Prep. Ether is purified by well washing it with water, digesting it for twenty-four hours with recently burned lime and chloride of calcium, and then distilling it from this mixture with a gentle heat.

Prop. & Comp. Pure ether should have a specific gravity not exceeding 0.720. It does not coagulate the albumen of blood, and is a powerful solvent of a limited number of substances, such as fixed and volatile oils, resins, a few alkaloids, gun cotton, iodine, bromine, bichloride of mercury, etc.

Use. Pure ether is used in the preparation of some alkaloids, as aconitia, in the estimation of quinia in cinchona bark, and to test the purity of some medicinal substances.

Adulterations. Ether may contain alcohol, which increases its specific gravity, and causes it to coagulate the serum of the blood; water and sulphurous acid may also be present, adding to its weight, and giving it an acid reaction.