482 
DE. A. W. HOFMAXNT OX THE PHOSPHOEUS-BASES. 
forms an angle of about 30° with a line normal on face 0 01. In fact, a plate parallel 
to 0 1 0 stops the passage of a ray of polarized light in that dii-ection. Moreover, rings 
are observed through the faces 0 01, and in a plane parallel to the line of symmetry 
010, and rather inclined towards a line normal on such face. The angle of the optical 
axes, seen in this manner through the faces 0 01, appears to be very nearly 110°. 
The crystals have a very fine orange-colour and a ’vitreous lustre.” 
This platinum-salt was the first diphosphonium-compound -with yhich I became 
acquainted, a circumstance explaining the considerable number of analyses which were 
made of this salt. 
I. 0'6534 grm. of platinum-salt gave 0'5938 grm. of carbonic acid and 0’2995 grm. of 
water. 
II. 0‘7179 grm. of platinum-salt gave 0’6545 grm. of carbonic acid and 0'3135 grm. 
of water. 
III. 0'3568 grm. of platinum-salt gave 0'3289 grm. of carbonic acid and 0T5S5 grm. 
of water. 
IV. 0'3250 grm. of platinum-salt gave 0‘3009 grm. of carbonic acid and 0T480 grm. 
of water. 
V. 0'5809 grm. of platinum-salt gave 0'5228 grm. of carbonic acid and 0'2670 grm. 
of water. This compound had been prepared from a diphosphonium-salt obtained by 
the action of brominated bromide of ethyl upon triethylphosphine. 
VI. 0'7200 grm. of platinum-salt, when fused -with carbonate of sodium, gave 0-2120 
grm. of platinum and 0-9120 grm. of chloride of silver. 
VII. 0-4075 grm. of platinum-salt gave 0-1205 grm. of platinum and 0-5235 grm. of 
chloride of silver. 
VIII. 0-3470 grm. of platinum-salt gave 0-1030 grm. of platinum and 0-4428 grm. of 
chloride of silver. 
IX. 0-4615 grm. of platinum-salt gave 0-1355 grm. of platinum. 
X. 0-4105 grm. of platinum-salt gave 0-1210 grm. of platinum. This salt had been 
obtained by the action of chlorinated chloride of ethyl upon triethylphosphine. The 
mother-liquor furnished by the analysis of the iodide (V.) had served for its prepara- 
tion. 
XI. 0-6158 grm. of platinum-salt gave 0-7778 grm. of chloride of silver. 
These numbers fix the formula 
Cj4H34P2Pt.,CL = 
2PtCl„ 
the theoretical values of which I place in juxtaposition with the experimental per- 
centages : 
