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acids exert any sensible action upon this liquor, except the nitro-muriatic acid, and oxy-muriatic gas in a humid state. If a globule of the alcohol of sulphur be brought into contact, under water, with a globule of the oily fulminating compound, lately described to this Society by Sir H. Davy, the two globules remain in contact, side by side, without mixing, and without exerting any action upon each other; but when stirred together, they incorporate, forming a homogeneous ambercoloured globule, which does not detonate, even when exposed to ignition; and if olive oil be brought into contact with the two oils thus mixed, no detonation or other obvious effect takes place, a remarkable circumstance, of which advantage might be taken to attempt the analysis of the fulminating substance. The detonation of the fulminating compound with phosphorus, is also prevented by the presence of alcohol of sulphur ; but if the quantity of the detonating compound preponderates over that of either the olive oil or phosphorus, the mixture inflames, though without detonation.*

§ 2. Experiments to ascertain whether Hydrogen be present in the

Alcohol of Sulphur. 1. We introduced into Volta's eudiometrical tube, over mercury, some pure oxygen gas, with one drop of the oily liquor. After letting these stand together for a few minutes, an electrical charge was passed through the tube, which produced a vivid explosion. The gas was first reduced to between one

* These experiments were tried in the presence of one of us, by Mr. Wilson, Assistant to the Chemical Lectures of GUY's Hospital, who, conjointly with two other gentlemen, has lately published in NICHOLSON's Journal, many curious facts on this extraordinary compound.

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fifth and one-sixth of its volume, a circumstance which

appeared to be owing to the destruction of the volatilized portion of the liquor; for the gas soon afterwards recovered its former volume. On examining the superior part of the tube, we perceived traces of a condensed liquid. Whether this liquid was concentrated sulphuric acid, or simply a small portion of the oily liquor, remained to be determined. We repeated the experiment in the following manner.

A quantity of the oily liquor was suffered to evaporate in oxygen gas of known purity, and previously dried with muriate of lime. Some of this gas was introduced into the eudiometer, and exploded by the electrical spark. It lost between one-fifth and one-sixth of its volume; but we perceived, even then, traces of a condensed liquid in the superior part of the eudiometer. This liquid, in about a quarter of an hour, became opaque, and ultimately formed white specks, which we found to be sulphate of

mercury. No

oxygen gas remained in the tube after the explosion; but the gaseous residue consisted of sulphureous acid gas, and, as we shall see afterwards, of the carbonic acid, and the carbonic oxyd gases. This experiment having still left undetermined, whether the vestige of liquid we had observed, was or was not to be ascribed to the formation of water, we tried to decide this point by means of oxymuriatic gas, in the following manner. *

2. We caused a succession of bubbles of oxymuriatic gas, * In relating the experiments in which oxymuriatic gas (or chlorine) is concerned, we have used the old nomenclature, and have explained the phenomena according to the notions, respecting the nature of this agent, which prevailed previous to Sir H. Dave's ingenious experiments and speculations on the subject. But those who consider his views, as sufficiently established to supersede entirely the old hypothesis, may easily adapt to our statements the language which belongs to the new doctrine.

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previously dried by muriate of lime, to pass through a portion of the alcohol of sulphur, and afterwards through a quantity of distilled water, over which it was collected. The oily liquid suffered no other change than that of acquiring an orange hue. After an hour and a half the process was stopped, and the liquor was found to have absorbed a considerable quantity of the gas, which had imparted to it a peculiar and extremely strong odour. Most of the gas, however, had passed through the water, in which it had deposited a portion of the oily liquid unaltered. The water had acquired a peculiar smell, and contained, after the expulsion of the oxymuriatic gas, a little muriatic acid, with a vestige of sulphuric acid. Here again it remained doubtful, whether the production of muriatic acid was owing to the alcohol of sulphur containing hydrogen, which, by uniting with the oxygen of the oxymuriatic acid, had formed water; or whether this appearance of minute quantities of muriatic and sulphuric acid, might not be explained in some other manner. It will hereafter be seen how the last conjecture was verified; but in the mean time it was sufficiently shewn, by the experiment just related, that if the alcohol of sulphur really contain hydrogen, it must be in very small quantity, and probably from some accidental circumstance, since the greater part of the liquor remained undecompounded, and with no other alteration than the absorption of the oxymuriatic gas. In the course of a few days, however, the oil gradually lost the smell of this gas, and acquired that of the

, muriated sulphur, described by Dr. Thomson, (Sir H. Davy's sulphurane). The liquor thus treated, on being exposed to the action of water, lost its colour, and resumed its original

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characters; and this was accomplished more quickly, if the water contained some alkaline substance.

3. Into a glass receiver, full of oxymuriatic gas, we immersed some of the oily liquor previously ignited in the air; it was instantly extinguished, and appeared to undergo no change, except that of absorbing a little oxymuriatic acid, and thereby acquiring a yellow colour.

4. A portion of the oily liquor, in the state of vapour, was caused to pass through liquified muriate of silver heated to a cherry red, and to condense again into a small receiver artificially cooled; neither the liquor, nor the muriate of silver, were altered by that operation, nor did the air contained in the apparatus appear, on examination, to contain the smallest quantity of acid. This shewed that the liquor did not contain any hydrogen, since if it had, the muriate of silver would have been decomposed, the hydrogen uniting with the oxygen to form water, so as to generate muriatic acid gas ( which may be considered as a muriate of water, or more correctly a muriate of hydrogen), whilst some sulphuret of silver would have been produced

5. Though the result just related appeared sufficiently conclusive, we thought it desirable to have it confirmed by some other mode of proceeding. With this view, we heated to incipient redness, in glass tubes, various metallic oxyds, such as red oxyd of iron, black oxyd of manganese, oxyd of tin; and we caused quantities of the oily liquor in vapour to pass through these ignited oxyds. The liquor was, by that means, entirely decomposed; the metallic oxyds were converted into sulphurets, and the gases acquired a strong smell of sulphureous

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acid. But we could not, in any of our experiments, detect the least production of water, although our apparatus was so devised, as to render the smallest quantity of water conspicuous, and although we burnt, in some instances, as much as fifty or sixty grains of the liquor.

From all these experiments, we think ourselves warranted in concluding, that the alcohol of sulphur contains no hydrogen.

$ III. Experiments to ascertain the presence of Carbon in the

Alcohol of Sulphur. 1. The gaseous residue obtained from the combustion of the vapour of the alcohol of sulphur in oxygen gas, by means of Volta's eudiometer (S II. 1.), being put in contact with water, was in a great degree absorbed, and the water acquired the taste and smell of sulphureous acid. The remaining gas being agitated with lime water was partly absorbed, and produced a precipitate of carbonate of lime. The unabsorbed portion being mixed with oxygen gas, and the electrical spark passed through the mixed gases, they detonated, and the remaining elastic fluid was found to have again acquired by this detonation the property of rendering lime water turbid, and of forming carbonate of lime. The residue of the first detonation was therefore gaseous oxyd of carbon.

2. We introduced into a glass receiver, filled with pure oxygen gas, and inverted over mercury, a small glass capsule full of the oily substance, which we kindled in the air before we plunged it into the gas. It continued to burn, and we were not a little surprised to find, that the heat of this combustion was sufficiently intense to melt a pretty strong platina wire, by which the capsule was suspended, so that it fell with its

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