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VII. On a Series of Combinations derived from Pyroacetic Spirit. By 

 Robert Kane, M.D., M.R.I.A., Professor to the Royal Dublin Society 

 and to the Apothecaries Hall of Ireland, Corresponding Member of the 

 Society of Pharmacy and of the Society of Medical Chemistry of Paris, 

 Honorary Member of the Society of Apothecaries of the North of Ger- 

 many, Sfc. 



Read 16th March, and 10th April, 1837. 



A great deal of labour has been bestowed upon pyroacetic spirit by successive 

 chemists, with but imperfect results towards the development of its real nature. 

 Notwithstanding the researches of Chenevix, Macaire, Mateucchi, and many 

 others, the determination of its composition lately by Liebig and by Dumas, is 

 the only numerical fact belonging to it of which chemists are in possession. 



Pyroacetic spirit is known to be generated by heating to redness an acetate of 

 a powerful base, the acetic acid being resolved into carbonic acid and this 

 inflammable liquid ; or likewise by passing the vapour of dilute acetic acid through 

 a tube filled with coarse fragments of charcoal, and heated to dull redness. Its 

 composition is found to be per cent. 



Carbon = 62.5 

 Hydrogen = 10.2 

 Oxygen = 27.3 

 And its formulae C3 1I3 o. 



The vapour of pyroacetic spirit is found to have a density of 2.022, and the 

 results of the following experiments prove that the atom of pyroacetic spirit cor- 

 responds to four volumes of vapour. To represent the combining proportion of 

 this body we must therefore take double the ordinary formula as given above, 

 and consider Cg Hg O2 as the constituents of its atom. 



It may serve to give a clearer insight into the connexion of the following 



o 2 



