42 Influence of Inanition on Metabolism. 



difference between the loss represented in table 10 and the intake of water as 

 given in table 2; consequently, on the first day, the loss of water from body 

 tissues would be 2247.48 1342.50, or 904.98 grams. A similar computation 

 shows the losses of the second and third days to be 295.67 and 404.35 grams, 

 respectively. The data for obtaining these losses are tabulated in table 11. 



Aside from the preformed water in' the muscles and tissues of the body which 

 was lost during fasting, there remains to be considered the water resulting from 

 the oxidation of the protein, fats, and carbohydrates katabolized, or the water 

 of oxidation of the organic hydrogen contained in these compounds. Since this 

 water was measured together with the rest of the output, it is included in the 

 total amount of water eliminated from the body, namely, column c. Deducting 

 the preformed water lost (column d), the values for the water of oxidation of 

 the organic hydrogen are obtained. These are recorded in column g. 



Output of Heat. 



Measurements with the respiration calorimeter include the determination of 

 the heat output of the body. As these measurements have a very direct and 

 important bearing upon the measurements of body material katabolized, a 

 careful inspection of the heat data is of interest. 



The larger portion of the heat given off from the body is measured by the 

 current of cold water which passes through the heat absorbers inside the 

 respiration chamber. From the differences in temperature of the water as it 

 enters and leaves the chamber, and the mass of water, the heat absorbed can 

 be computed. 



Correction for specific heat of water. The measurement of heat by this 

 method involves the use of a varying standard, i. e., the calorie at the different 

 ranges of temperature through which the water is warmed, and it is accordingly 

 necessary to reduce these observed heat values to the standard calorie, which 

 in all of the work with the respiration calorimeter thus far has been the calorie 

 at 20 C. 8 There are not immaterial differences in the specific heat of water 

 at different temperatures. These specific heats have been computed and 

 placed in tabular form elsewhere. 9 



The method of reducing this heat to terms of C 20 is shown in table 12. 

 Thus, in column a is recorded the heat measured as the product of the mass 

 of water and the differences in temperature. In column o, the range of 

 temperature as expressed in degrees centigrade, and in column c the specific 

 heat for these ranges of temperature are shown. By multiplying the heat 

 measured by the specific heat of water at the temperatures used, the heat in 

 terms of C 20 recorded in column d can be obtained. 



6 The calorie used in all measurements discussed in this report is the quantity 

 of heat required to raise 1 kilo of water from 19.5 to 20.5 C. 

 U. S. Dept. of Agr., Office of Exp. Sta. Bui. 63, p. 56. 



