EFFECT OF TENSION ON CERTAIN ABNORMAL METALS. 



53 



The range of tension through which the wire has been accommodated 

 has a sHght effect on the character of the loop; the tension of the 

 minimum increases somewhat as the range is increased. 







200 



400 600 



Tension in Grams 



Nickel 



1000 



FiGTTRE 1. The decrease of resistance of Nickel in arbitrary units plotted 

 against the tension in grams at three different temi)eratures. In each case the 

 higher curve of the loop is that obtained with decreasing tension. One arbi- 

 trary unit of resistance corresponds to a decrease of 0.0345 per cent. The 

 cross section of the wire was such that a load of 1000 gm. means 1900 km/cm^ 



There is a very hirge effect of temperature on the sliape of the loop. 

 I made measurements at 0°, 30°, and 95°. The minimum becomes 



