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Art. XIV. Annales de Chimic, &c. i.e. Chemical Annals. By

M. M. GUYTON, FOURCROY, &c. &c.

[Article continued. See last App.] T:

*HOSE numbers of this work, which have been last received,

abound less than usual in important facts. The first paper that occurs, however, and which occupies a considerable portion of Numbers 89* and 90, will probably be found to have considerable local interest. — It is a memeir by M. LABADIE, in answer to questions proposed by M. CHAPTAL, concerning the grapes and Tuines in the district of Bourdeaux.

The sequel of the minutes of the sitting at the Institute of Cairo indicate some attempts towards throwing light on the natural history of Egypt, and the geography of the contiguous countries. Later events have probably put an end to these undertakings.

A Dissertation on Belet's Mercurial Syrup, by B. LA GRANGE, gives a more certain process for the preparation of this syrup; which, after all, is precarious, and has no supe. riority over more common mercurials.

On the Acid of the Vetch. By M. Dispan. To obtain this acid, the writer strikes the herb with fine linen, and washes it when it is sufficiently imbibed in distilled water. The acid has no remarkable property. It bears a great resemblance to the oxalic acid; from which it is not, perhaps, perfectly distinguished.

On the colouring Matter of Vegetable Juices, and its Alteration by Tin and other Metallic substances; with a method of making Lake, of a more brilliant and solid Colour. By M. Guyton. From the experiments in this paper, the ingenious author concludes that the red colour of fruits is owing to the re-action of their own acid on their colouring matter :- that tin, in restoring the colour, only attracts from it the acid which had turned it red :-(lead, bismuth, antimony, and zinc, do the same; and iron the most quickly and completely of all); that the green, and part of the fruit, do not contain the colouring matter, but that the red part contains the portion of acid which is necessary to the production of that colour :-that if, in some vegetables, the colouring matter is so modified as to resist the acid or alkalis, it may be brought into a state to be affected by them; a fact which seems to prove them to be essentially the

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* At the conclusion of our last account of this ork, Appendix to Vol. XXVIII. p. 565, it was erroneously said, “ We finish for the present with No. 86;'--that article came down to the end of No. 88.

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same ;-that the metallic oxyds are not equally fit to attract and fix the vegetables : some, which attract them the most readily, retaining them the most feebly ;-and lastly, that the oxyd of tungsten has a decided advantage over the others.

Letter from S. FABRONI, to M. VAN Mons. The author here endeavours to prove that alcohol is not the product of the vinous fermentation, but of distillation. He thinks that this is demonstrated by an experiment, in which one hundredth part of alcohol introduced into a quantity of wine can be made to appear : whereas the wine itself, though it will afford by distillation 20 or 25 per cent. of alcohol, does not yield an atom when treated according to the same method. The method is to introduce new wine into a measure graduated into 100 parts; to add as much potash in powder, as it has been previously determined will be necessary to precipitate all the resinous colouring matter; and the alcohol which has been added will float distinctly on the alkaline solution. The author prescribes the separation of the colouring matter, merely to render the result more sensible; and he orders new wine, because the temperature of the air may determine the production of alcohol in the bottles.

Review of a Work entitled Tableau du Regne Vegetal, i. e. Picture of the Vegetable Kingdom, according to the Method of

Jussieu. By G. P. VENTENAT. 4 vols. 8vo. with 24 plates. The reviewer, M. FOURCROY, speaks in the highest terms of this introduction to botany; which is also represented as an introduction to the physiology of plants, and in some sort to rural economy.

Analysis of the Bark of the White Willow. By M. BAR'THOLDI. The white willow bark, (long since proposed in this country as a substitute for Peruvian bark, in soine cases, and superseded here by the more powerful bark of the broadleaved willow,) was employed with advantage at Colmar; and the physician to the hospital desired the writer of this paper to undertake the present analysis; which is, we think, a very common-place performance.

Memoir on the fabrication of Crayons of Paste of Sanguine, (bloodstone, hæmatites) employed for drawing. By A. F. Zomer. This is a very interesting paper. The author describes with accuracy the proper proportions, and the modes of proceeding, in order to make good crayons.

Note by A. N. SCHERER, on the Extraction of Sugar from the Beet. The plant in question is stated by M.Van Mons to be the Beta Cicla, not the B. vulgaris, Thirty-two pounds and a half of the root are said to have given three pounds and three ounces of crude sugar, of a light-brown colour; and eight pounds of refined sugar are calculated to be produced from 100 of the root, M. Achard has since published his method at full length.--- Ausfuhrliche Besübreiburg, Berlin, 1799, 8vo. pp. 63. He lays much stress on the mode of culture, and says that crude sugar can be procured at about 3d. a pound; which, if true, is intelligence of no small concern to our commercial interest, and to the slave-trade.

Account of a Work entitled the Assaryer's Msanual, by M. VAUQUELIN. - These instructions are strongly commended by the author of the article, M. B. LA GRANGE, and the well-known .character of the writer of the manual inclines us to suppose that the commendations are well bestowed.

Account of a Work by M. VAN MARUM, containing the De scription of some new er improved Apparatuses belonging to Teyler's Foundation; and of Experiments made with the Apparatuses.These apparatuses and experiments were contrived with the view of repeating, on a large scale and with rigorous exactness, certain processes already published by M. Lavoisier, as fundamental to the pneumatic theory.

Thus far had we written, and were on the point of dispatching our manuscript to the printer, when we received the NinetyFirst Number : of which the contents make ample amends for the barrenness of its two predecessors.

