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the poison of mercury on the constitution, of persons employed in silvering mirrors. Dr. Percival, comparing th« phenomena of these cases with the symptoms which arisa invariably from the absorption of lead, pronounces that the disease described by Dr. Bateman did not arise from the poison of mercury, but from the poison of Jead.

This becomes a question of high importance to the artisans engaged in silvering mirrors, for their health, sooner or later, we believe, always suffers in that employment. If, as stated by Dr. Percival, the amalgam employed is always adulterated with lead, and if that lead, not being essential to the process, be the source of the disease, the hazard of the workmen may be entirely avoided by using a purer material. The reply of Dr. Bateman will afford us the occasion to resume this subject.

XI. Reply to Mr. Field's Justification of the Apothecaries Company, in regard to the late London B harinacopacia. By Kichard Phillips.

We hav« but little inclination to enter on the ground of these criminations and recriminations. Whether the Apothecaries Company has sometimes or frequently sold imperfect preparations, or whether Mr. Phillips is always correct, and never falls into the carelessness and mistakes he charge* upon that Company, we have not the means of determining

XII. Observations on the Case of Ann Moore. By
A. Henderson, M.D.

These observations having appeared in our Journal, enlarged and corrected by the author, we shall dismiss them with the remark, that they have been the means of bringing out a complete detection of the imposition practised by Ann Moore.

MEDICAL And PHILOSOPHICAL INTELLIGENCE.

m

ROYAL SOCIETY.

On Thursday the 29th of April, the paper by Berzelius and Marcel, en the alcohol of sulphur, was continued. They obtained this substance by subliming sulphur through red-hot chaicoal in a porcelain* tube, and receiving the product in water. Thus obtained it was usually of a yellow color, from an excess of sulphur which it contained; but it was reduced to a state of purity by distilling it in a glass retort.

Thus obtained it was a colorless liquid, like water, of a pungent disagreeable taste, and a stronger swell than sulphurated hydrogen gas. It boiled at the temperature of 110° or 11.9°; and at the temperature of 53°, when the barometer stood at 30 inches, it was capable of furnishing a vapor which supported a column of mercury 7i inches high; so that when mixed with air at the common temperature it increases its bulk one-fourth. It is more volatile than ether, and produced so much cold during its evaporation that mercury was frozen. The alcohol of sulphur may be cooled down to —50* without congealing. It dissolves in alcohol and ether, depositing at the same time its excess of sulphur, if it happen to contain any. It readily dissolves sulphur. Mercury may be boifed in it without any alteration. Potassium, when heated with it, undergoes no change % but when heated in an exhausted retort filled with the vapor of alcohol of sulphur it burns with a red color, a black matter covers its surface, and on admitting water a solution of hepar salphuris is formed, inixed with charcoal.

gus.

To determine if it contained any hydrogen, ils vapor was mixed with dry oxygen gas, and detonated by electricity. No water was obtained. Oxymurialic acid gas was made to pass through it for an hour and a half, and then through water; but no muriatic ackl made its appearance, as would have been the case if hydrogen had been present in the alcohol of sulphur. It was made to pass through redhot muriate of silver; but none of the silver was reduced to the metallic state, as would have been the case it hydrogen had been present. Finally, it was made to pass over several metallic peroxides at a red heat (as red oxide of iron, black oxide of manganese). The oxides were reduced, and converted to sulpburets; but no moisture was deposited in the tube, though surrounded with ice. From all these trials it appears that alcohol of sulphur contains no hydrogen. . . . '•

On iVIay the 6th, the remainder of the paper by Berzelius and Marcet, on the alcohol of sulphur, was read. The next object was to ascertain the presence of carbon in this oily substance. When burnt in oxygen gas, the residual gas was found to contain sulphurous acid gas. This being removed, some carbonic acid gas remained, which rendered lime-water turbid, and changed pure lime into the carbonate of lime. Both these acid gases being removed, a combustible gas'remained, which detonated when mixed with oxygen gas, and was converted into carbonic acid. It was, therefore, carbonic oxide. Alcohol of sulphur being mixed with a caustic ley, with baryles-water, and with lime-water, was slowly decomposed, and a quantity of carbonic acid formed. From these and several other experiments of a similar nature, it follows demonstrably, that the alcohol of sulphur contains carbon. It is in fact a compound of carbon and sulphur, and may therefore with propriety "be called sulphuret of carbon. , s

