278 



PHILIP B. HAWK 



the fact that when the water of a diet is increased the urea is increased to 

 an extent beyond that which can he explained by the increase of fluid 

 increasing the facilities of mere excretion." 



The most direct evidence that an increased water ingestion increases 

 cellular activity was furnished by an experiment made in the writer's 

 laboratory (Howe, Mattill and Hawk (a), Wreath and Hawk). 



A dog was given 700 c.c. of water daily during a 59-day fast, at 

 which point the water ingestion was increased to 2,100 c.c. for each day 

 of a four-day interval. The increased water intake caused an increased 

 excretion of "total purin nitrogen," i.e., nitrogen in the form of purin 

 bases, uric acid, and allantoin. Inasmuch as this form of nitrogen has its 

 origin in the cell nucleus, we may consider that an increased output indi- 

 cates stimulated cellular activity and increased tissue disintegration. 



Certain other observations also indicate that water stimulates tissue 

 changes. For example in the case of the fasting dog just mentioned, the 

 increased water intake caused the appearance of considerable creatin in 

 the urine. There had been no creatin in this dog's urine for a considerable 

 interval before the high water intake. However, as soon as the water 

 ingestion of the animal was increased, creatin appeared in considerable 

 quantity in the urine. The creatin was interpreted as having arisen, at 

 least in part, from disintegrated muscular tissue. The data on this point 

 are embraced in the following table: 



TABLE II 

 PERCENTAGE EXCRETION IN TERMS OF TOTAL NITROGEN 



FASTING 700 C.C. WATER PER DAY 



FASTING 2100 C.C. WATER PER DAY 



Other observations made on men have been interpreted as indicating 

 that a high water ingestion causes a partial muscular disintegration result- 

 ing in the release of creatin, but not profound enough to yield the total 

 nitrogen content of the muscle. The output of creatin is, therefore, out 

 of all proportion to the increase in the excretion of total nitrogen (Fowler 

 and Hawk). 



That the chloride content of the urine is increased as a result of an 



