222 Mr. A. B. Northcote on Parathionic Acid. 



in which the carbon is to the hydrogen in the ratio of 2 : 5*22 ; 

 and thus, notwithstanding the discrepancy in the carbon, I can- 

 not but think that the substance is an isomer of sulphethylate of 

 potassium. It is not ordinary sulphethylate, nor is it isethionate. 

 Several circumstances in the foregoing account correspond with 

 the behaviour of neither of these salts ; and it is especially distinct 

 from either in fusing atl88°to 190°C, — the sulphethylate* begin- 

 ning to melt at 100°, the isethionate not fusingt until between 

 300° and 350° C. Although therefore I cannot yet consider its 

 identity established, it seems probable that it is the parathionate 

 or parasulphethylate of potassium. 



It would appear, if we carry out the ideas of the chemists who 

 have been working so largely on the propyle and amyle com- 

 pounds, and by their experiments interpret the fact of the iso- 

 merism in these lower members of the alcohol series, that we 

 must admit at least two kinds of arrangement of the atoms con- 

 stituting the group C n H 2n+1 , one of which may be crudely ex- 

 pressed by assuming the existence of C n H 2n as a separate group- 

 ing, the atom of the radical then becoming C n H 2 " . H. 



To this the very facts of the case seem to point. Wurtz J 

 obtains his isomer of iodide or bromide of amyle by simply uni- 

 ting hydriodic or hydrobromic acid with amylene. Decomposed 

 by moist oxide of silver they yield the isomer of the alcohol, 

 which by treatment with sulphuric acid, even in the cold, yields 

 no sulphamylic acid, but di- and tri-amylene. This appears to 

 speak positively to the integrity of the group C 5 H 10 throughout 

 these changes. The triple isomerism of the propyle alcohol, 

 again, appears to be intimately bound up with the mode of its 

 production; that boiling at 96° C.§ results from fermentation. 

 Friedel'sH modification, which boils at 86° to 88° C, is obtained 

 by the hydrogenation of acetone ; whilst Berthelot's from pro- 

 pylene, with which Boutlerow^f thinks his variety, obtained in 

 the complicated action of chloride of carbonyle on zincmethyle, 

 to be identical, has a boiling-point of 81° to 82° C. 



And to return to the sulphovinic series, it is found that when 

 ethylene is combined with sulphuric acid, it is the ft- sulphethy- 

 late or parathionate which is obtained. No chemist at the pre- 

 sent day would lay too much stress upon the pre-formation of a 

 molecule influencing subsequent molecular arrangement; but 

 when these instances of isomerism occur in cases in which the 

 proof of metamerism is difficult to obtain, it may be well to take 



* Gmelin (Cav. Soc.), vol. viii. p. 420. f Ibid. p. 430. 



X Repertoire de Chimie pure (1862), p. 397. 



§ Kekule, vol. i. p. 431. 



H Repertoire de Chimie pure (1862), p. 352. If Ibid. 1863, p. 593. 



