270 
OBSERVATIONS ON ETHERIFICATION. 
that substance, in a sealed tube, to 360° (182° C). Even chloride 
of zinc produced no more, at the same temperature, than a trace 
of ether, perceptible to the sense of smell. 
Expt. 6. — To illustrate the ordinary process of ether-making, a 
mixture was prepared, as usually directed, of 
100 parts of oil of vitriol, 
48 " of alcohol (0.841), 
18.5 " of water. 
This liquid was sealed up in a glass tube, and heated to 290° 
(143° C.) for one hour. It became of a dark greenish-brown co- 
lor, and opalescent, with a gummy looking matter in small 
quantity. No stratum of ether formed upon the surface of the 
fluid. 
The tube was opened, and the fluid divided into two equal por- 
tions. One of the portions was mixed with half its volume of 
water, and the other with half its volume of alcohol, and 
both sealed up in glass tubes and exposed again to 290° for one 
hour. 
It would be expected, on the ordinary view of water setting free 
ether from sulphovinic acid, that much ether would be liberated 
in the mixture above, to which water was added. The ether which 
separated, however, amounted only to a thin film, after the liquid 
had stood for several days. In the other liquid, on the contrary, 
to which alcohol was added, the formation of the ether was con- 
siderable, a column of that liquid appearing, which somewhat ex- 
ceeded half the original volume of the alcohol added. In fact, the 
sulphovinic acid w T as nearly incapable of itself of yielding ether, 
even when treated with water. But it was capable of etherizing 
alcohol added to it, in the second mixture, like bisulphate of soda 
or any other acid salt of sulphuric acid. 
The conclusions which I would venture to draw from these ex- 
periments are the following : — 
The most direct and normal process for preparing ether, appears 
to be, to expose a mixture of oil of vitriol, with from four to eight 
times its volume of alcohol of 83 per cent, to a temperature of 
320° (160°C.) for a short time. Owing- to the volatility of the 
alcohol, this must be done under pressure, as in the sealed glass 
tube. The sulphuric acid then appears to exert an action upon 
