MISCELLANEOUS METHODS AND APPARATUS. 71 



breakfast; the feces colored with the carmine or charcoal were then 

 considered a part of the feces belonging to the collection period. At 

 the end of the collection period, a marker was given with the following 

 breakfast and feces preceding the colored portion included in the feces 

 for this period. 



After the separation of the colored portion of the feces, the portions 

 to be analyzed were placed in glass jars in exactly the same manner as 

 the food samples were handled, 5 c.c. of concentrated hydrochloric 

 acid added to each jar and shipments made in special cases to guard 

 against breakage. 



Constipation. — As a result of the marked reduction in diet, constipa- 

 tion was of frequent occurrence, especially in the earlier stages of the 

 research. To offset this and profiting again by the extended experience 

 at Battle Creek Sanitarium, bran was administered in amounts desired 

 by the subjects. While practically all of the men were entirely unused 

 to bran, nearly all of the subjects asked for it and in rather large 

 amounts. Indeed, so much bran was taken that our attention was 

 called to the fact that this substance, instead of being mostly indi- 

 gestible fiber, contained a really large amount of available energy. 

 Consequently we found, much to our chagrin, that no small part of 

 the energy in the diet was supplied by the large amounts of bran 

 used which should therefore be taken into account. It thus became 

 necessary either to curtail the use of bran or to substitute it for other 

 food materials. 



In rare instances the subjects resorted to some simple physic, as salts 

 or oil. In no case was oil used during the periods when feces were 

 collected ; the energy of the feces was therefore not contaminated by the 

 energy of unabsorbed petroleum oil. Patent preparations containing 

 bran in various forms, such as biscuits, were liked by the subjects and 

 these, combined with an extensive use of bran, readily served to hold 

 constipation in check. Chef Hall also made some excellent bran 

 muffins which were greatly relished not only by the squad but by the 

 entire student body. The diet was further modified in the latter part 

 of the period by the use of somewhat bulky food materials, such as 

 spinach, which supplied coarse ballast. By these simple dietetic means 

 constipation was controlled. 



COLLECTION OF URINE. 



The importance of noting the nitrogen output during this period of 

 undernutrition led us to emphasize especially to the squad the necessity 

 for the complete collection of the urine for the entire period of the 

 research, or at least this was held up as an ideal. Each man was told 

 that the best and most perfect picture of the balance of income and outgo 

 of nitrogen could be obtained only by the faithful collection of all the 

 urine. The fact that we were able to secure practically every day 24- 



