DE. A. W. HOFMANN ON THE PHOSPHOEHS-BASES. 
475 
complete. A variety of monophosphonium- and monarsonium-salts, and lastly of com- 
pounds of phosphammoniums and phospharsoniums, submitted to the same process, have 
furnished perfectly similar results. Hydrochloric acid occasionally produces crystal- 
line precipitates in the concentrated solutions of the iodates, even of bases containing 
unreplaced hydrogen ; these precipitates disappear, however, on addition of water, or on 
gently warming, and are essentially different from the compounds previously mentioned. 
Sulphur dissolves in a concentrated solution of the dihydrate, although with difficulty, to 
a yellow liquid, which precipitates the black sulphide from lead-solutions, and is decom- 
posed hy acids, with separation of sulphur and evolution of sulphuretted hydrogen. 
Phosphorus is not attacked by the solution of the hydrate, not a trace of phosphoretted 
hydrogen being evolved even by protracted ebullition. 
Pisulphhydrate . — The solution of the base saturated with hydrosulphuric acid, when 
allowed to remain for some time over sulphuric acid in vacuo, dries up to a gummy 
mass, which exhibits as little inclination to crystallize as the dihydrate itself. When 
evaporated on the water-bath in contact with the air, the disulphhydrate is decomposed, 
the sulphur being oxidized ; ultimately an imperfect crystallization of the sulphate 
remains behind. 
LHchloride . — This salt is easily obtained by treating the dibromide or the di-iodide 
with chloride of silver, and also by saturating the free base with hydrochloric acid ; it 
is extremely soluble in water and in alcohol, insoluble in ether. The concentrated solu- 
tion solidifies over sulphuric acid into a mass of large and highly deliquescent crystalline 
plates of a pearly lustre, which may be exposed to a very high temperature (290° to 300°) 
without the slightest alteration. The salt is precipitated unchanged from its aqueous 
solution by potassa. For analysis, the salt was dried in vacuo over sulphuric acid. 
0-4325 grm. of dichloride gave 0-3670 grm. of chloride of silver. 
The chloride accordingly contains 
C,,ll,,F,Ck = 
L 
(C2H4) 
„(C2H5)3Pn 
(C2H3)3P 
CL 
Theory. 
1 equiv. of Diphosphonium . 264 78-81 
2 equivs. of Chlorine . . . 71 21-19 
1 equiv. of Dichloride . . . 335 100-00 
Experiment. 
20-99 
The dichloride forms with metallic chlorides numerous well-crystallized double com- 
pounds, some of which will be more particularly described hereafter. 
The dichloride of the ethylene-diphosphonium is likewise produced by the action of 
monochlorinated chloride of ethyl, prepared in accordance with Kegnault’s indications, 
by the action of chlorine upon chloride of ethyl. The chlorinated compound acts but 
slowly upon triethyl phosphine at 100° C. By digesting the mixture for twenty-four hours 
at 120°, a considerable proportion solidified to a white fibrous crystalline mass, which 
3 E 2 
