BORIC ACID UPON NUTRITION. 23 



experiment, but upon the excretion of total and combined 

 sulphuric acid, chlorine, and phosphoric acid, no tangible 

 effect is produced. Certainly, the results in connection with 

 combined sulphuric acid do not indicate any retarding effect 

 upon the putrefactive processes of the intestine. In this 

 connection it will be remembered that in Forster's experiments 

 on man doses of boric acid, corresponding to those used by us, 

 apparently gave rise to a marked retardation in the amount of 

 ethereal sulphate excreted. As a result, Forster arrived at 

 the conclusion that boric acid materially reduces intestinal 

 putrefaction. Our results, however, show no action of this 

 kind in the dog, and we are inclined to the view that both 

 borax and boric acid are too rapidly eliminated from the 

 system to be very effective in the intestine. As already 

 stated, the elimination of borax and boric acid through the 

 urine commences almost immediately after their ingestion, 

 and it is very questionable, therefore, whether, with moderate 

 doses of these substances, enough would remain unabsorbed 

 at the lower end of the small intestine to exert much influence 

 upon the growth and development of micro-organisms. Cer- 

 tainly, the faeces do not ordinarily contain any appreciable 

 amount of borax or boric acid after these substances have 

 been administered in moderate quantities, although obviously 

 the length of time the faeces are forming will have some 

 influence upon their content of soluble matter. In only one 

 instance, to be detailed later, where a very large dose of borax 

 was given, could any decided reaction for boric acid be 

 obtained in the faeces. Johnson* states that in the case of 

 the human organism borax and boric acid show great 

 irregularity in their appearance in the faeces, and that he was 

 able to detect them in the latter only in six cases out of 

 fourteen, although daily doses of 0.9-3.0 grams of boric acid 

 were given. 



Lastly, it is to be noted that in our experiment with boric 

 acid there is no such increase in the excretion of phosphoric 



* Johnson, Ueber die Ausscheidung von Borsaure und Borax aus dem 

 menschlichen Organismus. Jahresbericht f. Thierchemie, 1885, p. 235. 



