HYDROSULPIIURIC AND II YD ROSE LE NIC ETHERS. 319 
ART. LI.— HYDROSULPHURIC AND HYDROSELENIC 
ETHERS. By C. Lowig. 
Oxalic ether renders essential service in the preparation 
of several ethers of the hydracids, which have not hitherto 
been known, as for instance the hydrosulphuric and hydro- 
selenic, by bringing it in contact with the sulphuret and sele- 
niuret of potassium. Hydrocyanic and hydrosulfocyanic 
ethers are prepared in the same manner. Mutual decompo- 
sition at the same time takes place with difficulty, and even 
with a large excess of the compound of potassium, a very con- 
siderable quantity of undecomposed oxalic ether passes over 
by distillation. Hydrosulphuric ether is obtained in the fol- 
lowing manner; simple sulphuret of potassium, prepared by 
decomposing the sulphate of potassa with charcoal, &c. re- 
duced in a heated capsule to a fine powder, is introduced 
while warm into a retort, and then mixed with a sufficient 
quantity of oxalic ether, to form a thick pap. After the mix- 
ture has been allowed to remain during several hours exposed 
to a moderate heat, and great care has been taken to exclude 
the introduction of moisture, so that no sulphuretted hydro- 
gen, or alcohol may form, the process of distillation is com- 
menced and continued with increase of heat until the oxalate 
of potassa which has been formed commences to be decom- 
posed. The product of the distillation, composed of hydro- 
sulphuric and oxalic ethers, is agitated during the requisite 
length of time with the concentrated solution of pure potassa, 
or sulphuret of barium, which decomposes the oxalic ether. 
The hydrosulphuric ether thus purified, is decanted and rec- 
tified with the chloride of calcium. Its purity is tested by 
the circumstance, that agitated with the solution of sulphuret 
of barium it no longer affords a precipitate. 
Hydrosulphuric ether is lighter than water and possesses an 
extremely disagreeable odour, of ether and assafoetida, which is 
very diffusible. It has a sweet persistent taste, and has no 
