DE. A. W. HOFMANN ON THE PHOSPHOEUS-BASES. 
521 
The nature of this transformation is clearly exhibited when a solution of the hydrate of 
the phospharsonium, filtered off in the cold from the excess of oxide of silver, is sub- 
mitted to ebulhtion. Immediately the clear liquid is rendered turbid from separated 
triethylarsine which becomes perceptible, moreover, by its powerful odour; the solu- 
tion now contains the hydrate of oxethylated triethylphosphonium. 
[(C, (C, p ^ JJ ,)3 As + KCs H 3 O) (C, H 3)3 P]|„ 
When the dibromide is boiled with the oxide of silver, a beautiful silver mirror is 
formed on the sides of the vessel, obviously in consequence of a partial oxidation of the 
liberated triethylarsine. 
Some experiments were made to produce a diatomic compound containing phosphorus 
and antimony. I expected to form this body, the dibromide of a phosphostibonium, by 
the action of triethylstibine on the bromethylated bromide, so frequently mentioned in 
this paper. The two bodies react upon one another, but only after protracted digestion 
or exposure to a rather high temperature. The product of the reaction is complex, 
yielding a comparatively small quantity of a difficultly soluble platinum-salt of diatomic 
appearance. I have repeatedly modified the reaction, and analysed the products in the 
form of platinum-salts : I omit to quote the detail of these experiments, since they have 
failed to disentangle the difficulties of the reaction. 
Some experiments upon the deportment of dibromide of ethylene with triethylarsine 
were more successful. The reaction between these two bodies had been selected as a 
subject of inquiry by Mr. W. Valentin, to whom I am indebted for valuable assistance 
at the earlier stages of these researches. Circumstances have subsequently prevented 
Mr. Valentin from canying out his plan, and I have therefore to take upon myself the 
responsibility for the following statements. The results obtained in the examination of 
the arsenic-compounds are by no means absolutely connected with the study of the 
phosphorus-bases, nevertheless I may be permitted to lay them before the Society, 
together with the account of the corresponding reaction in the phosphorus-series. 
MONAESONIEM-COMPOUNDS. 
Action of Dibeomide op Ethylene upon Teiethtlaesine. 
The experience gathered during the examination of the phosphorus-bodies enabled 
me to establish the nature of this reaction by a comparatively small number of platinum- 
determinations. 
Bromide of Bromethyl-triethylarsonium . — To avoid, as far as possible, the formation of 
the second product, a mixture of triethylarsine with a very large excess of dibromide of 
ethylene was digested in sealed tubes, at a temperature not exceeding 50° C. Notwith- 
standing this low temperature, the tubes invariably contained compressed gases. The 
MDCCCLX. 3 z 
