653 



C U H 17 PC1, PtCl 2 . 



The gold-salt is a bright yellow crystalline precipitate, difficultly 

 soluble in boiling water, and not recrystallizable without some altera- 

 tion. The gold-determination agreed with the formula 



C 14 H 17 PC1, AuCl 3 . 



The preceding formulae are simple translations of the analytical 

 results, but they convey no idea regarding the nature of the new body. 

 Legitimate interpretation of these expressions, and a due apprecia- 

 tion of the conditions in which the new compounds are formed, un- 

 avoidably lead us to the conclusion that the formulae must be doubled. 

 The molecule of the new iodide thus becomes 



corresponding to an original bromide, 



C 28 H 34 P 2 Br 2 



which is simply formed by the association of 2 equivalents of triethyl- 

 phosphine and 1 equivalent of dibromide of ethylene, 



20 12 H 15 P+C 4 H 4 Br 2 =C 28 H 34 P 2 Br 2 . 



The formulae of the platinum-salt and of the gold-salt of course 

 have likewise to be doubled : 



Platinum-salt C 28 H 34 P 2 C1 2 , 2PtCl 2 , 

 Gold-salt C 28 H 34 P 2 C1 2 , 2AuCl 3 ; 



the number of platinum- and gold-equivalents which respectively ex- 

 ist in these compounds being apparently determined by the number 

 of triethylphosphine-equivalents associated in the new salt. I have 

 vainly endeavoured to produce compounds containing only one equi- 

 valent of platinum and gold, but have succeeded in procuring a well- 

 defined silver- compound : 



C 28 H 31 P a Br a) AgBr, 



which is formed by treating the new bromide with a quantity of oxide 

 of silver insufficient for complete decomposition. This compound is 

 a double salt of equal equivalents of the proximate constituents. 



The deportment of triethylphosphine with dibromide of ethylene, 

 and more particularly the formation of the new bromide, is not with- 



