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EUGENE F. DU BOIS 



their caloric requirements. Kocher gave two normal men diets containing 

 5,089 calories and only 1.01 gm. nitrogen. On this diet the urinary 

 nitrogen fell to about 3 grams and rose in one case to 3. 77 gm. in the 

 other to 4.69 gm. after a walk of 60 kilometers. On the day of the walks 

 the protein must have furnished only about 2 per cent of the total calories. 

 The bed-ridden fever patients on similar diets never excreted less than 



Fig. 12. Nitrogen minimum experiment of R. A. Kocher on patient with para- 

 typhoid fever. The subject was given a liberal diet with low nitrogen content but 

 the nitrogen elimination did not approach the normal minimum until the tempera- 

 ture had fallen. 



10 grams of nitrogen in the urine until the temperature had fallen to 

 normal. The results on one of his patients with paratyphoid fever are 

 shown in Fig. 12. 



This experiment shows the importance of studying the nitrogen 

 minimum, the "wear and tear quota" of Rubner, which has been found to 

 lie between 2 and 4 grama for healthy men. When a subject is on a 

 diet which contains more than this amount of nitrogen the percentage of 

 calories furnished by protein is merely a matter of proportion between 

 caloric expenditure and consumption of protein either of the food or the 



