Fig. 1. — Schematic diagram of the Atwater-Rosa-Benedict respiration calorimeter. 



Ventilating System: 



2 , Oxygen introduced as consumed 

 by subject. 



3, H2SO4, to catch moisture given 

 off by soda lime. 



2, Soda lime to remove CO2. 



1, H2SO4 to remove moisture given 



off by patient. 

 Bl., Blower to keep air in circulation. 

 Indirect Calorimetry: 

 Increase in weight of H 2 C< 04 (1) = 



water elimination ol subject. 

 Increase in weight of soda lime (2) + 



increase in weight of H2SO4 (3) = 



CO2 elimination. 

 Decrease in weight of oxygen tank 



= oxygen consumption of subject. 

 Heat-Absorbing System: 



A, Thermometer to record temper- 

 ature of ingoing water. 



B, Thermometer to record temper- 

 ature of outgoing water. 



measuring 



measuring 



V, Vacuum jacket. 



C, lank for weighing water which 

 has passed through calorimeter 

 each hour. 



W, Thermometer for 

 temperature of wall. 



Al, I hermometer for 

 temperature of the air. 



R, Rectal thermometer for measur- 

 ing temperature of subject. 

 Direct Calorimetry: 



Average difference of A and B X 

 liters of water + (gm. water 

 eliminated X 0.586) =>= (change 

 in temperature of wall X hydro- 

 thermal equivalent of box) =*= 

 (change of temperature of body X 

 hydrothermal equivalent of body) 

 = total calories produced. 

 Th, thermocouple; Cu, inner copper 



wall; CU2, outer copper wall; E, F, 



dead air spaces. 



350 



