cording to the quantity of caloric with which it is penetrated; because caloric exerts a repulsive force tending to overcome the attraction of the molecules which compose the body, If the repulsive force be inferior to the attraction of the molecules, the body will be solid;-if the repulsive force and the attraction be equal, the body will be liquid; and if the former exceed the latter, the body will be aëriform. Besides these two forces, there is a third by which they are modified, namely the pressure of the atmosphere; for by this pressure the repulsive force of caloric does not so speedily vanquish the force of attraction between the molecules; and therefore, if this pressure were totally removed, we should not have any constantly liquid body: since, on the smallest augmentation of heat, exceeding the degree essential to liquidity, these bodies would be converted into vapour.Dr. CARRADORI, however, remarks that this proposition is not correct; because some substances, such as the fat or fixed oils, may be exposed to any degree of heat without being transformed into vapour, and therefore there are bodies which are constantly and not accidentally in a liquid state.

On the Oisanite, or Anatase; by M.VAUQUELIN.From the experiments made by M. VAUQUELIN, it appears that this substance is Titanium; it must therefore be removed from the class of stones, and placed in that of the metals.

A Literal Translation of Observations on the Kermes Mineral, or Red Hydro-sulphurated Oxide of Antimony; by M. CAVEZZALI, This author gives an account of several experiments, from which he deduces the following corollaries;-1. The Kermes mineral is only oxide of antimony combined with sulphurated hydrogen and a small portion of sulphur. 2. The Kermes is soluble in the alkaline hydro-sulphurets, but is insoluble in the alkalis. 3. Sulphur never combines with the alkalis without the help of the decomposition of water, by means of caloric. 4. In the dry way, the alkaline hydro sulphuret receives from the atmosphere (with which it has much affinity) the water requisite for its formation. 5. Water, both in the dry and humid way, by its decomposition, promotes the oxidation of the antimony; while its hydrogen unites with the sulphur and alkali, so as to form an alkaline hydro-sulphuret,-the only solvent of oxide of antimony. 6. The Kermes is held in solution by the excess of alkali, and it remains long in this state. The more or less rapid precipitation of the Kermes is owing to variations in the causticity of the alkalis. 7. The causes which determine the precipitation are, 1st, the excess of water in the lixivium, which, by separating the molecules of the alkali, diminish their cap city to retain the oxide of antimony; and, 2dly, the absorption of carbonic acid gas by the alkalis. 8. The

colour

colour of the Kermes is various, in consequence of the greater or less degree of oxygenation of the antimony. 9. This oxide of antimony has so great an affinity for oxygen, that it im bibes it from the atmosphere, and loses its colour. 10. This loss of colour is produced by the united action of oxygen and light. 11. The precipitation ought to be made in a place in which there is neither too great a current of air nor too much light. 12. Cold water injures the beauty of the Kermes, and therefore water moderately hot should be employed. 13. Rain water is the best for this process, because the selenite, which is commonly present in spring water, is found to be very injurious.

On an Ore of Superoxygenated Lead. According to M, VAUQUELIN's analysis, this ore is composed of,

99

There is much reason for suspecting that the lead is in the state of brown or superoxygenated oxide.

Extract from a Memoir of M. PROUST on the Species of Tanpin-It is here endeavoured to prove that there are several species of the tanning principle, or tannin, which may be obtained from catechu, dragons' blood, sumach, fustic wood, and other substances.

Analysis of the Diaspore; by M. VAUQUELIN. This stone appears to be of the nature of the Oriental ruby or sapphire; M. V. having found it to be composed of alumine, with the exception of 2 or ths of oxide of iron, which he considers as accidentally present.

700

Experiments on Charcoal; by Messrs. CLEMENT and DESORMES. This investigation was undertaken in consequence of doubts entertained by the authors, respecting the prevalent idea that charcoal contains (even after having been exposed to an intense heat) some portion of the volatile principles with which it was originally combined, and especially hydrogen. The experi ments related in this paper induce the authors to conclude that, when charcoal is well burned, it is always of a similar nature, and does not contain any perceptible quantity of hydrogen. In the course of these researches, some remarkable phænomena were observed, when sulphur was sublimed and passed over charcoal inclosed in an ignited tube of porcelain. During this process, no gas is discharged: but the substances combine together, and form a body, the properties

of

of which differ according to the circumstances of the operation in one case, the charcoal totally disappears: but, if it be in excess, then a fluid substance is formed, to which the name of carbureted sulphur has been given, (soufre carburé,) and which has many singular properties. The specific gravity of it, compared with that of water, is as 13 to 10: it is extremely volatile, and evaporates slowly at the common temperature of the atmosphere, producing a considerable degree of cold; and under the receiver of an air pump, when the barometer gauge stands at about 10 inches, it rises in the form of gas.

General Considerations on Vegetable Extracts; by M. PARMENTIER.This valuable paper may be consulted with much advantage by all pharmaceutical chemists; and we regret the impossibility of doing justice to it in the form of an abridgement.

Experiments on the Decoloration of Vegetable Liquors, by Means of Powder of Charcoal; by M. DUBURGUA.-From these experiments, it appears that charcoal may be beneficially employed to clarify vegetable juices, syrups, waters, spirituous tinctures, oils, &c. &c. &c.

Sequel to an Essay on ther; by M. DABIT.-We have here an account of some experiments from which the author attempts to prove that, during the formation of sulphuric æther, the sulphuric acid loses a certain portion of oxygen, but not sufficient to reduce it to the state of sulphureous acid. He therefore regards this as a new acid, intermediate between the sulphuric and sulphureous, and he proposes to call it oxygenated sulphureous acid. This opinion, we think, has been rather hastily formed, since the experiments can by no means be regarded as conclusive.

