1826.J Royal Society. §91 



so coagulated. To the second paper, in which the effects on 

 the blood of heated bodies at various temperatures are described, 

 is annexed an account by Mr. Brande, of the chemical changes 

 they produce in it. 



March 9. — A paper was read, on the Analysis of Oil of Wine, 

 with Remarks on the Salts called Sulphovinates ; by Mr. H. 

 Hennell, of Apothecaries' Hall : communicated by W.T. Brande, 

 Esq. Sec. RS. The following is an abstract of this paper. 



Mr. Hennell at first supposing that the elements of oil of wine 

 were the same as those of sulphuric ether, endeavoured accord- 

 ingly to determine their relative proportions in the former sub- 

 stance, by passing its vapour over ignited peroxide of copper. 

 In this process, portions of sulphurous acid gas and sulphate of 

 copper were invariably obtained ; in attempting to ascertain the 

 origin of which, the oil of wine was heated in solution of muriate of 

 barytes, but no precipitate or even cloudiness was produced in 

 it, though litmus paper at the same time indicated the presence 

 of free acid. On concentrating the solution, however, a precipi- 

 tate of sulphate of barytes was gradually formed ; showing that 

 either the sulphuric acid was in some state of combination inter- 

 fering with its action upon tests, or that its elements existed in 

 the oil of wine in some unusual state of arrangement. From 200 

 grains of pure oil of wine, treated with solution of potash, evapo- 

 rated to dryness, and ignited, and then treated successively with 

 nitric acid and muriate of barytes, were obtained 218*3 of sul- 

 phate of barytes, indicating 74 of sulphuric acid. 



On resuming the analysis with peroxide of copper, with due 

 care, and the additional precautions suggested by the nature of 

 the substance as just pointed out, it appeared that 100 grains of 

 T)il of wine contain 53'70 of carbon, and 8'30 of hydrogen: the 

 deficiency = 38 parts beingreferable to the sulphuric acid, as showa 

 by the experiments above-mentioned. These proportions indi- 

 cate the hydrocarbon combined with the sulphuric acid to con- 

 tain an atom of each constituent ; but they do not show the 

 quantity of hydrocarbon combined with the sulphuric acid, for 

 oil of wine always holds in solution an excess of this hydrocar- 

 bon, from which it is impossible to free it. In order to deter- 

 mine, therefore, the quantity of hydrocarbon in comiwm^/o/t with 

 the sulphuric acid, some oil of wine was heated with water, and 

 precipitated carbonate of barytes was then added to it, which 

 was dissolved, with effervescence. When, hovi^ever, the solution 

 was evaporated, it soon became acid, and sulphate of barytes 

 precipitated. On treating a further quantity of oil of wine in the 

 same manner, but precipitating the barytic solution by carbonate 

 of potash, and evaporating at a temperature of ir)0° Fahr. it 

 •yierded tabular crystals, not unlike chlorate of potash, very solu- 

 ble in water and alcohol, and burning with a flame resembling 

 that of ether. These crystals were found to contain, in 100 parts, 



u2 



