1910 - 11 .] Young’s Modulus under an Electric Current. 249 
Table XIII. 
Field. 
Load in kilos, 
per sq. mm. 
Elongation for 
500 grams. 
No. of 
Observations. 
M. 
14-2 
10-6 
•02954 cm. 
8 
13-67 x 10 11 
13-25 
•02899 
7 
13 93 
15-9 
02907 
8 
13-89 
19-9 
■02952 
8 
1368 
23-8 
•03009 
6 
13*42 
27-0 
•03067 
6 
13*17 
29-1 
•03096 
5 
1305 
27-0 
•03083 
6 
1310 
23-8 
•03027 
7 
13 34 
19-9 
•02971 
7 
13-59 
15-9 
•02889 
8 
13-98 
13-25 
•02885 
9 
14-00 
10-6 
•02954 
9 
13-67 
Table XIV. 
Field. 
Load in kilos, 
per sq. mm. 
Elongation for 
500 grams. 
No. of 
Observations. 
M. 
19*7 
10-6 
•03143 cm. 
8 
12-85 x 10 11 
13 25 
•03151 
6 
12-81 
15-9 
•03159 
7 
12-78 
19-9 
•03161 
8 
12-77 
23-8 
•03185 
9 
12-68 
27-0 
•03197 
10 
12-63 
29-1 
•03205 
9 
12-60 
27*0 
•03195 
8 
12-64 
23-8 
•03177 
7 
12-71 
19-9 
•03177 
6 
12-71 
15-9 
•03166 
8 
12-75 
13-25 
•03145 
8 
12-84 
10-6 
•03143 
8 
12-85 
In concluding this paper, let me pass in rapid review the outstanding 
facts established by the different experiments. In all of them there are 
striking similarities. When the metals are heated by the ordinary method 
the graphs are uniformly straight lines, and there are no irreversible effects 
with rise of temperature. If, however, the rise of temperature be caused 
by current flow the results are more complex, for, when the heating is 
produced in this way, the variation of the modulus depends on the load. 
When this is fairly large the results are similar to those obtained with 
ordinary heating, that is, there are no irreversible effects. But when the 
load is moderate there are great and most important differences. Both the 
