1868.] 



of Et hylic Mustard-oil. 



69 



mercuric chloride, the precipitate which remains after the ethylic mus- 

 tard-oil is separated by distillation, neither dissolves in boiling water nor 

 in boiling alcohol, if this precipitate were pure mercaptide of mercury, 

 it should be crystallizable from boiling alcohol. Probably it is a double 

 compound of mercaptide and chloride ; at all events, I have established 

 by experiment that mercaptide and chloride of mercury unite to form a 

 compound perfectly insoluble both in water and alcohol, even on boiling. 



Triethylamine also unites with bisulphide of carbon : but this com- 

 pound, as might have been expected, yields no longer any mustard-oil. 



Ultimately, as regards the ammonia, which invariably occurs in the crude 

 mixture of the ethyl-bases, its presence rather increases than diminishes the 

 quantity of mustard-oil which is formed. This ammonia remains in the 

 residue in the form of a salt, together with salts of ethylamine, diethyl- 

 amine, and triethylamine ; and a corresponding quantity of the primary and 

 secondary ethyl-bases is converted into mustard- oil, the yield of which 

 may thus be very considerably augmented. 



The mercuric salts also attack ethylic mustard-oil, although much less 

 easily and rapidly than nitrate of silver. A large excess of chloride of mer- 

 cury, however, should be avoided. If the ethylamine be prepared from iodide 

 of ethyl, it is convenient to employ the mercury salt and the mixture of bases 

 in such proportions that 1 molecule of mercuric chloride reacts upon the 

 bases generated by means of 2 molecules of iodide of ethyl. 



In an experiment carried out upon rather a large scale a quantity of 

 ethylic mustard-oil was obtained amounting to from 60 to 70 per cent, of 

 the theoretical proportion which might have been expected from the 

 weight of iodide of ethyl employed. 



Ethylic Mustard-oil. 



As to the physical properties of ethylic mustard-oil, I have not to add 

 anything to what I have formerly stated, except a determination of the 

 gas-volume weight, which was taken in the vacuum of the barometer at the 

 temperature of 185° (in the vapour of boiling aniline). 



Referred to hvdrogen. Referred to air. 



Theory. Experiment. Theory. Experiment. 

 Gas-volume weight 43'5 4375 3'02 3*03 



"When operating with the isomeric sulphocyanide of ethyl, the following 

 numbers were obtained : — 



Referred to hydrogen. Referred to air. 



Theory. Experiment. Theory. Experiment. 

 Gas-volume weight of sulphocyanide 1 



of ethyl (determined in the vapour L 43'5 42-84 3*02 2*98 



of boiling water) J 



