=Spirits= differ from the two last groups, to begin with, in the amount of alcohol they contain. Thus, English beers contain from 3 to 6 per cent., German beers from 2 to 5 per cent., wines from 8 to 20, and all kinds of spirits from 37 to 58 per cent. of alcohol. They differ in the absence of the bitter principle of beer and much of the salts and sugar and ether of wines. They are all prepared by the distillation of some previously fermented liquor. =Brandy= ought to be made by the distillation of wine; and then contains, besides alcohol and water, small quantities of acetic, œnanthic, butylic, and valerianic ethers. But much of the brandy sold is simply made from potato spirit, by the addition of acetic ether, burnt sugar, etc. The starch of potatoes is converted into dextrin and dextrose by dilute acids, and then fermentation allowed. By the use of patent stills, all bye-products can be separated, a fairly pure alcohol known as _silent spirit_ being produced. This is largely employed in manufacturing spirits and in fortifying wines. =Whiskey= is prepared from malted barley, or from a mixture of grains, to which a sufficiency of malt to convert their starch into sugar has been added. In _grain whiskey_ the distillation is effected by steam in a patent (Coffey’s) still, which separates most of the bye-products (fusel oil, etc.) from the spirit. In _malt whiskey_, distilled in the old-fashioned pot-still, these bye-products are not separated. The improvement of whiskey effected by keeping is not due (Bell) to the diminution of fusel oil. Such a diminution does not occur. The percentage of alcohol diminishes by keeping, 6 to 8 per cent. proof spirit being lost by five years’ storage in wood. “Fusel oil” is a mixture of alcohols of higher boiling point than ethylic alcohol (amylic, propylic, etc.). Even in a bad whiskey not more than 1∕10 per cent. of fusel oil is present (about one grain in a glassful). Experimentally no marked effects have been produced by fusel oil, when it is less than 1 per cent. Possibly the presence of furfurol, of which there is a trace in malt whiskey, which disappears on keeping, may partially explain the disagreeable flavour of new whiskey. But it is fairly clear that those who argue that it is _bad_ whiskey and not _good_ whiskey which does harm are speaking without knowledge. It is not the quality but the quantity of whiskey which is responsible for so much moral and physical evil. =Gin= and =Hollands= are obtained from barley, and flavoured with juniper berries and other materials. The oil of juniper stimulates the urinary excretion. =Rum= is obtained by the distillation of molasses, and is usually kept for a long time in oak barrels. It is said thus to acquire more astringent matters than other spirits contain.