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generation is a true crystallization. The question then is reduced to this problem:-can the liquors capable of forming an organised being by crystallization be prepared only by other organised beings. This is the most common process of nature at this time, though, at the first beginning, the may have followed a different plan. It is then demonftrated that the may still employ it, and obfervation can only decide, whether the has entirely renounced it.'

The inconclufiveness of the above reasoning is too obvious to require refutation. It is only neceffary to remark, that spontaneous generation, in our author's language, is very different from the fame system of the earlier English philosophers, who poffefied equal ability, judgment, and piety. They supposed that the Almighty had originally created matter with diftinct properties, capable, in given situations, of producing beings without his immediate interpofition; nor was it, in their • opinion, at all derogatory from his honour to suppose him capable of forming a vast system, where each distinct part had a power of repairing its own defects, or its gradual decay. It is obvious, that the system of M. de la Metherie is very differ

ent,

If we were to examine some other part of this author's theory, we should find it equally defective: in that passage, particularly of his theory of the earth, for instance, where he contends, that metallic veins are coeval with the rocks in which they are contained, because if a cavity had been originally left, the weight above would have crushed the fuperincumbent part. A little reflection would have shown him, that it is not necessary a hollow should have been originally in that spot, and that the resistance from the cohesion or the arched form might have been fufficient to have preferved it. We know that there are vaft cavities in the earth, whose roofs are supported by these means.

A curious phænomenon in the natural history of the earth, which has occafioned much discussion, and continues still the subject of enquiry, is the regularly formed bafaltes. It was almost decided that it was a rock melted and crystallized in this peculiar form, when two German chemists, M. M. Werner and Wedenman, discovered a mass of basaltes refting on coal. This the editor of the Journal de Physique explains,

• In another memoir of M. Werner, which we have seen since writing the above, he mentions an argument of fomewhat more force, viz. his having observed a basaltic rock resting on clay, fand, and wache. From this alfo he concludes, that bafaltes are the production of water. But it is well known that a part of the basaltic mountain in the north of Ireland refts on a calcareous ftratum, and this proves only that bafaltes is a production, pofterior to the formation of strata in confequence of depofition from water.

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by by supposing that water is effential to the formation of basaltes, and consequently the cooling may have been too fudden to admit of the destruction of the coal. This answer we cannot admit, for a regular crystallisation is in every instance inconfiftent with rapid cooling. It is more probable, allowing the fact, which is not, however, very clearly stated, or unexceptionably supported, that lava falling in a melted state on a bed of coal, and immediately excluding the air, would affect the coal only to a certain distance, whose ashes would combine with the lower lamina of the melted mass. Or it may have happened, that the coal was formed subsequent to the basaltes, as baron Born found veins of coal in the retractions of a com mon lava.

M. Dolomieu has confidered this subject in general, instead of answering the German mineralogifts more particularly, and his memoir deserves attention, as it contains some very important obfervations on basaltes. It is introduced by a description of what has been called the Egyptian basaltes, a stone very hard, black, and greatly prized for its durable nature, and the high polish of which it was capable. It was the fubstance of many ancient works in statuary, and was brought from Ethiopia: it is styled by Strabo and Herodotus lapis Ethiopicus, and it is faid to equal iron in hardness. Many works in this stone remain, which M. Dolomieu, after a careful examination, thinks are not volcanic, with the exception of a single statue of the Villa-Borghese, covered with hieroglyphics, and formed of a black lava pierced with numerous little pores. The other black stones belong to the trapps, the schorls in mass, rarely finely grained, but often of a scaly texture, like the hornblend.

The most frequent of these black stones are granites, in which the black scaly schorl predominates so much as to give them their particular colour, while the white spar is united so fparingly, and in such minute threads, with the rest of the mafs, or in such transparent particles, as to be almost invisible. In reality, he adds, the black compact lavas resemble so closely the trapps, and the natural horn-stones, as to be indiftinguithable by external characters, and even by analysis: a careful and scientific examination of the furrounding country is often alone able to determine the difference; 'for lavas often preserve the grain, colour, texture, and other external characters of the rocks from which they are formed,' without any addidition or diminution; resembling rather the fusion of metals than any other effect of fire. It was our author's opinion in his former work, his Description of the Pontiæ Infulæ, that basaltes was the effects of the lava being cooled by water, or as he paradoxically expresses himself, the regular retraction of the prisms is the effect of the sudden cooling. The trapp, or the schorl in mass, is not, he thinks, the only earth which in cooling affumes this form, as every kind of lava is occafionally crystallised in the fame way; and earth crystallising from a watery folution, as the volcanic tufa of the Campagnia of Rome, will occafionally assume the prismatic form. On the whole, he concludes, that basaltes is a vague indeterminate term, leading to no certain conclufion; that the appellations should be prifmatic and globular lavas, while the regularity of form, though most commonly depending on a crystallzation, in consequence of fufion, may sometimes happen when the fluidity is occafioned by solution; and in neither instance is the form connected with stones of a peculiar nature.

Such are M. Dolomieu's ideas; and as he has attended closely to the effects of fire in volcanic countries, his obfervations deferve much attention. Long before the publication of his work on the Infulæ Pontiæ, we suggested the fufpicion, that the fimilarity of the trapps to the bafaltes arose from the fusion taking place in the bowels of the earth, and the little change that could in such a fituation take place in the ingredients. But that the regular crystallization can be owing to the rapid cooling, is repugnant to every other chemical fact, and it is repugnant to observation, which shows that basaltic columns are often found where water could not probably have been at the period of their formation. In short, though the different facts recorded add to our knowledge of nature, and the changes that have taken place on the globe, they scarcely improve the philofophy of this branch of natural history.

