Vol. 6, 1920 PHYSICS: H. H. SHELDON 181 
3 and 4, the same after treatment. This treatment consisted of 3V2 
hours at 1000° C. in a vacuum, kept down by a condensation pump. 
Figure; 1, Hydrogen Figure 2, Nitrogen 
1 
400° C. 
15 hours 
1 
Initial Curve 
2 
400° C. 
8 hours 
2 
500° C. 
15 hours 
3 
400° C. 
20 hours 
3 
700° C. 
9V2 hours 
4 
600° C. 
16 hours 
4 
800° C. 
8 hours 
5 
700° C. 
15 hours 
5 
900° C. 
6 hours 
6 
700° C. 
15 hours 
6 
500° C. 
5 hours 
7 
800° C. 
10 hours 
7 
1000° C. 
1 hour 
8 
800° C. 
9 hours 
8 
700° C. 
8 hours 
9 
900° C. 
5 hours 
10 
900° C. 
5 hours 
11 
900° C. 
10 hours 
12 
1000° C. 
3V2 hours 
13 
f 1000° C. 
1 hour ] 
\ 500° C. 
15 hours J 
14 
500° C. 
20 hours 
