DE. A. W. HOFMAXN ON THE PHOSPHOEUS-BASES. 
489 
II. 0'4675grm. of platinum-salt gave 0‘4573grm. of carbonic acid and 0'2352grin. 
of water. 
III. 0-3250 grm. of platinum-salt of the same preparation, treated with sulphuretted 
hydrogen, &c., gave 0-0890 grm. of platinum. 
Carbon 
Hydrogen 
Platinum . 
Theory. 
A 
Tetrethylphos- 
phouium-salt. 
. 27-26 
. 5-68 
. 28-02 
Oxethyl-triethyl- 
phosphoniuin-salt. 
26-07 
5-43 
26-81 
Experiment. 
I. II. III. 
26-34 26-67 
6-64 5-59 
27-38 
The experimental numbers characterize a mechanical mixture of the two platinum-salts. 
The action of heat upon the hydrate of the diphosphonium induces yet another trans- 
formation, to which I have already alluded when mentioning the dingy yellow insoluble 
precipitate which is formed on addition of dichloride of platinum to the product of the 
action of heat upon the hydrate, neutralized with hydrochloric acid. 
The following paragraph contains the* fragmentary information which I have collected 
in studying these changes. 
PAEADIPHOSPHONIHM-COMPOUNDS. 
The basic compound which yields the amorphous yellow platinum-salt repeatedly 
mentioned, is a transient product of the action of heat on the hydrated diphosphonium. 
If during distillation, the alkaline residue in the retort be tested from time to time with 
dichloride of platinum, a point is soon reached, when instead of the slightly crystal- 
line precipitate, perfectly insoluble in dilute hydrochloric acid, which appears at the 
commencement of the operation, an amorphous, generally dingy yellow precipitate is 
obtained, immediately dissohing on addition of a few drops of dilute hydrochloric acid. 
If the distillation be now inten’upted and the residue neutralized with hydrochloric 
acid, and mixed with a few drops of dichloride of platinum, a discoloured precipitate is 
thrown down, the filtrate from which, on addition of a further quantity of platinum- 
solution, yields the amoi-phous salt, of a light yellow colour, and in a state of purity. 
This salt exhibits no trace of crystalline structure, even when examined under the most 
powerful microscope : in the perfectly di-y state it is remarkably electrical, flying about 
in all directions during trituration. 
The same substance is obtained when the hydrated oxethyl-triethylphosphonium is 
submitted to the action of heat. By interrupting the process at a convenient time, and 
adding dichloride of platinum to the neutralized residue, phenomena identical with 
those just mentioned are observed. 
The compound which produces the amorphous yellow precipitate was lastly obtained, 
under the following cu’cumstances. 
While engaged with the study of the vinyl-compounds, the examination of which I 
MDCCCLX. 3 T 
