ETHER. In Chemistry, this term is applied to a highly volatile, fragrant, in flammable, and intoxicating liquid, pro duced by distilling a mixture of equal weights of sulphuric acid and alcohol. When these liquids mutually act on each other, a series of complicated changes ensue, which terminate in the conversion of alcohol into ether. Ether, like alco hol, may be regarded as a compound of hydrocarbon and water ; and if alcohol be considered as consisting of one equiva lent of olefiant hydrocarbon=14, and one of water=9, either may be regarded as constituted of two olefiant hydrocarbon (14X2)=28, and one of water=9 : hence, the equivalent of alcohol being 14+9=23, that of ether will be 14X2=28+9=37 ; and the process of etherification may be stated to consist in the abstraction from alcohol of one half of its elemental water. By some, ether is regarded as the oxide of a peculiar hydrocarbon, which they term ethule, composed of 4 equivalents of carbon and 5 equivalents of hydrogen ; and alcohol must in that case be consid ered as hydrate of ether.
Ether, or, as it is often called, to dis tinguish it from analogous products ob tained by the intervention of other acids, sulphuric ether, is a limpid colorless fluid, of an agreeable odour, and a hot pungent taste. Its specific gravity is about 0-713, though that of the shops is usually heavier ; it boils at about 98°, and freezes at the low temperature of 46° below 0°. The specific gravity of ethereal vapor compared with atmospheric air is as 258 to 100. Ether is sparingly soluble in wa ter, which takes up about a tenth of its bulk ; it dissolves in all proportions in alcohol. The principal use of ether is in medicine. When taken internally, it is stimulant ; and it is sometimes applied externally, by reason of the cold produced during its evaporation, as an ingredient in refrigerating lotions.
The most profitable way of manufac turing ether has been pointed out by Bonney. It consists in letting the alco hol drop in a slender stream into the acid, previously heated to the etherifying tem perature. If the acid in this case were concentrated to 1-846, the reaction would be too violent, and the ether wo.dd be transformed into bicarbureted hydrogen (dihydrate of carbon). It is therefore
necessary to dilute the acid down to the of 1.780 ; but this dilution may be preferably effected with alcohol, in stead of water, by mixing three parts of the strongest acid with two of alcohol, specific gravity 0.830, and distilling off a portion of the ether thereby generated ; after which the stream of alcohol is to be introduced into the tubulure of the re tort through a small glass tube plunged into the mixture ; this tube being the prolongation of a metallic syphon, whose shorter leg dips into a bottle filled with alcohol. The longer leg is furnished with a stop-cock, for regulating at plea sure the alcoholic streamlet. The dis tilled vapors should be transmitted through a worm of pure tin, surrounded by cold water, and the condensed fluid received in a glass bottle. The quantity of alcohol which can be thus converted into ether by a given weight of sulphuric acid, has not hitherto been accurately de termined; but it is at least double. In operating in this way, neither sulphurous acid nor sweet oil of wine is generated, while the residuary liquid in the retort continues limpid and of a merely brown ish yellow color. No sulphovinic acid is formed, and according to the experiments of Geiger, the proportion of ether ap proaches to what theory shows to be the maximum amount. In fact, 57 parts of alcohol of 0.83 sp. gray, being equivalent to 46.8 parts of anhydrous alcohol, yield, according to Geiger, 33i parts of ether ; and by calculation they should yield 37+. The ether of the first distillation is ne ver pure, but always contains a certain quantity of alcohol. The density of that product is usually 0.78, and if prepared by the first of the above methods, con tains, besides alcohol, pretty frequently sulphurous acid, and sweet oil of wine ; impurities from which it must be freed. Being agitated with its bulk of milk of lime, both the acid and the alcohol are removed at the same time ; and if it be then decanted and agitated, first with its bulk of water, next decanted into a re tort containing chloride of calcium in coarse powder, and distilled, one third of perfectly pure ether may be drawn over.