295 



favourable circumstances, can be fixed by the chlorinated derivatives 

 of marsh-gas, is determined by the number of chlorine-equivalents 

 which these substances contain. These bodies need not, however, 

 assimilate the maximum quantities of triethylphosphine represented 

 by these numbers. Thus dichloride of methylene is capable of fixing 

 either one or two molecules of phosphorus-base, the formation of the 

 ephemeral diatomic base being invariably preceded by that of the 

 more stable chloromethylated monophosphonium-compound. Similar 

 phenomena are observed in the action of chloroform and tetrachloride 

 of carbon. The compounds which I have described as resulting from 

 these reactions, are not the only products ; by changing the relative 

 proportions of the agents, a number of chlorinated phosphonium-bases 

 are formed so much resembling each other, that I have failed in 

 separating them. Nevertheless, by determining the amount of chlo- 

 rine and platinum in the mixed platinum-salts obtained from these 

 mixtures, I had no difficulty in recognizing the principle involved in 

 their formation. These substances stand to the final products of the 

 reaction of the triphosphonium and tetraphosphonium-series in rela- 

 tions similar to those which obtain between the chloromethylated 

 monophosphonium and the ephemeral diphosphom'um-compound. 



The results of these inquiries may be condensed in a few formulae. 



The chlorinated derivatives of marsh-gas exhibit, in their deport- 

 ment with the phosphorus-bases, the characters of hydrochloric acid. 

 The monochlorinated product has the saturating capacity of one 

 molecule of hydrochloric acid, the dichlorinated product of one or two 

 molecules, the tri chlorinated of 1, 2 or 3 molecules, the tetrachlori- 

 nated product, lastly, of 1, 2, 3 or 4 molecules: 



CH 3 Cl=(CH 3 y Cl. 



CH 2 C1 2 =(CH 2 C1)' C1=(CH 2 )" C1 2 . 



C H C1 3 = (C H C1 2 )' Cl= (C H Cl)" C1 2 = (C H)'" C1 3 . 



c ci 4 =(cci 3 y ci=(cci 2 )" ci 2 =(cciy"ci 3 =:c iv ci 4 . 



The action of chloride of methyl on triethylphosphine produces 

 only one salt ; that of dichloride of methylene produces two ; chloro- 

 form is capable of producing three ; and tetrachloride of carbon, four 



salts. 



Monochlorinated Marsh-gas. 

 Monatomic compound [(C H 3 ) (C 3 H.) 3 P] Cl. 



