186 Drs. Letts and Collie on the Salts of 



ance, and by the formation of the characteristic compound 

 with iodide of zinc. The gas, when passed through solution 

 of hydrate of barium, gave no turbidity. It was not affected 

 by bromine, and burnt with a luminous flame. The theoretical 

 yield of ethane from the quantity of base operated upon is 

 822 cubic centim. — a quantity which is sufficiently near to 

 that found to prove that the base decomposes wholly in the 

 manner indicated by Hofmann and Cahours. 



We have already shown that the hydrate of tetrabenzyl- 

 phosphonium suffers a similar decomposition under the influ- 

 ence of heat, * 



(C 7 H 7 ) J>OH = (C 7 H 7 ) 3 PO + C 7 H 8 . 



Action of Heat on the Sulphate of the Tetrethylphosphonium. 



25 grms. of pure iodide of tetrethylphosphonium were 

 dissolved in water and converted into the corresponding 

 sulphate by the action of sulphate of silver. The solution 

 was filtered and treated with hydrochloric acid and sulphur- 

 retted hydrogen to remove the dissolved silver. It was again 

 filtered and concentrated to a small bulk over the water-bath. 

 During the concentration, a strong smell of triethylphosphine 

 became manifest, showing that decomposition had commenced, 

 and this increased as the concentration was proceeded with ; 

 and even when the solution was removed from the water-bath 

 and placed in vacuo over phosphoric anhydride, the smell of 

 triethylphosphine was still apparent. 



After remaining under these conditions for some time the 

 solution solidified to a highly deliquescent crystalline mass, 

 which could not be obtained in a fit state for analysis owing to 

 its hygroscopic nature. It was accordingly transferred to a 

 distilling flask and heated in an oil-bath. In a short time 

 gas was evolved whilst a colourless liquid distilled, and there 

 remained behind in the flask a charred mass. The distillate 

 solidified on cooling, and from its appearance we were led to 

 the conclusion that it contained sulphide of triethylphosphine, 

 in addition to the oxide. 



A simple method suggested itself for separating the two 

 bodies, depending upon their different solubility in water, the 

 oxide being soluble in all proportions, whilst the sulphide 

 readily crystallizes from a hot saturated solution. The distil- 

 late was accordingly dissolved in hot water, and as the solu- 

 tion cooled, beautiful needle-shaped crystals of considerable 

 length separated. They were collected on a filter, washed 

 with cold water, and recrystallized from boiling water. 



* Letts and Collie, loc. cit. 



