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Alcohol is termed "absolute" when it has been deprived of every trace of water, and when its composition is exactly expressed by its chemical formula. To obtain it in this state it must be subjected to a series of delicate operations in the laboratory, which it would be impossible to perform on an industrial scale. In commerce it is known only in a state of greater or less dilution.

Alcohol possesses the power of dissolving a large number of substances insoluble in water and acids, such as many inorganic salts, phosphorus, sulphur, iodine, resins, essential oils, fats, coloring matters, etc. It precipitates albumen, gelatine, starch, gum, and other substances from their solutions. These properties render it an invaluable agent in the hands of the chemist.

Alcohol is found in, and may be obtained from, all substances—vegetable or other—which contain sugar. As stated above, it does not exist in these in the natural state, but is the product of the decomposition by fermentation of the saccharine principle contained therein; this decomposition yields the spirit in a very dilute state, but it is readily separated from the water with which it is mixed by processes of distillation, which will subsequently be described. The amount of alcohol which may be obtained from the different unfermented substances which yield it varies considerably, depending entirely upon the quantity of sugar which they contain.

Alcohol is produced either from raw materials containing starch, as potatoes, corn, barley, etc., or raw materials containing sugar, as grapes, beets, sugar-cane, etc.

The following are some of the most important sources from which alcohol is obtained: Grapes, apricots, cherries, peaches; currents, gooseberries, raspberries, strawberries, figs, plums, bananas, and many tropical fruits, artichokes, potatoes, carrots, turnips, beet-root, sweet corn, rice and other grains. Sugar-cane refuse, sorgum, molasses, wood, paper, and by a new French process from acetylene. On a large scale alcohol is usually obtained from sugar beets, molasses or the starch contained in potatoes, corn and other grains. The starch is converted into maltose by mixing with an infusion of malt. The maltose is then fermented by yeast. Sulphuric acid may be used to convert even woody fibre,

TABLE III.—PRINCIPAL ALCOHOLS.

Chemical Name.

Source.

Formula.

Boiling point °F.

1 Methyl

Distillation of

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