CALCULATION OF RESULTS. 



87 



In order to determine the total volume of air in the chamber under stan- 

 dard conditions of temperature and pressure, to the logarithm of volume 

 I-III is added, first, a logarithmic factor for the temperature recorded 

 for the calorimeter to correct the volume of air to standard temperature. 

 As the temperature fluctuations are all within 1 degree, a table has been 



prepared giving the standard fluctuation represented by the formula - , 



in which t is the temperature of the calorimeter. The correction for pres- 

 sure has also been worked out in a series of tables and the logarithmic 



factor here corresponds to the ratio x . ' , in which p is the observed ba- 

 rometer. The logarithm of the total volume is recorded as a result of the 

 addition of these three logarithms enumerated, and from this logarithm 

 is expressed the total volume of air in liters. Deducting the sum of the 

 values (a) and (&) from the total volume leaves the volume of oxygen plus 

 nitrogen. 



The calculation of the residual volume of nitrogen and the record of the 

 additions thereto was formerly carried out with a refinement that to-day 

 seems wholly unwarranted when other factors influencing this value are 

 taken into consideration. For the majority of experiments the residual 

 volume of nitrogen may be considered as constant in spite of the fact that 

 some nitrogen is regularly admitted with the oxygen. The significance of 

 this assumption is best seen after a consideration of the method of calcu- 

 lating the amount of oxygen admitted to the chamber. 



RESIDUAL SHEET 



No. 1. 



Calculation of residual amounts of nitrogen, oxygen, carbon dioxide and water-rapor 

 remaining in chamber at 8.10 A. M., June 24, 1909. 



Residual at end of Prelim, period. Exp. : Parturition. No 



Subject: Mrs. Whelan. Calorimeter: Bed. 



Barometer, 766.95 mm. 

 Temp, cal., 20.08 °C 



Apparent Volume of Air 

 I containing H,0 716. liters 



I -II " CO, 731. " 



I - III " O+N 766. " 



Log. wt. H,0 in residual 

 .0816 = 91116 



Log. I = 86431 



76647 = 6.83 gms. HoO 

 Gms. to liters. 09462 



(a) 86009 = 7.26 1. H 2 

 Log. wt. CO, in residual 



0423 = 62634 



Log. I-II = 86392 



49026 = 3.09 gms. CO, 

 Gms. to liters, 70680 



(b) 19706 = 1.57 1. CO, 



Miscellaneous Calculations 



= 138.67 1. 



