuracy of the balance employed in this experiment. He does not think that M. Lavoisier used a sufficient degree of beat: [This objection, however, does not militate against the trials made by Dr. Priefley; who is inclined to suspect that his procesies were not continued a sufficient length of time] but his principal objection to M. Lavoisier's conclusion is, that the loss of weight observed in the pelican, at the end of the experiment, might, with cqual probability, be ascribed to the action of the fire on its external surface, as to that of the water on its inner surface : properly observing, however, that a chemical examination of the earth procured in the process, and a comparison of it with the subtle powder of glass, would best settle this point.

Having shewn that both air and earth owe their origin to water, he considers all natural bodies as consisting only of three principles;--the inflammable, the saline, and water : and then resolving the faline principle into the aqueous and the inflammable, he concludes, that the principles of all natural bodies are neither more or less than two;--earth which is undoubtedly the principle so called by Moses,' (Gen. i. ver. 1.) and the matter of light, pure. fire, celestial fire, and which is denominated cælum by Moses.' The Author endeavours to shew, how the various bodies in nature may be formed out of these two principles, in consequence of their different modifications, or the varieties introduced by figure, greater or less cohesion, &c.: but he labours still more ftrenuously to fhew, that his system has the countenance of Moses, in bis history of the creation ; where he supposes him not to have given a partial history of the creation of this earth, but of the whole visible universe. The pious Author accordingly expresses the utmost anxiety, left his philosophical and chemical principles, or his deductions from them, snould be found contrary to those of the sacred historian, and — Maximum physicum, Mosen;'-wbo, we acknowledge, was undoubtedly skilled in all the learning of the Egyptians : but how far that learning extended, with refpcct to the philosophical part of the present inquiry, we can

not,

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not, at this distance of time, determine. With somewhat less impropriety, he endeavours to establish his system concerning the formation of mountains, the deluge, &c. on the history of those events, as recorded by the facred writer.

In the preceding analysis, we have confined ourselves to matters of a general nature; as we cannot, within any reasonable compass, give even a short sketch only of the particulars of the Author's system of the formation of the earth, and its subfequent changes : as these matters are so very complicated, and so intimately connected with the Author's particular principles relative to the elements of bodies. For these the inquisitive reader must study the work itself; from which we shall only felect one particular object of the Author's investigation ; merely as being more easily detached from the rest.

This subject relates to the exuvie of foreign animals, found in those parts of the earth where such animals

do not, or cannot possibly, now live. On this point, the Author maintains an opinion, not indeed with respect to all the circumstances attending the phenomenon, fimilar to that of a late ingenious inquirer on this subject t :- viz. that they were indigenous, or lived in the very lame places, nearly, where they are now found that these places had originally a different temperature, or state of atmosphere from the present; for that the air was then, in every part of the globe, equally temperate, and propitious to animal life.

To the changes in the earth's surface, or rather in the temperature of the air, effected by the universal deluge, the Author ascribes likewise the great change produced, with respect to the age of man, immediately after that event. Some have ascribed the longevity of the Antediluvians to their temperate diet, and sober manner of living. The Author is far from adopting this idea, or even from being willing to allow that long life is to be obtained by temperance.-" The holy scriptures,' says he, intimate pretty plainly, that the Antediluvians were very far from living by rule :-[ Nil minus quan dietetice vixerunt') and that they were rather addicted, in the highest degree, to a life of pleasure and lasciviousness. We are taught by daily experience, that the most regular regimen of diet contributes very little to long life.'

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+ See Mr. Whiteburst's Inquiry, &c. or Mon:hly Review, vol. IX. January 1779, pag. 37.

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ART.

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ART. XIV. Brevis Introductio in Hiftoriam Literariam Mineralogicam, &c. A

Short Introduction to the History of the Writers on Mineralogy: with an Essay on the properest Method of forming a Mioeralogical Syliem, together with a Supplement, By John Gotsch Wallerius, Professor of Chemistry, &c. 8vo. 6 5. fewed. Upsal, &c. 1779. Imported by T. Lowndes.

HE greater part of this useful publication was compiled,

and published about ten years ago, by the Author of the preceding performance, under the title of Lucubrationum Academicarum Specimen primum. . He has changed the title of the work, because he thought proper to digest the materials intended for the promised continuation of it, into the form in which they appear in the performance, which is the subject of the preceding article.

The work itself is what the French would call a Catalogue Raisonnée, of the various systems of mineralogy, from the time of Aristotle down to the present; digested in chronological order. In this compilation, the Author not only gives the titles of the various publications respecting this science; but likewise a regular abstract of the different claffifications of mineral subftances, invented or adopted by each writer respectively; together with his own occasional observations on the particular method, or system, of each of them. His great reputation, as a systematical writer in this branch of knowledge, renders it unneceffary for us to enlarge on the utility of this mineralogical Compendium to those who are engaged in the study of foslils. To those who are more conversant in that science, it must be agreeable to see here, as it were at one view, the gradual efforts made by human ingenuity, to clear up the immense chaos which the earth contains within its bosom ; by discriminating between the numerous subjects of the mineral kingdom, and reducing them into order.--In giving a few short specimens of this performance, we shall confine ourselves to the mineralogical writers of our own times.

“ § 58. Joh. Hill, Anglus. A General Natural History of Fofils. London. 1748.” After giving, as a specimen of this work, the Author's classification of earths and stones; he observes, that his method is that of Scheuschzer and Woodward, somewhat amended; and then characterises it as · MIRIFICIS nominibus potius ONUSTAM quam ornatam.'

L68. Forsok til Mineralogie, &c. An Effay towards a System of Mineralogy; by the Nable Axel Frederic Cronstedt, Stockholm. 1758 *.

. This excellent work bas been translated into English, and was published by E. Mendes Da Coita, in 1770. See Monthly Review, vol. xlii. April 177).

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