70 VITALITY AND EFFICIENCY WITH RESTRICTED DIET. 



local restaurant which provided a special table for the 12 men and served 

 a prescribed menu. Here again the portions for the thirteenth and 

 fourteenth men, respectively, were placed in pans and subsequently 

 analyzed. Since the diet used on the periodic visits to Boston at this 

 restaurant was substantially the same for every visit to Boston, the 

 control was admirable on the probable value of protein and energy in the 

 diet served the subjects at the restaurant. 



Each morning of these Boston experiments, a standard simple 

 breakfast was served in the Laboratory. The diet for this breakfast 

 also remained unaltered throughout the entire period of experimenting 

 and was frequently analyzed and its composition checked. The prep- 

 aration of the breakfast was left in the careful hands of Mr. Henry W. 

 Fudge of the Nutrition Laboratory staff. 



Occasionally it became necessary for the men, particularly late Sun- 

 day afternoon, to eat a light lunch away from the training table. This 

 lunch always included some standard material, frequently a standard 

 brand of cake chocolate and sweet cake or cookies; samples of these 

 were weighed, analyzed, and carefully controlled. 



COLLECTION AND SEPARATION OF FECES. 



Although, with normal young men having presumably normal diges- 

 tion, standard factors for digestibility of our conmion food materials 

 may be used to compute the probable fecal output of nitrogen and 

 energy per day, it seemed necessary, when there were to be material 

 reductions in the diet, not to assume that there would necessarily be 

 the same proportion of energy and nitrogen lost through the feces as 

 would commonly occur with people subsisting upon full diet. Conse- 

 quently arrangements were made to obtain representative samples of 

 feces from time to time. It was impracticable, owing to the long period 

 of the investigation, to collect the feces for the entire time. Such col- 

 lections were made at the beginning of the experiment and approxi- 

 mately every other week throughout its continuance. The length of 

 each period for the collection of feces ranged from 3 to 16 days. 



The feces were collected in numbered sheet-iron pans, one of which 

 was assigned to each member of the squad ; care was taken to avoid loss 

 of urine at the time of defecation. The pans were covered with tin 

 covers and the subjects carefully instructed, especially at the beginning 

 and end of the period of collection, to indicate the first portion of feces 

 passed. 



The separation of feces was made by administering a marker of some 

 kind. At first powdered charcoal or lamp black was used, but later, in 

 accordance with the extended experience at Battle Creek Sanitarium, 

 carmine was employed. Markers were put in gelatine capsules and 3 

 capsules were given simultaneously according to the following schedule: 

 On the day of the first collection of feces, the marker was given before 



