Alcohol
An extremely useful solvent. There are a number of liquids referred to under this heading. Of these, undoubtedly the most important is ethyl alcohol, which is present, more or less, as the principal constituent of beers, wines, and spirits. Methyl alcohol is wood spirit which is poisonous, and "methylated spirit" contains wood spirit, together with such things as fusel oil, paraffin oil, and a violet aniline dye, most of which are added hopefully in an attempt to prevent its use for human consumption. Methylated spirit it not recommended for any of the purposes mendoned in this book unless it is specifically referred to, as its composition is far too uncertain. Isopropyl alcohol is an inexpensive substitute which can be used for most purposes except that of making potable liquor. Ethyl alcohol, when completely free from water and all impurities, is known as absolute alcohol. Fusel oil is not greatly poisonous in small quantities. It is a by-product of the manufacture of ethyl alcohol which is often present in home-made liquors of the more potent variety. Ethyl alcohol is subjected to a heavy Excise duty which is remitted in some cases when the substance is used for bona-fide manufacturing and scientific purposes.
Alcohol has great solvent powers and is much used in the preparation of lacquers and varnishes. It dissolves many fats and oils. Due to the fact that alcohol takes up water freely, fragile articles which have been wetted may be dried quickly by rinsing in alcohol, which removes the water and itself evaporates.
Alcohol is a powerful solvent for paints and varnishes. It will destroy dried oil films, and, for this reason, although it is much employed in picture-cleaning it needs to be handled with great care.
See Solvents.