AND STRAIN ON THE ACTION OF PHYSICAL FORCES. 
103 
Experiment XXXIII. 
A wire of annealed copper, 8 feet in length and ‘095 centim. in diameter, hammered 
transversely throughout its entire length. 
Total increase of 
length per cent, produced 
by hammering 
= A. 
Total increase of 
specific resistance per cent, 
produced by hammering 
= B. 
Ratio of B : A. 
1-89 
+ ■017’ 
•009 
31] 
+ ■174 
■056 
5-95 
+ •009 
•002 
9-66 
-•209 
-•022 
1676 
-■530 
-•032 
Experiment XXXIV. 
A wire of annealed iron, 8 feet in length and '092 centim. in diameter, hammered 
transversely throughout its entire length. 
Total increase of 
length per cent, produced 
by hammering 
= A. 
Total increase of 
specific resistance per cent, 
produced by hammering 
= B. 
Ratio of B : A. 
2-04 
-0-082 
-•040 
3-94 
-1-035 
-•263 
10-27 
+ 0-554 
+ -054 
12-31 
+ 1-283 
+ •105 
In the next table will be found a series of curves showing the change of specific 
resistance produced by hammering on the metals iron, copper, zinc, aluminium, German- 
silver, and platinum-silver. The abscissae showing the percentage alteration of specific 
resistance are on a scale of '05 per cent, for 1 m illim ., and the ordinates representing 
the increase of length per cent, are on a scale of '25 per cent, for 1 millim. 
