456 
DE. A. W. HOIAIAXX OX THE PHOSPHOEL'S-BASES. 
Pig. 28. 
Pig. 29. 
Pig. 30. 
Lustre fatty. 
Hardness inferior to that of gypsum. 
The crystals have no action on polarized light.” 
By treating the bromide with silver-salts in the cold, the bromine external to the 
phosphonium-metal is replaced by the acid-radical imited ■s^ith the silver, while the 
bromine belonging to the phosphonium remains untouched. In this manner we obtain 
the salts of the new metal, which exhibit an inclination to unite with excess of the 
silver-salt, in the form of double compounds. The chloride and the nitrate prepared 
from the bromide by the action of chloride and nitrate of silver ai'e extremely soluble in 
water and alcohol, and crystallize indistinctly. The sulphate forms long white crystal- 
line needles, likewise very soluble in water and alcohol. It is very easily obtained by 
the action of sulphuretted hydrogen on the double salt which is formed by treating the 
bromide with sulphate of silver ; on adding alcohol and ether to the concentrated hquid 
containing free sulphuric acid, it is precipitated in crystals. The sulphate, treated with 
iodide of barium, yields the iodide, a salt which dissolves sparingly in water, and crystal- 
lizes in scales of a pearly lustre. 
I have not examined these salts more particularly, as they scarcely present any theo- 
retical interest, and as the composition of the bromide, which forms the starting-point 
of the series, is sufficiently corroborated by the analysis of the platinum- and gold-salts. 
Platinum-salt .- — The chloride obtained by digesting the bromide with excess of chlo- 
ride of silver is mixed with dichloride of platinum, when the platinum-salt is deposited 
on cooling in light orange-yellow prisms, frequently an inch in length. This salt is 
somewhat sparingly soluble in cold, more readily in boiling water, and may be crystal- 
lized without decomposition. During the recrystallizations, this salt, under circumstances 
not yet clearly made out, is occasionally obtained in crystals of an octohedral habitus. 
This platinum-salt, though somewhat sparingly soluble, is nevertheless essentially 
different from the platinum-salt of the diphosphoniuni to be described hereafter, which 
accompanies the bromethyl-triethylphosphonium. The latter is nearly insoluble in 
water, and is precipitated from the most dilute solutions. This character forms a means 
of testing the purity of the monophosphoniuni-broniide in the succession of crystalliza- 
tions to which it has to be submitted for the sake of purification. The salt is pure 
when the dilute solution, after being treated Avith chloride of silver, no longer gives a 
precipitate with dichloride of platinum. 
