CALCULATION OP RESULTS. JI 



of carbon dioxide includes a water-absorber in addition to the three soda- 

 lime cylinders, the volume of air in this absorber and connections, i. <?., 

 14.60 liters, must be taken into consideration. 



VOLUME OF REMAINDER OF AIR SYSTEM. 



The volumes of the mercury valves at the exit end of the absorbing 

 system and the pipes back to the calorimeter are computed as before. 

 This volume is equal to 41.08 liters. The volume of the pans is a 

 fluctuating one, and consequently considered under the head of fluctu- 

 ating volumes. 



VOLUME OF OBJECTS IN THE CHAMBER NOT PERMANENT. 



The apparent volume of air in the respiration chamber (p. 69) of 

 5,008.4 liters is diminished by the volume of the objects in the calo- 

 rimeter. This may affect the calculation of results in two ways. In 

 the first place, the total volume of air in the system is diminished by 

 the presence of articles inside the calorimeter chamber. In an alcohol 

 check experiment (see p. 96) this reduction in volume of the air is a 

 constant one, there being no change from the beginning to the end of 

 the experiment, since neither the window nor the food aperture is 

 opened during that time, and the volume of alcohol inside is the same 

 at the beginning and the end of each experimental period. Under such 

 conditions, therefore, the only influence of the presence of material 

 inside the chamber is that of diminishing the apparent volume of air. 

 When a metabolism experiment with man is in progress, however, there 

 may be very material differences in the apparent volume of air in the 

 system, due to the fact that the quantity of material in the chamber is 

 constantly varying by passage into or out of the food aperture. (See p. 

 75.) Under these conditions a second influence may be exerted by 

 the presence of material inside the chamber, i. e. , a fluctuation in the 

 actual volume of gas present. 



VOLUME IN AN ALCOHOL CHECK EXPERIMENT. 



In alcohol check experiments, the volume of the air in the chamber 

 is increased as the inner door of the food aperture remains open, thus 

 adding 4. 63 liters of air, the volume of the food aperture, to the system. 

 In addition to the volume of the permanent fixtures, 9.24 liters, it is 

 necessary to deduct the following volumes, in liters : Lamp, 0.2 (see fig. 

 22) ; alcohol in lamp, 0.4 ; three iron stands for holding the lamp and 

 mirror, 0.95 a total of 1.55 liters. The total volume of air in the sys- 

 tem under these conditions is therefore 5,008.4 + 4.63 (1.55 + 9.24) 

 = 5,002.24 liters. 



