294 THE HUMAN MECHANISM 



conditions under which the fermentation takes place and 

 the character of the malt and the yeast employed. German 

 beers contain from three to four per cent of alcohol; ale 

 contains from four to six per cent. 



10. Wines. Wine is produced by the fermentation of the 

 juice obtained by crushing grapes, and the yeast comes from 

 the "bloom" on the skin of the grapes. The juice, or "must," 

 thus extracted is allowed to undergo fermentation, and the 

 fermented liquid is wine. Most wines, however, are sub- 

 jected to subsequent treatment. Some are allowed to ripen 

 in wooden casks, during which process there take place 

 chemical changes which give to each wine its peculiar flavor. 

 In other cases the wine is "fortified" by the direct addition 

 of alcohol. Wines differ from one another according to the 

 variety of the grape used in making the must, according to 

 the variety of yeast used for fermentation, and according to 

 other circumstances. 



11. Distilled liquors and spirits. This group of alcoholic 

 beverages contains the highest percentage of alcohol, and 

 includes whisky, brandy, rum, and gin. In the making of 

 all of these the essential procedure is the same ; namely, 

 first to produce fermentation in some sugary liquid and 

 afterwards to distill from the products of this fermentation 

 its alcohol and some other volatile constituents. Whisky is 

 made by distilling fermented corn or rye ; brandy may be 

 spoken of as distilled wine; rum is distilled from fermented 

 molasses, and gin from a fermented mixture of rye and 

 malt juniper berries and other substances being added to 

 the distilled product. In general, distilled liquors contain 

 from thirty to sixty per cent of alcohol. 



With these differences of preparation, alcoholic beverages 

 differ greatly among themselves, independently of the quan- 

 tity of alcohol they contain, and some of their special effects 

 are due to other constituents. The chief danger of most of 



