48 
Proceedings of the Royal Society 
225° C. (uncor.). Its composition was verified by determinations of 
carbon, hydrogen, and chlorine. 
Chloroplatinate oftetra-benzyl-phosphoMum , 2(C 7 H 4 ) 4 PCl,PtCl 4 . — 
Mixed with chloride of platinum the preceding body yields in alco- 
holic solution insoluble leaflets of a light orange colour, in aqueous 
solution a light yellow precipitate of the chloroplatinate of tetra- 
benzyl-phosphonium. 
Its formula was verified by determination of its carbon and 
hydrogen. 
The chloroplatinate is very slightly soluble in water and alcohol. 
Acid sulphate of tetra-benzyl-phosphonium , (C 7 H 4 ) 4 PIIS0 4 . — Up 
to the present time the normal sulphate has not been obtained. The 
acid sulphate is formed either by treating a solution of the chloride 
with sulphate of silver, or warming the dry chloride with strong 
sulphuric acid. It is more soluble than the chloride, and separates 
in plates from a hot and somewhat concentrated aqueous solution. 
Its analysis (carbon, hydrogen, and sulphuric acid) showed 
that it has the composition 
(C 7 H 7 ) 4 PHS0 4 
It is remarkable that the acid sulphate is obtained from the 
chloride and sulphate of silver instead of the normal sulphate. 
Action of Caustic Baryta on Acid Sulphate of Tetra-Benzyl-Phos- 
phonium. — The action which occurs when solutions of these two 
bodies are mixed, varies in a remarkable manner with the condi- 
tions of the experiment. 
In our earliest attempt to prepare the hydrate of tetra-benzyl- 
posphonium by this reaction, we failed to obtain any body easily 
soluble in water as we expected the hydrate would be. On repeat- 
ing the experiment we however obtained an easily soluble body 
which turned out to be the hydrate, but on attempting to prepare 
more of it we were again unsuccessful. 
We found, however, that although no body soluble in water was 
formed, boiling alcohol took up from the precipitated sulphate of 
barium a considerable quantity of a substance which was deposited 
in crystals as the solution cooled. 
Later experiments have shown us that the hydrate is only formed 
