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ALCOHOLS

Ordinary Alcohol Ethyl Alcohol is only one of a series of homologous alcohols of ascending specific gravities and boilingpoints, the lower members being colourless mobile liquids, the middle ones of more oily character, and the higher ones solid, like paraffin in appearance and without taste or odour. Some are found in nature in combination with organic acids in essential oils and waxes. Methyl Alcohol, CII.,OH, is contained in combination with salicylic acid in oil of wintergreen, and is found among the products of the distillation of wood. It is a limpid, colourless, volatile liquid which boils at 66 degrees C., has a sp. gr. of 08, burns with a nonluminous flame, and is a solvent of fats and oils. It is soluble in water, and is used commercially in making spirit varnishes, polishes, and for “methyating” spirits of wine. Upon oxidation, it yields formaldehyde, and finally formic acid. Ethyl Alcohol is a limpid, colourless, volatile, inflammable liquid which boils at 783 degrees C., and has a sp. gr. of 0*79. By oxidation, it is converted into acetaldehyde, and finally acetic acid. It is the product of the fermentation of sugar, and the intoxicating pi inci] ile of wines, beers, and spirits. Alcohol is prepared commercially from the starches of cereals or potatoes or from sugar by processes of fermentation. The starches are first of all converted into maltose by the ac tion of malt, or otherwise saccharified, the extract or “wort” being then subjected to fermentation as in brewing, and subsequently distilled in order to obtain the alcohol thus produced. This process of fermentation has been applied to the waste sulphite liquors resulting from pulp production. In the Philippine Islands, alcohol is made on a commercial scale from the sap of the Nipa palm, although the production of sugar from that source is at present only in the experimental stage. Alcohol is also made to some extent from woodwaste and sawdust by conversion of their cellulose contents into saccharoids and subsequent fermentation. Pine wood sawdust is stated to give the best result, yielding not less than 12 per cent, calculated on the dry sawdust. The “Amylo” process carried on near Lille depends upon the use of certain moulds, such as the A spergiUacea, for saccharifying starch instead of maltthe Rhizopus dele mar or Mucor foulard being now almost exclusively employedthus avoiding the formation of the unfermentable dextrin# which result to some extent when malt is used. The yeast used for fermenting the material thus prepared exercises its optimum effect at 38 degrees C., and the process, which takes in all, four days to complete, yields up to 975 per cent, of the alcohol theoretically obtainable. Attempts have also been made to produce ethylic alcohol from the ethylene contained in cokeoven gases by absorbing it in 95 per cent, sulphuric acid and hydrolizing the ethyl sulphate thus produced by dilution of the acid mixture with water or steaming, thus producing alcohol, which is recovered by distillation and regenerating the sulphuric acid. Of course the gas, prior to this procedure, is freed from tar, ammonia, naphthalene, benzol, sulphuretted hydrogen, the higher olennes, and water vapour in the order as here given. It is on record that rf> gallons of alcohol can be thus obtained from each ton of the particular Durham coal employed. Alcohol is soluble in water, and is largely used as a solvent, in the manufacture of explosives, chemicals, perfumes, lacquers, pharmaceutical extracts and tinctures; also as a fuel, in the compounding of drinks, and for preserving anatomical specimens. Although its calorific value is not much more than one half that of petrol, its efficiency is much greater owing to its relatively greater combustion. It can be compressed to a greater extent, and this property of highignition temperature under compression is not materially altered by admixture with 20 per cent, benzene or petrol. Such a mixture readily starts in the cold and runs smoothly; so that i+

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