BORIC ACID UPON NUTRITION. 5 



assimilation of the food and perhaps, at the same time, gives 

 rise to an increased secretion of mucus with a possible increase 

 in the discharge of epithelial cells from the intestinal mucosa. 

 This latter, however, is purely conjectural. Increased secretion 

 of bile is also said to result from the action of boric acid. On 

 the pulse and temperature no action was observed. 



It is thus quite evident that the influence of borax and 

 boric acid on nutrition, and especially their influence on 

 proteid metabolism, is by no means wholly settled. The 

 preceding statements clearly emphasize the uncertainty of 

 our present information on the more essential features of the 

 question before us, and we have therefore deemed it desirable 

 to carry out, as thoroughly as possible, a series of experiments 

 upon the action of both borax and boric acid on proteid 

 metabolism and related phases of nutrition. 



Conduct of the Experiments. The experiments were con- 

 ducted wholly upon full-grown dogs ranging hi weight from 

 8 to 12 kilos. The animals were confined in suitable cages 

 partially lined with galvanized iron and with the floor so 

 arranged that both fluid and solid excreta could be collected 

 in their entirety, while the upper portions of the cage were so 

 constructed as to permit unrestricted circulation of air. In 

 view of the length of the experiments ranging from twenty- 

 seven to fifty-six days each, with periods of eight to ten days' 

 duration it seemed inadvisable as well as unnecessary to 

 empty the bladder each day with a catheter. Such diurnal 

 variations as might possibly occur from incomplete emptying 

 of the bladder at the end of the twenty-four hours would 

 obviously be neutralized in periods of the above length, and 

 consequently the urine was collected as naturally excreted, 

 thus avoiding any possible disturbance of the normal condition 

 of the bladder, etc. At the end of each twenty-four hours, the 

 urine collected was combined, and its volume, specific gravity, 

 etc., determined, after which the bottom of the cage was 

 rinsed with a little distilled water and these washings added 

 to the main fluid. The latter was then made up to some 

 convenient volume in preparation for the daily analysis. 



