292 ' THE HUMAN MECHANISM 



which they contain is apt to make matters worse in many 

 cases of dyspepsia; by taking them frequently between 

 meals the appetite for wholesome food is impaired, and 

 excessive indulgence in them under any circumstances is 

 needless and foolish. 



7. Alcoholic beverages. In the case of an alcoholic drink 

 we have to deal with something which, like tea and coffee 

 and cocoa and " temperance drinks," is used as a beverage, 

 and to that extent must be classed in the same group. 

 Alcoholic drinks are, however, taken as stimulants and so 

 resemble tea and coffee and cocoa, but they differ from all 

 of these in their action upon the body. Moreover, their 

 abuse gives rise not only to degraded moral and social 

 conditions, but is also attended with bad hygienic effects. 

 Everyone should be informed of their nature and of the 

 dangers attending their use. 



The common alcoholic beverages consist of (1) malt 

 liquors, including beer and ale; (2) wines, such as hock, 

 claret, Burgundy, sherry, and champagne ; (3) distilled 

 liquors, including brandy, whisky, rum, and gin ; and 

 (4) liqueurs and cordials. These groups are distinguished 

 from one another largely by the method of preparation and 

 by the amount of alcohol they contain. Malt liquors are 

 fermented liquors which contain from three to eight per cent 

 of alcohol; wines are also fermented liquors, but contain 

 from seven to twenty per cent of alcohol; distilled liquors, 

 on the other hand, are first fermented and then concen- 

 trated by distillation, and contain from thirty to sixty-five 

 per cent of alcohol. In all these the most important con- 

 stituent, so far as their physiological action upon the body 

 is concerned, is the chemical compound known as ethyl 

 alcohol (C 2 H 6 O or C 2 H 6 . OH). 



8. Fermentation. The ethyl alcohol in each of these bev- 

 erages is produced by the action of yeast on sugar, and 

 this action is known as alcoholic fermentation. Yeast is a 