On the Decomposition of Muriat of Sala by Oxyd of Lead, boy M. VAUQUELIN.--The explanations of this phænomenon, hitherto given, are quite unsatisfactory. The alleged superior affinity of the oxyd is refuted by the decomposition of muriat of lead by caustic soda; and as to the carbonic acid in litharge, that has nothing to do with the phenomenon, as appears from the absolute inactivity of carbonat of lead on muriat of soda.M. VAUQUELIN has found also that the decomposition of the neutral salt is complete, when there is enough of the metallic oxyd. His experiments lead him to conclude that the litharge, which has served to decompose muriat of soda, is a muriat of lend with excess of ox7d; that the caustic alkalis do not decompose this salt, but merely dissolve it ; that it is in virtuc of the affinity of muriat of lead to this oxyd, that litharge decompounds sea-salt ;--that it is the excess of oxyd above that in ordinary muriat of lead, which communicates to the salt the property of assuming a yellow colour, on the application of heat, which does not happen to common muriat of lead ;-that it is 'this excess which renders this truriat of lead almost insoluble fa! water; and that this excess is ciissolved by nitric acid to

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form nitrát of lead, while it leaves the neutral muriat of lead undissolved.

Extract from Scherer's Journal of Chemistry.--As we mean to present our readers with an extract of all that is interesting in Scherer, we pass over this article.

Extract from a Memoir by M. VAUQUELIN on the Sap of Ve. getables.-M. VAUQUELIN examined the saps (collected at dif. ferent times from each) of the common elm (ulmus campestris), of the service (scrbus aucuparia), of the beech (fagus sylv.), of the birch (betula alda), of the carpinus sylv., and of the mulberry.' He found them to differ considerably in their composition :- but it is remarkable that the acetous acid, in greater or less proportion, is common to them all. The alkalis in the first two subjects do not exist in a state of combination with the vegetable matter, but in that of salts united with the acetous and carbonic acids; and their developement is owing to the decomposition of the acetous acid. The sap of the beech differs from that of the elm and service in containing no carbonat of lime, and in presenting acetou6 acid disengaged; as also tannin, and Gallic acid. From the sap of the birch, no white sugar could be separated ; whence the writer concludes that it contains no proper sugar.-From the sap of the mulberry, in the course of a month, a number of chrystals of nitrat! of potash were deposited.

The memoir itself is said to be sold separately, and to present a number of new facts, which the author of the extract has passed unnoticed.

Observations on the Manner in which the Mountains in the Cevennes are rendered fertile. --By M. K. CHÁPTAL. This is not,--as might be expected from such a title, occurring in such - a work, an account of chemical means of rendering soil fertile,

but of mechanical means of détaining, and causing to be deposited, the soil washed from the higher parts of the mountains. The contrivances here described consist of a number of walls built without cement, in such a direction as to cause some stagnation in the descending torrents, without stopping it entirely. Indeed, without allowing it some vent, they would be swept away; which disaster does sometimes happen.-- Such is the effect of industry exerted in this particular mode, that a surface of territory, which formerly would have been inade. quate to the support of a single family of savages, now maintains two or three hundred thousand inhabitants.

Extract from a Memoir, the first of a Series, contributing to the natural, chemical, and medical History of Human Urine; containe

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ing soine new Facts, relative to its Analysis and its spontaneous Alteration, by M.M. FOURCROY and VAUQUELIN.- This account of a truly important investigation will excite, in the highest degree, the curiosity of the medical and philosophical reader. It is shewn that the means hitherto employed have given many uncertain results, and that many errors have been committed. The materials constituting urine act on one another while the chemist is at work, and produce a liquid quite different from that which is discharged from the body. A small increase of temperature occasions, in a few moments, the formation of ammonia and carbonic acid ; and these substances are produced by the spontaneous alteration of the fluid, independently of artificial heat.

From observations on the putrid decomposition of urine, made with the view of illustrating the production of calculi, it appears that the authors have no idea of an opinion which has obtained credit in this country, and which it is of great consequence to the inquiry to establish or overturn.

We mean the doctrine of the secretion of calculous matter, in opposition to that of its de position.

Human urine contains, according to the present writers, ten principal or constant ingredients, viz, muriat of soda, muriat of ammonia, acid phosphat of lime, phosphat:of magnesia, phosphat of soda, phosphat of ammonia, uric acid, benzoic acid, jelly, and albumine, and the specific matter of urine, seisominated here urée ; of the nature of which, a particular account will be given in a future paper. In the present, it is said that to this matter the urine owes the property of becom-. ing, by spontaneous fermentation, a fluid so different from what it is when first voided, as to contain nine new ingre. dients.

Extract from the Procès-verbal of the Experiments made in two successive Years, at the Polytechnic School, on the Combustion of the Diamond. By M. GUYTON.--Much as the chemical world has been interested in the modern experiments on this prince of gems, the labours of M. GUYTON will excite not less sensation than those of his ablest predecessors. We cannot, for want of the engraving, undertake to impart to the English public a complete view of the manner of proceeding : but the result, which is more important, comes out as follows:- The diamond, in forming carbonic acid by combustion, consumes much more oxygen gas than an equal weight of charcoal does; not reckoning the residuary ashes from the charcoal. The proportion of ingredients in the acid, so far from being 0,28 of carbon and 0,72 of oxygen, turn out 17.88 of the former, and 82.12 of the latter.

Hence

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