254 PROCEEDINGS OF THE AMERICAN ACADEMY. 



The pressure had become nearly constant at 224 millimeters, so 

 nitrogen was admitted. 



Time. Kilowatts. Pressure. 



2.55 P. M. - 7.61 236.0 



5.05 " 7.40 224.7 



The mean temperature was 1223°, with the current in the lamp of 

 the Wanner pyrometer 6.4 units. The equilibrium pressure was deter- 

 mined twice from each direction, and was found to be 224 millimeters. 



Experiment 7. 

 The following experiment was made with the same charge as in 6. 



Absorption was taking place very slowly. In order to see whether 

 313 or 305 was nearer the true value, nitrogen was pumped out. 



4.34 p.m. 8.71 309.0 



4.55 " 8.71 310.3 



