bination of the elements of these substances? These questions the author proposes to chemists, assayists, and metallurgists.

From these results, M. HASSENFRATZ Concludes that the. nature of fluxes must have much influence in the disoxydation of many metallic substances; and that the distinctions among fluxes, established by the antient chemists, have not been sufficiently examined.

On Dyer's Furnaces, of a new Construction. By B. LAGRANGE. The furnace here described and figured is said to save fivesevenths of the fuel consumed according to the old construction. Those readers, who are interested in these most useful investigations, will compare the ideas of the French improvers with those of Count Rumford.

Account of a German Mineralogical Dictionary. This appears to be an useful, and almost a necessary undertaking. It is in seven languages, but is said to be defective in five out of the seven, and in the English among the rest.

Abstract of a Memoir on the Method of dyeing Cotton; and the Commerce with Scarlet spun-cotton in Greece. By M. FELIX.

Report concerning the above Memoir, by M. M. DARCET, DESMORETS, and CHAPTAL. It is well known that the art of dyeing cotton scarlet, or turkey-red, was imported into France by Greek families; that the secret by degrees tran-1 spired; and that the process was simplified by the French. The publication, therefore, of the Greek method, is at present no otherwise interesting than as it furnishes a curious document towards the history of the art of dyeing.

In the paper of M. FELIX, are some interesting passages concerning the people employed in this manufacture. having described at length the source of a litigation, which has lately proved in the highest degree detrimental to the manufactory, he thus concludes:

• For my part, I shall never forget what I saw (during my first journey) at Ambelakia, and in its environs: a numerous population, supported entirely by the fruit of its labour; and, amid the rocks. of Mount Ossa, exhibiting the affecting union of a family of brothers and friends. The fine settlements, established by the Jesuits amid the forests of Paraguay, transplanted (as it were by magic) unid the precipices and the avalanches of Tempe; the Grecian animosity mollified: the taste for vain subtleties superseded by the love for solid studies; national vanity overpowered by generous sentiments; every large and liberal idea thriving in a soil devoted for 20 centuries to slavery; the antient Grecian character re-germinating with its original energy, amid the torrents and the caverns of Pelion :-in short, all the virtues and the talents of antient Greece reviving in a corner of modern Greece.

• Industrious

Industrious Ambelakistae!. You have given me great hopes; and I have promised you brilliant destinies. Shall we both, one day, have only to regret illusions? Be sensible towards the lot of your countrymen. In the excess of their miseries, they turn their looks towards your mountains, as if happiness ought to reach them from the same quarter as civilization: their children, like the children of their early ancestors, come still to be formed in the school of your Chirons. Return them Herculeses and Achilleses.'

Analysis of Chromate of Iron, from the Bastide of la Carrade. By M. TASSAERT. The mineral here analysed is said to consist of 63.6 parts of acid of chrome, and of 36.0 of oxyd of iron, in the 100. We hope that this curious substance will not be long a stranger to our own country. A fossil into which chrome enters is said to have been lately discovered in Cornwall.

Notice of a Work entitled Chemie Optomatique, or the Art of easily acquiring that Science by aiding Discourse with Plates, Figures, and Symbols. By F. G. COURREJOLLES. This work, says its reviewer, M. Fourcroy, is the beginning of a great project for presenting the sciences in a new form; so as to produce, by mere inspection, a strong and durable impression. Although the present performance be far below the perfection which such an undertaking may acquire in time, the efforts of the author deserve the encouragement of chemists. His ideas are exact, and his plan is ingenious.

It would appear, therefore, that this work may be worthy of the notice of some of those English writers, who are so laudably engaged in providing instruction for our youth. They may be able to render it truly useful, by introducing those improvements of which it appears to stand in need.

New Researches concerning the mutual affinities of the Earths, both in the moist and dry way. By M. GUYTON. In this very curious and valuable paper, the ingenious author presents a number of experiments; whence he concludes that there exists, among all the earths, a tendency to union in both ways. This tendency, according to the degree of elective attraction, determines their precipitation from a common solvent, as also their vitreous composition; that the union of two earths, like the alloying of metals, takes place in virtue of the same law, which excludes the supposit on of a property in one of the bodies belonging to another order of substances; that, on comparing the results of these attractions with solutions by any saline substances, we should be often puzzled to say which of the earths acts on the other in the manner of alkaline or acid

The best schools in Greece are at present at Ambelakia.

solvents;

solvents; since we see lime take silex from potash, potash yield alumine and magnesia, and lime vitrify barytes, as barytes vitrifies silex; that the phænomena, in short, which may give rise to considerations of this kind, must be regarded as the effects of that contiguous attraction, which, according to its inequality in different cases, forms both the bond in natural combinations and the power of those instruments which nature employs to break them.

Historical Note relative to the Invention and the first Trials of Parachutes. By M. A. BRIEN. In this note, the idea and the actually successful employment of Parachutes is attributed to Montgolfier.

Report of M. DEYEUX respecting Notes presented by M. LEBLANC relative to Nickel. In consequence of these notes, the class of chemistry has been charged with an investigation concerning the still doubtful nature of Nickel. M. LEBLANC presumes that it is erroneous to consider this as a peculiar metal: but his experiments are not decisive.

Memoir on Areometry. By M. J. HASSENFRATZ.

