94 



WATER AND OTHER BEVERAGES 



varies in amount from two to seventy per cent of the 

 total bulk of the solution. 



Oxidation of alcohol. In its concentrated form, al- 

 cohol is a valuable fuel for cooking and heating pur- 

 poses, because of the large amount of carbon and hydro- 

 gen contained in it. In dilute form, a certain amount 

 of it is oxidized in the animal body and gives rise to 

 carbon dioxide and water. Scientists have long disputed 

 as to whether this combustion is similar to that which 

 food undergoes in the body and whether, as is the case 

 with food, it produces available energy. The essential 



test has been whether it would 

 replace an equivalent amount 

 of starch and sugar in a diet. 

 At first, it was thought that 

 this was not possible, but re- 

 cent experiments seem to indi- 

 cate that, when taken in mod- 

 erate quantities, it does act as 

 a food. This would seem to be 

 especially true in certain ill- 

 nesses where other foods can- 

 not be properly digested and 

 assimilated. In such cases, di- 

 lute alcohol appears to have the advantage of not re- 

 quiring previous digestion before it is absorbed and 

 utilized. 



Dangers of alcohol. Although alcohol may occa- 

 sionally have a certain value as f ood, this is the only thing 

 which can be said in its favor. Its other effects upon 

 animal organisms make it a very undesirable food, ex- 

 cept in cases of extreme illness. It acts upon the nerv- 

 ous system in such a harmful way, even when taken in 

 comparatively small doses, that it must be considered 



FIG. 58. Yeast: a, full-grown 

 plant, with a branch (bud) 

 partially developed ; b, c, 

 colonies formed by budding, 

 the individuals still attached. 

 (Magnified 750 diam.). 



