[boyle] 



TENSILE STRESS ON ELECTRICAL RESISTANCE 



18S 



Copper. 



This specimen of copper must have been of only moderate purity, 

 for the value obtained for its speciHc resistance was higher than that 

 given for very pure copper. Figs. 7 and 8 show the result obtained : — 



.12 





INCRC/^SC P£R CC/VT 



I O 

 STRCTCH. 



Fig 7. 



