THOMPSON AND LOMBARD. — NITROGEN IN CALCIUM CYANAMIDE. 253 



Temperature measurements of the charge were therefore made with 

 different values of the current in the lamp of the Wanner pyrometer, 

 and the correct value, with its corresponding temperature, was deter- 

 mined subsequently from Table I. 



Apr. 28. 



Some nitrogen was pumped out, in order not to use up all the 

 carbide. 



1.52 p.m. 8.52 264.0 



4.45 " 8.52 267.4 



Apr. 29. 12.35 " 8.52 267.8 



2.22 " 8.53 270.0 



Here the pressure had become nearly constant, so nitrogen was 

 admitted. 



2.25 p.m. 8.48 277.0 



4.45 " 8.52 273.3 



The equilibrium pressure is therefore between 270 and 273, or 271.5 

 millimeters of mercury. The temperature, determined as explained 

 above, was 1263° C. 



E.Tperiment 6. 



A fresh charge of 33.7 grams of carbide was used in the following 

 experiment. 



Time. Kilowatts. Pressure. 



Ma^ 11. 2.55 p.m. 7.65 281.7 



4.05 " 7.66 224.0 



4.37 " 7.66 223.6 



The pressure had become nearly constant, so nitrogen was admitted. 



4.45 p. m. 7.66 226.3 



5.10 " 7.66 225.1 



Maij 12. 12.40 " 7.70 218.5 



1.00 " 7.00 222.7 



2.22 " 7.58 223.0 



Nitrogen was again pumped out. 



2.23 p.m. 7.58 214.1 

 4.30 " 7.52 224.7 



3Iai/ 13. 1.45 " 7.56 224.6 



2.45 " 7.61 223.5 