Experiments on the supposed Gaseous Oxide of Carbon, or Carbonous Gas; by the Society of Dutch Chemists.-From the results of their experiments, these gentlemen.conclude, 1st, that Cruikshank, Guyton, Desormes, and Clement, have been deceived by an apparent difference between this gas and carbonated hydrogen gas, and that thus they have erroneously been induced to consider it as a new species: 2dly, that the synthesis and analysis of this gaseous oxide prove that it is composed of hydrogen gas and carbon; and that therefore it can only be regarded as a particular modification of carbonated hydrogen gas 3dly, that every production of this gas is attended with. a decomposition of water; and consequently that the appearance of hydrogen gas, during the reduction of metallic oxides by charcoal, (contrary to the opinion of Dr. Priestley), is not any objection to the modern chemical doctrine.

7

Remarks

Remarks by M. FOUREROY on the preceding Memoir.-This celebrated writer here observes that the analysis made by the Dutch chemists of the gaseous oxide of carbon, which they consider only as a particulsr modification of carbonated hydrogen, does not seem to be sufficiently exact to authorize them to make such a positive assertion; and he suspects that the gas examined by them was mingled with a small portion of carbonated hydrogen, which they confounded with the former, especially as it resembles it in many respects. The experiments already made on the gaseous oxide prove that it is difficult to obtain it pure, and that it commonly is mixed with some carbonated hydrogen. M. FOURCROY intends soon to publish, in conjunction with Messrs. Vauquelin and Thenard, some experiments which he hopes will fully establish the existence of the gaseous oxide of carbon, as distinct from carbonated hydrogen gas.

Observations on the Zonic Acid; by M. THENARD.-This chemist proves by his experiments, that the substance called zoonic acid is nothing more than acetous acid, holding in solution an animal substance approaching to the state of oil; and that it is this animal matter which causes the acid to precipitate various metallic salts, especially those of mercury and of lead.

The other articles in these numbers being of little importance, or not original, have been passed over in silence, conformably to our established custom.

ART.XII. Mémoires sur l'Egypte,&c.i.e. Memoirs concerning Egypt; published during the Campaigns of General Bonaparte, in the Years 6 and 7; and also other Memoirs published during the Years 7, 8, and 9. Two vols. 8vo. Paris. 1800, 1802. Imported by De Boffe, London.

WE E have already given an abstract of the former volume of this work, from an English translation of it*; and we have now only to analyze the second part. After a short açcount of the proceedings of the Institute at Cairo, we meet with

An Analysis of the Water of the Nile, and of some Saline Waters ; by M. REGNAULT.-The water used for this analysis was taken at the point of the isle of Raoudah; and the result of the author's operations is that the water of the Nile is extremely pure, and capable of supplying every purpose of rain-water, of which Egypt is deprived; and also of distilled water, which

* See M. R. Vol. xxxiii. N. Ș. p. 131.

is

is very dear in that country, on account of the scarcity of that which is fresh. Several saline mineral waters, in Cairo and the neighbourhood, are accurately analyzed: but, as the country seems fated to relapse into a barbarous state, this kind of information is of little importance.

Report of the State of the Moristan, or Hospital of Cairo; by M. DESGENETTES.-It appears that this hospital, which is capable of receiving a hundred patients, had been shamefully neglected and mismanaged, before it engaged the attention of General Bonaparte. The details are entirely local: but there are some good general observations in a succeeding paper, by the same author, on the formation of a Hospital for the Poor of Cairo.

Continuation of Extracts from the Geography of Abd-er-Rachyd él Bakouy, containing a Description of Lower and Middle Egypt: by M. J. J. MARCEL.-These extracts, which prove that the original work resembles our geographical gazetteers, contain many curious particulars, and in some places manifest the ignorance of the modern Turks respecting the antient history of the Greeks and Persians. Short accounts are here given of Iskanderyéb (Alexandria), Rachyd (Rosetta), Damyetta, Gezyret Tanys (isle of Tanais), Faramah, Gifar, Eylah, El-A'rych Gyzeb, Mounf or Menf (Memphis), El Faycum, Fosttatt, El Qahiraħ (Cairo), &c. As a short specimen, we shall transcribe this Eastern Geographer's description of Memphis :

This antient capital of Egypt is situated on the left bank of the Nile, and was formerly a very rich and flourishing city. It was the residence of Pharaoh, before whom Moura (Moses) performed his miracles, and whom God drowned in the Babbar Qolzoum (Red Sea). Some assert that this was the first city built in Egypt after the Deluge. Four immense canals of the size of rivers passed through it, and met in the middle of a vast square in the front of Pharaoh's palace. Here this prince established his royal throne, and here he exclaimed in his pride, "Four rivers roll beneath my feet." Memphis continued to be the seat of power, and the residence of science and the arts, till the time of Alexander, who built the city of Alexandria. It is now entirely destroyed: but there are still some ruins which attest its former grandeur and magnificence.'

The French editor has enriched his extracts from the Oriental geographer with some valuable notes, to which our limits will not allow us to do justice. At the word Mousa in the above account, we are referred to the bottom of the page, where considerable additions are made to the original text respecting the eastern history of Moses, and where we read as follows:

• Mousa ébn Amram, êbn Qâhât, êbn Lâoûy, êbn Ya qoub, (Moses the son of Amram, the son of Qahat, the son of Levi, the son of

Jacob,)