Notice of a Memoir by M. FABRONI concerning the vinous, putrid, and acetous fermentations, and concerning etherification. By M. FOURCROY. Among the fourteen propositions, deduced from M. FABRONI'S memoir, the 5th is perhaps the most important. It is as follows:- Fermentation is merely the decomposition of one substance by another, as that of a carbonate by an acid, or of sugar by nitrous acid. It offers, as in the latter case, a slow effervescence. Fermentation is then an effervescence, which ought to be named vinous effervescence. To this, M. FOURCROY objects that the comparison with a carbonate, in a state of decomposition by an acid, is not exact; since the disengaged gas is an acid already formed. It is the immediate effect of a chemical attraction between three substances already composed, and retaining the nature which they previously had. Now, a ferment is not an acid; nor the fermenting matter a carbonate: the carbonic acid being formed during the fermentation. The term effervescence cannot, without confounding together heterogeneous phænomena, be applied to the action of nitrous acid in sugar; which, in part, does approach nearer to the vinous fermentation.

On the main opinion of M. FABRONI, that alcohol does not exist in avine, but arises from its decomposition, it is remarked that, though wine cannot be re-composed by adding back the alcohol to the residuum, yet this may be owing to the alteration of the substances forming that residuum, and does not completely prove

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that

that the alcohol is an entire product. If, on adding carbonate of potash to wine, that alcohol only which has been mixed with it separates, and natural (unadulterated) wine does not present this phænomenon, it may be replied, says M. FOURCROY, that it is necessary to heat wine either for a long time, or to a considerable degree, in order to extract the alcohol. The addition of potash does not suffice for extracting this substance; we cannot separate this ingredient front the others to which it is united; whereas, alcohol added to wine is not so intimately united, be ause the other principles are already saturated with it. Old wines, that give a little alcohol by this treatment, have already begun to be decompounded, and the decomposition has separated a little of their alcohol. Hence it is commonly believed that the top of bottles of good wine is more spirituous than the bottom. If M. FABRONI has observed that a heat of 14° by Reaumur is sufficient for procuring all the alcohol in wine, it must have been exposed to this temperature for a considerable time; and it is besides difficult to conceive how alcohol, which, according to Lavoisier, does not take the form of vapour but at 64°, can have been volatalized at the lower heat *. Besides, this experiment is against M. FABRONI, and exhibits. alcohol as an educt; hence, in order to reconcile it to his theory, he is obliged to announce or rather to hint that it requires a long time..

M. FOURCкOY represents wine as containing alcohol, if not so pure as after its extraction, yet as having already many of its proper characters: but so intimately combined with the other ingredients, that it is necessary, in order to obtain it apart, to decompound wine by caloric.

Conversion of soft Iron into cast Steel by the Diamond. By M. GUYTON. This curious experiment was projected by M. CLOUET; and it was performed in a manner represented by a plate attached to the present paper. The result was that some iron, heated strongly with a diamond, was converted into cast steel, the diamond disappearing. The diamond, therefore, furnished the same principle as charcoal does, since the product of the combination had the same properties as the product of the combination of soft iron and charcoal.

Experiments on the Absorption of several Gasses by Charcoal perfectly extinguished. By M. H. ROUPPE. Not only does the absorption of gasses by charcoal appear fully confirmed by the experiments, rather announced than detailed in this interesting

Perhaps M. FOUR CROY does not sufficiently attend to the effect of spontaneous evaporation, as it is called.—Rev.

paper,

paper, but it is shewn that the condensed gasses retain their properties, and exert them in some particulars more powerfully. Thus hydrogen, adhering to charcoal, forms water on being brought into contact with atmospheric or oxygen gas; and the thermometer rose when the charcoal was in contact with the air, from 52° to 100,-we presume, of Fahrenheit's scale. On placing charcoal charged with hydrogen nitrous gas, a very considerable absorption took place, and the remaining gas appeared to be azote. In like manner, charcoal charged with oxygen effected a diminution of hydrogen gas, and aqueous vapour was formed. These experiments seem capable of infinite extension, and of most useful application both in philosophical: and commercial chemistry.

From

Researches concerning Copper. By Prof. PROUSt. these ingenious researches, the professor deduces that copper is never oxydated to above 26 per cent.; or that, as to the dif ferent colours, blue and green, which have been ascribed to different degrees of oxydation of this metal, they are the sign of the combination of black oxyd with some known or unknown body.

A Review of Experiments on Milk. By M. M. PARMENTIER and DEYEUX. These experiments appeared 12 years ago in the memoirs of the Royal Academy of Medicine. They are now re-published, with important additions, in a separate work..

Observations on the Passage of the Diamond to the State of Charcoil, or of black Oxyd of Carbone, on the Disoxygenation of Sulphur by the Diamond. By M. GUYTON. This admirable experimenter, taking apparently for his motto,

"Nil actum reputans, dum quid superesset agendum," leaves no stone unturned till he has developed the exact nature of the gem in question, and has determined its relation to char coal. The curious phænomenon, however, related in this paper, was unintentionally produced. Some alumine and lime were heated with diamond, to ascertain whether the resulting glass had any effect on the precious stone: but the alumine, having, in spite of repeated edulcorations, retained some sulphuric acid, sulphuret of lime was formed, and the diamond was encrusted with black matter (charcoal): this was formed at the expence of the diamond, which had lost above a third of its weight.

Experiments on the Red Lead of Siberia. These experiments, which are translated from Crell's Annals, carry us something farther in the knowlege of the chemical habitudes of chrome..

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