602 
DE. A. W. HOFJklANN OX THE PHOSPHOEUS-BASES. 
possessing, however, a different crystalline form. I have fixed the composition of this 
substance by the determination of the bromine accessible to silver-salts. 
0*3980 grm. of bromide, precipitated by nitrate of silver, gave 0*2820 grm. of bromide 
of silver. 
The formula 
Cs H,3 P 81-3= [(C3 H, Br) (C Hj), P] Bi-, 
requires the following values — 
1 equiv. of Phosphonium 
1 equiv. of Bromine . 
1 equiv. of Bromide . 
Theory. 
t ^ 
184 69*70 
80 30*30 
^ 100*00 
Experiment. 
30*16 
This result was confirmed by several analyses of the corresponding 
Platinum-salt . — This is easily formed by treating the bromide -with chloride of silver, 
when a crystallizable chloride is produced, which yields with dichloride of platinum 
splendid orange-yellow needles, containing 
C5 Hi 3 P Br Pt CI3 = [(C2 H, Br) (C 11,), P], Pt Cl,. 
I. 0*5440 grm. of platinum-salt, treated with sulphuretted hydrogen, &c., gave 0*1390 
grm. of platinum. 
II. 0*495 grm. of platinum-salt, analysed in the same manner, gave 0*126 grm. of 
platinum. 
III. 0*304 grm. of platinum-salt gave 0*077 grm. of platinum. 
Tlieory. 
Experiment. 
I. 
11 . HI. 
1 equiv. of Phosphonium . 
. 184*0 
47*27 
1 equiv. of Platinum 
. 98*7 
25*36 25*55 
25*45 25 33 
3 equivs. of Chlorine 
. 106*5 
27*37 
1 equiv. of Platinum-salt . 
. 389*2 
100*00 
I have already mentioned that the bromide of broniethyl-trimethylphosphonium crystal- 
lizes differently from the bromide of the ethylated body. 'Whilst tlie latter is obtained 
in rhombic dodecahedrons, the methylated bromide affects forms belonging to the trime- 
tric system. Quintino Sella has made the following examination of this compound ; — 
Fig. 54:. 
“ System trimetric : — 
1 0 0, 1 1 0 = 60° 24'; 
0 01, 1 01 = 22° 9'. 
Forms observed; — 
1 0 0, 01 0, 0 01, 1 10, 21 1 (Fig. 54). 
