289 



C H 3 S 1 n Q ** I c _ CH 2 S 

 [(C 2 H 5 ) 3 HPJ | tb -H } b -(C 2 H 5 ) 3 



The view which I am taking of the constitution of the yellow cry- 

 stals is supported by a remarkable transformation which this substance 

 undergoes under the influence of boiling water. 



I have already mentioned that this compound cannot be recrystal- 

 lized from boiling alcohol without loss. The substance is likewise 

 readily soluble in boiling water, but the solution contains no longer 

 the original compound, and no crystals are deposited either on 

 cooling or on evaporation. During ebullition the yellow compound 

 is entirely destroyed, disulphide of carbon being abundantly evolved. 

 The residuary liquid exhibits a faintly alkaline reaction, and yields 

 with acids well crystallized saline compounds. The finest of these 

 salts is the iodide which, being very soluble in boiling and only 

 sparingly soluble in cold water, may easily be obtained in long well- 

 formed needles of perfect purity. 



Analysis has proved this substance to contain 



C,H 18 PSI = [(CH.SXC.H.),*]!. 



This formula represents the iodide of a sulphomethyl-triethylphos- 

 phonium, the derivation of which from the yellow compound may be 

 readily traced. One molecule of the latter and one molecule of water 

 contain the elements of one molecule of disulphide of carbon and one 

 molecule of hydrate of sulphomethyl-triethylphosphonium, 



(CH a S) (C, H 5 ) 3 P, CS 2 + 0=CS 2 + 3 O, 



which, when treated with acids, yields the corresponding salts. 



I have not been able to eliminate the hydrate again from the iodide. 

 When treated with oxide of silver, this compound loses its iodine, but 

 not without its sulphur being likewise attacked, the last traces of 

 which are separated, however, only after protracted ebullition. Con- 

 siderable quantities of triethylphosphine are evolved during ebullition, 

 and the liquid filtered off from the black precipitate, consisting of 

 sulphide and iodide of silver mixed with metallic silver, contains the 

 hydrates of argento-triethylphosphonium and methyl-triethylphos- 

 phonium, together with the sulphates of these bases. 



