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into contact with triethylphosphine, are instantaneously decomposed, 

 their sulphur being appropriated in the formation of the beautiful 



bisulphide 



E,PS 2 , 



which, as has been pointed out on a former occasion, is generated by 

 the action of free sulphur. As an illustration, the deportment of 

 bisulphide of nitrogen may be quoted. This substance, obtained by 

 the action of ammonia on chloride of sulphur, and as yet scarcely 

 touched upon as an agent of research, is instantaneously decomposed 

 into its constituents when acted upon by triethylphosphine, 

 E 3 P + NS 2 = E 3 PS 2 +N. 



Triethyl- Bisul- Bisulphide 



phosphine. phide of of triethyl- 



nitrogen. phosphine. 



The reaction is so violent that care must be taken to prevent the 

 phosphorus-base from being inflamed. 



Triethylphosphine is not less powerfully attacked by bisulphide of 

 carbon ; but the result is different. On mixing the two bodies in 

 the anhydrous condition, they are found to combine with explosive 

 violence, a deep crimson-coloured crystalline compound being pro- 

 duced. This substance is obtained in better crystals if ethereal 

 solutions, instead of the anhydrous compounds, be employed. The 

 new body separates in beautiful crimson leaflets the moment the two 

 solutions are mixed. This phenomenon is so characteristic, that 

 ever since it was first noticed, it has served me as a valuable test for 

 the detection of even minute traces of triethylphosphine. A watch- 

 glass, moistened with the liquid in which the phosphorus-base is sus- 

 pected, is held over a vessel containing bisulphide of carbon : the 

 vapour of this compound immediately causes the formation of a crimson 

 network of crystals, if the smallest quantity of triethylphosphine be 

 present. It is necessary that the base should be free ; its saline 

 solutions are not affected by bisulphide of carbon ; the reaction, 

 however, immediately appears when the base is liberated by the 

 addition of an alkali. 



The new body produced by the action of bisulphide of carbon 

 upon triethylphosphine is insoluble in water, nearly insoluble in 

 ether, but soluble in alcohol. From boiling alcohol it is deposited 

 on cooling in crimson needles, somewhat similar to the crystals of 