The last object was to determine the proportion of carbon present in this compound. A great variety of methods were tried, such as burning in oxygen gas, decomposition in alkalies, &c. but none of them were found to answer. At last they succeeded, by passing the sulphuret of carbon very slowly through'a red-hot tube filled with red oxide of iron. The gaseous products were received over mercury. '- The The red oxide of iron was partly converted into sulphuret. To determine the quantity of sulphur present, it was dissolved in nitromuriaiic acid, and the whole sulphur converted into sulphuric acid. This acid was thrown down by baryles, and its quantity accurately ascertained. The gases over mercury were found to be a mixture of sulphurous acid and carbonic acid. The sulphurous acid was absorbed by brown oxide of lead, which by that means was converted into sulphate; and the additional weight being ascertained, determined the proportion of sulphurous acid present in the gas. The carbonic acid was absorbed by potash, and its weight determined in the same manner. From these data it was possible to determine the proportion of sulphur and carbon present in the alcohol of sulphur. The result was that it is a compound of 4

Sulphur 84*83

Carbon 15-17

100 or of two atoms of sulphur and one of carbon.

On Thursday the 13th of May an appendix to the preceding paper, by Professor Berzelius, was read. It consisted of the four following particulars:— , .

1. An account of the method employed in determining the proportions of carbon and sulphur in the sulphuret of carbon. The mode was to decompose a given weight of sulphuret of carbon by passing it through red-hot peroxide of iron, and receiving the products over mercury. The sulphuret of iron formed was dissolved, and the sulphur converted into sulphuric acid. The weight of sulphuric acid, of sulphurous acid, and of carbonic acid, formed, was ascertained; and from the known composition of these three substances, the proportion of carbon and sulphur was determined. Two experiments were made. In the first the loss amounted to ■$• of a per cent.; in the second to eight thousandth parts.

2. Some observations on the atomic theory. According to Mr. Dalton's theory, sulphuret of carbon is a compound of two atoms of sulphur and one of carbon. Professor Berzelius makes some remarks upon Sir H. Davy's numbers, which he has adopted in his Element* of Chemistry, and shows that they do not answer for the metallic sulphurets with the requisite simplicity. Yet if any sulphuret be treated with an acid so as to convert the metal into an oxide, the quantity of hydrogen disengaged will always indicate exactly the quantity of oxygen in the water decomposed, which would be sufficient exactly to acidify the sulphur. Berzelius thinks that unit ought to be employed to indicate an atom of oxygen, and that the weight of the other atoms should be determined by the proportion in which, they combine with oxygen.

3. On the combination of sulphuret of carbon with bases. Berzelius found that sulphuret of carbon combines with ammonia and with lime, the only bases tried. These combinations be calls qarbotulphurets. Carbo-sulphuret of ammonia is formed by putting sul» pliuret of carbon into a tube, and letting up into it ammoniacal gas as long as it will absorb it. A yellow pulverulent substance is formed,

so. 173, *t which which sublimes unaltered in close vessels, but so deliquescent that it cannot be passed from one vessel to another without absorbing moisture. If it be heated in that state, crystals of hydrosulphuret of ammonia make their appearance. Carbosulphuret of lime is formed by heating some quicklime in a tube^and causing sulphureted carbon to pass through it. The lime becomes incandescent at the time of the combination. On the outside there is formed some sulphuret of lime, which gives it a yellow color. This formation is owing to the action of the air, and is merely superficial.

4. When sulphuret of carbon is left for some weeks in contact with nitromuriatic acid, it is converted into a substance having very much the appearance and physical properties of camphor; being soluble in alcohol and oils, and insoluble in water. This substance Berzelius found to be a triple acid, composed of two atoms of muriatic acid, one atom of sulphurous acid, and one atom of carbonic, acid. He proposes to call it acidum muriaiico-sulphuroso-carbonicum.

