30 Influence of Inanition on Metabolism. 



solids found by the method explained above. Thus 1540.80 (the amount of 

 urine for the first day) 46.3 = 1494.50, the water for the first day. Corre- 

 sponding amounts for the other two days of the experiment were 927.00 grams 

 and 871.20 grams. 



Elimination of Water- Vapoe. 



The amounts of water-vapor in the ventilating air-current are of value to 

 show the loss of water from the body through the lungs and skin, to interpret 

 the hygrometric conditions, and to aid in computing the heat production. 



The data regarding the water in the ventilating air-current are given in 

 detail in table 5. Column a of the table shows the relative humidity of the 

 air inside the chamber. These data are important, since it is conceivable that 

 there may be noticeable difference? in the gaseous exchange and heat radiation 

 as the result of differences in hygrometric conditions. The method of obtaining 

 the figures is as follows : Knowing the total volume of air in the chamber to be 

 approximately 4900 liters and the temperature about 20 C. and that 1000 

 liters of air when saturated at 20 contain 17.11S grams of water, it is possible 

 to compute the amount of water-vapor which would be present in the air of 

 the chamber if it were completely saturated at 20. This amount would be 

 83.88 grams. From the ratio between this saturation amount and the actual 

 amount of water found, the relative humidity is readily obtained. In pre- 

 senting the results of subsequent experiments in this report the relative 

 humidity will not be given, but the weight of water-vapor in grams at the end 

 of each period, as shown in column b of table 5, will be included in the tables. 

 By following the method outlined above, the relative humidity can by simple 

 computation be readily obtained. In column c is recorded the gain or loss of 

 water-vapor by the air in the chamber from period to period. 



At the end of each experimental period, the determination of the amount of 

 moisture in the air is made by weighing the water absorbed from a known 

 amount of air in its passage through a U-tube containing pumice stone drenched 

 with sulphuric acid. The total amounts of water-vapor remaining in the 

 chamber as computed from this determination are recorded in column b. The 

 total water of respiration and perspiration, i. e., the amounts retained in the 

 sulphuric acid absorber and recorded in column d corrected for the variations 

 in the amount of water-vapor inside the chamber, are recorded in the last 

 column. In subsequent experiments, only the figures recorded in column b 

 and column e in this table will be presented. In certain experiments other 

 corrections are necessary for the amount of water condensed by the heat- 

 absorbing system and for the differences in weight of the underclothing, chair, 

 bed, bedding, etc. In the experiment here reported, however, no perceptible 

 moisture was observed on the absorbers in the chamber, and the data for 

 fluctuations in the weight of the bed, bedding, and clothing were not obtained. 