There is one part of this subject which, if well founded, will materially influence the systems of cosmogony; and it is a fact which we have formerly alluded to, viz. the reduction of some of the earths to a metallic state, which were fsupposed not to have the flightest connection with metals. We sometime ago mentioned that the calcareous earth, magnefia, and the earth of alum, had been apparently reduced, and we added foon afterwards, that the experiment was found to be fallacious. In fact, M. Klaproth afferted, that the pretended reguli were only fiderite, formed by phosphoric acid in the charcoal, joining with fome iirn on the Hessian crucible. He challenged the authors M.M. Tondi and Riprecht to the trial: they accepted the challenge; no earth was added, and no regulus was produced. M. Klaproth was seemingly defeated. Since that time, chemifts have been divided in opinion, but the best appeared to lean to the system of M. M. Tondi and Ruprecht. In this fituation we shall give the result of experiments made to a greater extent, and with a more exact attention. From a view of these, there there will be little necessity of our deciding either in favour of, or against their authenticity.

The author of the memoir, whose steps we shall follow in this account, is M. Tihausky, first lieutenant of the imperial founderies, who introduces his observations by remarking, that the apparent utility of this discovery, and the natural defire of extending his knowledge, led him to repeat M. Tondi's experiments: that chemist had himself repeated the experiments before M. Tihausky, in the public laboratoty at Vienna. The first objects of our present author's researches were the tungstein and molybdæna: but on these subjects he has added nothing new. Our principal attention must be directed to the pretended reduction of the simple earths.

The calcareous earth was put into a Heffian crucible, after being formed into a paste with linfeed oil and charcoal, covered with bones well calcined and washed, to prevent the access of air. The fire was raised tothe greatest height, and continued above half an hour. The metal obtained, in colour and brilliancy refembled platina. Its texture was granulated, and when broken appeared like steel. The line which it forme the touchstone resembled, in its grey whiteness, that made by platina. It was brittle, susceptible of a beautiful polish, and magnetic only, when broken down to a powder. Four grains and a half of metal were produced from 100 of pure earth, and its specific gravity was 6.571. M. Tondi called it parthenium.

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The metal obtained from magnesia, treated in the fame manner, was of a cinereous colour, refembling martial platina: it in other respects resembled the parthenium: from 100 grains of earth 3 of metal were only procured, of a specific gravity. equal to 7.380. This M. Tondi called aufstrum.

From the barytic earth in a very pure state, treated in the same way, a metal very fimilar to the auftrum was procured. From 100 grains of earth 4 grains of a metal of a specific gravity equal to 6.744 was produced, which was styled borbonium.

The metal obtained from earth of alum refembled steel in colour, with reddish spots. Its texture was also granulated, and it broke with the greyish colour of steel. In other respects it refembled the former metals, affording 7 grains from 100 of the earth, of the specific gravity of 6.184.

From these facts it will appear, that the new metals greatly re 'emble each other, which leads us to think that they are produced from one common substance. It is remarkable also, that no metal is produced if all communication of air is taken away; and in a larger crucible or a lefs violent fire, those portions of earth contiguous to the crucible are only reduced, Befides, all the metal procured, not magnetic, was in so minute a quantity, and with such different appearances, as plainly to indicate some other fource; and in the scoriæ glass was almost always found, resembling that which is, in other operations, procured from the fame earths. To this it may be added, that, as in all these experiments the metal in the crucible, at least on its internal substance, must be reduced, the metal found in these processes should, in every instance, be a mixed one. This led our author to a feries of experiments, in which he discovered that the crucible alone afforded iron; but when the process was conducted with powdered bone, the metal was only magnetic in its divided state. The refults then in these different experiments was truly fiderite: the appearances which we have mentioned support this resemblance, and the chemical qualities which, to shorten our account we have not noticed, are those of fiderite only. The earth of borax, also, which was reduced in M. Tondi's experiments, resembled these metals which we have described; and as calcined bones were essential to the fuccess of the process, we must suppose the fource was the fame.

There has been a more recent discovery in Cornwall of an earth apparently metallic, of which we can only give an imperfect account from a foreign Journal. It is with regret that we perceive no work in this kingdom which conveys an early account of fuch discoveries, or that our offer of configning a few pages of this Journal for the purpose has been overlooked. Mr. W. Gregor is faid to have found an earth at Menackanite in Cornwall, refembling gunpowder. It diffolves in the vitriolic acid, and the solution is yellow. If bright iron is added it affumes a reddish colour resembling amethysts. Phlogisticated alkali added to this martial amethystine solution precipitates a yellow white powder; and tincture of galls gives the same solution an orange colour. If the nitrous acid is added to the amethistine solution, and to the solution changed by the galls, the first assumes a blue colour, and the second a black. Manganese produces nearly the fame effects on these two liquors.

(To be continued occafionally.)

MONTHLY

CATALOGUE.

DIVINITY, RELIGIOUS, &c.

The Meaning which the Word Mystery bears in the New Testament, confidered and applied, in a Sermon preached to an Assembly of MiInifters. By J. Toulmin, M. Α. 8νο. Is. Johnson. 1791. IT is Mr. Toulmin's object to show, that, in the New Testament, what has been concealed, and is afterwards explained, is ufually called a mystery; and his chief conclufion is, that no incom

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