BORIC ACID UPON NUTRITION. 15 



Fore Period. Borax Period. After Period. 



Nitrogen of Food . . . 88.326 90.118 89.884 



Nitrogen of Urine . . . 87.185 1 88.127 1^ 86.377,^ 



Nitrogen of Faeces . . . 2.122 ) 3.91 ) 3.624 J 



Nitrogen Balance . . -0.981 -1.928 -0.117 



Ratio of Urine Nitrogen 



to Food Nitrogen . . 98.6 per cent. 97.7 per cent. 96.0 per cent. 



It is thus evident that in this experiment, in spite of the 

 large doses of borax and the length of the period, proteid 

 metabolism is not modified in any noticeable degree. The 

 amount of nitrogen eliminated through the urine hi propor- 

 tion to the nitrogen of the food, during the borax period, 

 differs from that of the fore period only to a slight extent, 

 and this difference is due apparently to a diminished assimi- 

 lation of the proteid food. The change in the nitrogen 

 balance of the borax period is plainly caused by a slight 

 increase in the amount of fsecal nitrogen, and not to in- 

 creased metabolism, thus indicating, that the borax has a 

 tendency to diminish somewhat the absorption of proteid 

 food, or possibly leads to an increased secretion of mucus. 

 When, however, the nitrogen of the faeces of the borax period 

 is compared with both that of the fore and after periods the 

 increase is seen to be so slight that it is perhaps unwise to 

 attach much importance to it. Certainly the borax, though 

 given in doses sufficiently large to keep the animal on the 

 verge of nausea, did not in this experiment interfere greatly 

 with the digestion of any of the food-stuffs, since the faeces 

 of the borax period are not much greater in amount than 

 those of the after period, though somewhat larger than those 

 of the fore period. 



The weight of the animal during the twenty-seven days' 

 period showed a tendency to rise somewhat, i. e.^ from 10.9 

 kilos to 11.5 kilos. This, however, is not to be attributed to 

 a laying-on of fat nor to a retention of nitrogenous matter by 

 the body, but is the result simply of a diminished excretion of 

 water due to the presence of the borax. The results in this 

 connection are in direct opposition to those obtained by 