On Thursday the 20th of May, a paper by Dr. Reid Clanney, of Sunderland, was read, on a lamp for preventing explosions in coalmines by the combustion of carbureted hydrogen gas. Dr. Clanney began by giving an historical account- of the accidents of this nature which have taken place in the neighbourhood of Sunderland within the last sevyn years; from which it appears that above 200 workmen have been suddenly killed, and move than 300 women and children left in destitute circumstances by these dreadful explosions. His lamp is extremely simple. It consists of a kind of lantern made airtight; in which a candle is kept burning. Air is constantly blown into it through water by a pair of bellows to support the combustion, and allowed to escape in the same manner through a valve. By this means no more air can explode than what is within the lantern. Thus no accident can ever happen, and the workmen will be sufficiently warned to make their escape in time.

Two circumstances, connected with this relation, deserve a more accurate investigation than they have yet received. Accidents from fire-damp, in the coal-mines in Scotland, are never known. The accidents are much more frequent in Staffordshire than about Newcastle. Do these differences depend upon the nature of the coal, or on the mode of working the mine?

Linnaan Society.—May the 4lh the remainder of Mr. Anderson's paper on different species ftf rubus was read. He terminated it with a list of various rare plants which he had observed in Britain, especially in Scotland.

Some quadrupeds from North America were exhibited to the Society by Lord Stanley.

May the 24th, at the Annual General Meeting, the following •fficers were elected :—

James Edward Smith, M.D. President.
Thomas Marsham, Esq. Treasurer.
Alexander Macleay, Esq. Secretary.
Mr. Richard Taylor, Under Secretary.

.The

The five following gentlemen were chosen into the Council:

John Barrow, Esq.

Sir Thomas Gery Cullum, Bart.

Philip Derbishire, Esq.

Mr. James Dickson.

Edward Lord Stanley.
In the room of the five following gentlemen:—

Henry Ellis, Esq.

Thomas Furly Forster, Esq.

Lieut.-Col. Thomas Hardwicke.

Claude Scott, Esq.

George Viscount Valentia. Since the last General Meeting about four British and thre« foreign members have died, and 34 new members have been elected • so that the number of fellows at present amounts to 437; the foreign members to 64, and the associates to 40.

In a paper published in Philosophical Transactions, Part II. 1812, On some Combinations of Phosphorus and Sulphur, and on some other Subjects of Chemical Inquiry, by Sir Humphrey Davy, Knt. LL.D. Sec. R. S. he has determined, 1. that phosphorus combines with two proportions of chlorine. The first of these is a limpid liquid; the second a white sublimate. To the first of these Sir H. Davy has given the name of phosphorane. It may be formed by passing the vapour of phosphorus through corrosive sublimate. It is composed of IO0 phosphorus united to 333-J- of chlorine. It dissolves phosphorus.

The sublimate, called phosphorana, is composed of 100 phosphorus united to 333£ X 2 of chlorine, or 666f.

When phosphorane is mixed with water, and slowly evaporated, crystals in the form of four-sided prisms make their appearance. These consist of phosphorous acid combined with water. Phosphorana, treated with water in the same way, forms a thick viscid substance, which consists of phosphoric acid united with water.

2. When these crystals oi kydrophosphorous acid are heated, they are converted into phosphoric acid, and a peculiar gas escapes, to which Sir Humphrey has given the name of hydrophosphoric gas.

Hydrophosphoric gas is not spontaneously combustible; but it explodes when mixed with air, and heated to a temperature rather below 212*. Its specific gravity is 0-87, that of air being 1 00: 100 cubic inches of it, under the ordinary pressure and temperature, weigh 26'53 grains. Its smell is disagreeable, but not so much so as that of phosphureted hydrogen gas: three measures of it require rather more than five measures of oxygen gas for complete combustion. When potassium is heated in it, its bulk is doubled, pliosphuret of potassium is formed, and the residual gas is hydrogen. When sulphur is heated in it, the bulk is also doubled, sulphureted hydrogen gas formed, and a compound of sulphur and phosptiorus remains. Hence the gas is a compound of 4'5 hydrogen and 22-03 phosphorus, or of 100 hydrogen and 4S9-56 phosphorus.

M2 3. When

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