7^ VITALITY AND EFFICIENCY WITH RESTRICTED DIET. 



hour quantities of urine for 12 to 25 men during a period of 3 to 4 

 months is indubitable evidence of the fidehty of the men in this rather 

 tedious and embarrassing part of their cooperation. It involved in 

 many instances carrying special containers or in an emergency purchas- 

 ing special bottles, but in spite of all these inconveniences the squad 

 were extraordinarily faithful in living up to the ideal of collecting the 

 entire amount of urine. 



Usually the experimental day was ended, so far as the collection of 

 urine was concerned, from 5 to 6 o'clock in the morning, when the men 

 appeared for weighing and for the measurement of the gaseous metab- 

 ohsm. The entire collection of urine was mixed in one 24-hour speci- 

 men, which was carefully measured and checked by a second observer. 

 A 130 c.c. sample was then bottled, carefully labelled with dates, times, 

 etc., and shipped in special shipping cases, with provisions to avoid 

 breakage and, when necessary, freezing. Notwithstanding our care, 

 one shipment was lost from freezing. After this happened, the original 

 cases containing the urine bottles were packed inside of a larger case 

 and the intermediate space filled with sawdust. 



PREPARATION OF SAMPLES OF FOOD AND FECES FOR ANALYSIS. 



The samples of foods and feces received from Springfield at the Nutri- 

 tion Laboratory in the quart glass jars were first carefully weighed and 

 checked, then transferred to previously weighed white enamel pans, and 

 dried to approximately constant weight. To accomplish the drying of 

 the large nimiber of food samples, which were somewhat larger than 

 the usual samples dried, also the large number of feces, required a 

 specially constructed oven. This oven, which is shown in detail in 

 figure 1, consists of an asbestos-walled cabinet with doors that open 

 in front and stout wire-gauze shelves. At the top, through an 8-inch 

 furnace pipe, air was thrown out by means of an electric fan placed in 

 the pipe. At the bottom of the chamber an 8-inch furnace pipe led 

 air from the room into the oven; the air was heated by means of a large 

 gas burner of rose pattern. By regulating the speed of the electric fan 

 and the flow of gas, the temperature could be kept at approximately 

 70° C. the entire time. Throughout the whole period of 4 months, 

 there was rarely diflftculty with the temperature control. As fast as the 

 foods were partially dried, they were stirred, a fresh surface was ex- 

 posed, and the samples were moved about in the oven so as to take 

 advantage of the greatest heat and the greatest volume of air. 



When the samples were thoroughly dried so as to be in condition for 

 grinding, they were allowed to reach room temperature and stand in 

 the room for 24 hours or more. They were then weighed, put through 

 a hand mill or meat chopper one or more times, and finally bottled 

 either in the regular glass jars or in smaller glass jars, with stoppers, 

 ready for analysis. At this stage the recorded weights of the dried 



