462 Royal Society :-— 
By treating its solution with hydriodie acid, or with hydrochloric 
acid and dichloride of platinum, it is at once perceived that the action 
of the oxide of silver has profoundly changed the original system of 
molecules. Hydriodic acid no longer produces the salt difficultly 
soluble in alcohol ; by evaporating the solution a crystalline residue 
is obtained, which easily separates into a viscous, extremely soluble 
substance, and splendid erystals of an iodide, very soluble in water 
and alcohol, but insoluble in ether. The analysis of this iodide has 
proved it to contain o, H, 
C,H, PIS] Gy’ ¢ P| 
UH 
This formula represents the iodide of methyl-triethylphosphonium, 
which was formerly obtained by M. Cahours and myself, by acting 
with iodide of methyle upon triethylphosphine. 
The alkaline liquid, obtained by the action of oxide of silver upon 
the tri-iodide, when saturated with hydrochloric acid, yields no longer 
the platinum salt, difficultly soluble in water but soluble in hydro- 
chloric acid. In a dilute solution no precipitate whatever takes 
place, and only after considerable evaporation well-defined deep 
orange-yellow octahedrons are deposited, which contain 
C, H, 
C,,H,, PCL, PtCl,= B H, 5 Cl, Pt Cl 
14 18 > a4 C, H, ? 2° 
C,H, 
From these results it is obvious that the triphosphonium-salt, 
when submitted to the action of oxide of silver, passes over into a 
monophosphonium-compound. The latter is not the sole product of 
the reaction; I have already alluded to the viscous deliquescent 
substance which accompanies the iodide of methyl-triethylphospho- 
nium. This is an iodide which, in the solution produced by the 
action of oxide of silver upon the original tri-iodide, exists in the form 
of oxide. The latter substance is easily recognized by evaporating 
the solution of oxide of methyl-triethylphosphonium, and adding a 
concentrated solution of potassa, when the oily globules characteristic 
of the dioxide of triethylphosphonium separate, which disappear 
immediately on addition of water. 
The metamorphosis of the tri-iodide, under the influence of oxide 
of silver, is represented by the following equation :— 
(C,H)! C,H, Ae 
(C,H). lp |1.43A¢0+3HO=3AeI+| Hs lp} boolean bPo 
(C, H,), ps fa . 6 C,H, at iad 3 
(C) BD; C,H, "alee 
H 
The tri-iodide which forms the subject of this Note is not the only 
product of the reaction between iodoform and triethylphosphine. 
There are other compounds formed, especially when the iodoform is 
employed in great excess. The nature of these bodies, which may 
be divined from the examination of the corresponding compounds in 
the diatomic series, is not yet fixed by experiment. 
