16 J. M. Crafts on Ethers of Arsenic Acid. 
obtained asia less nearly to the theoretical quantity ; 
there is, howev o difficulty in ny pure arsenious 
arsenious ether can be bere by washing the silver salt 
with common ether and finally by distilling the solution in 
ether. 
The action of alcoholate of sodium upon the chlorid, or, 
better still, upon the bromid of arsenic, furnishes the "best 
method for obtaining the arsenite of et L 
It is well known that the chlorid of arsenic combines with 
alcohol with evolution of heat to form a definite compound,* 
which distils without decomposition. 
When the bromid of arsenic is mixed with an equal volume 
of a the heat evolved is very slight (an elevation of tem- 
ure of 8° was noticed), and no definite combination appears 
to Ge formed. If alcoholate of sodium is added to a mixture 
of either the chlorid or bromid of arsenic with alcohol, a pre- 
cipitation of chlorid or bromid of sodium takes place imme- 
diately, and arsenite of ethyl is formed, but if the addition of 
the alcoholate is continued until all the chlorine or bromine is 
combined with sodium, the arsenite of ethyl is destroyed at 
the same time.t If the operation is terminated before all the 
chlorid or bromid of arsenic has been acted upon, a mixture of 
the undecomposed chlorid or bromid with arsenite of ethyl is is 
obtain 
It was ‘thought at first that the difference between the boiling 
int of the bromid of arsenic (222°) and that of the arsenite 
of arsenious acid will be noticed below. 
"he 
Se ot Miaiite of tide siete in dissolving 5 parts of 
romid of arsenic in absolute alcohol and in adding to the solu- 
es, Ann. Chem. und Pharm., exvi, p. 368. 
; feo be Comptes ion April, 1867. 
