144 LIFE AND DEATH. 



albuminoids, nitrogenous, quaternary, and ternary 

 substances. Proteid substances are capable of main- 

 taining life. Hence the preponderant importance 

 given by the eminent physiologist to this order of 

 foods. These results have since been verified. Pfluger, 

 of Bonn, gave a very convincing proof of this a few 

 years ago. He fed a dog, made it work, and finally 

 fattened it, by giving it nothing at all to eat but meat 

 from which had been extracted, as thoroughly as 

 possible, every other substance.^ The same experiment 

 showed that the organism can manufacture fats and 

 carbo-hydrates at the expense of the nitrogenous food, 

 when it does not find them ready formed in the ration. 

 The albumen will suffice for all the needs of energy and 

 and matter. To sum up, there is no necessary fat, no 

 carbohydrate is necessary; albuminoids alone are in- 

 dispensable. Theoretically, the animal and man alike 

 could maintain life by the exclusive use of proteid 

 food; but, practically, this is not possible for man, 

 because of the enormous amount of meat which 

 would have to be used (3 kilogrammes a day). 



Ordinary alimentation comprises a mixture of 

 three orders of substances, and to this mixture 

 albumen brings the plastic element materially neces- 

 sary for the reparation of the organism ; it also is 

 the source of energy. The two other varieties only 

 bring energy. In this mixed regimen the quantity 

 of albumen must never descend below a certain 

 minimum. The efforts of physiologists of late years 

 have tended to fix with precision this minimum 

 ration of albuminoids — or as we may briefly put it, 



^ It is not certain, however, that all the precautions taken 

 have the desired result. You cannot entirely deprive meat of its 

 carbohydrates. 



