2 INFLUENCE OF BORAX AND 



conclusions which are so much at variance cannot be accepted 

 without careful consideration. 



Cyon's experiments were conducted simultaneously on three 

 full-grown dogs which were fed upon a diet almost exclusively 

 proteid. His observations were practically limited to deter- 

 mining changes in body-weight during short periods, with an 

 estimation of the nitrogen of the urine. He found that during 

 the period when borax was included in the food, the animals 

 gained noticeably in body-weight and that less nitrogen was 

 contained in the excreta than in the ingesta. From these 

 very crude observations the conclusion was drawn that borax, 

 even to the extent of 12 grams per day, may be ingested with 

 the food, especially when the latter is essentially proteid in 

 nature, without provoking the slightest disturbance in general 

 nutrition. Further, Cyon appeared to see in his results 

 evidence that borax, if substituted for common salt hi food, 

 will facilitate the assimilation of the latter and bring about a 

 great increase in the weight of the animal. Such deductions, 

 however, were wholly unwarranted from the data at hand, for 

 not only were the periods of observation exceedingly short, 

 but, as pointed out by both Gruber * and C. Voit,f the animals 

 at the beginning were much emaciated and received throughout 

 the experiment such excessive quantities of meat that increase 

 of body-weight would have inevitably followed without the 

 presence of borax. Consequently, all that can be inferred 

 legitimately from Cyon's experiments is that assimilation and 

 general metabolism were not seriously affected by borax in 

 the quantities given. 



In Gruber's work more scientific methods were pursued, 

 but it may well be questioned whether the conditions under 

 which the experiments were conducted were adapted for 

 bringing out clearly the full action of borax upon proteid 

 metabolism. The two dogs employed were fed simply upon 

 meat and water, and were presumably in a condition of 

 nitrogenous equilibrium. In the first experiment, where the 



* Gmber, loc. cit 



t Voit, Hermann's Handbuch der Physiologic, Band 6, Theil I, p. 165. 



