MancJicstcr Memoirs, Vol. Iv. (191 1), No. 1*^. 



radiation and other causes before the galvanometer came 

 to rest. 



It was found that a deflection of i mm. on the 

 galvanometer scale was produced by a potential difference 

 of 0*024 1 micro- volts at its terminals. The thermo- 

 electric value of copper and eureka being taken as 40 

 micro-volts per degree Centigrade, it was found that 

 I mm. deflection corresponds to ooooiQi'C. 



The curve in Fig. 4 is a typical example of the thermal 



+ ooz 



fj 



I 



- 00^ 



O OS /o /S 



Fig. 4. 



effects obtained by the authors, the neutral point, where 

 neither heating nor cooling takes place, occurring at a 

 tension of 19 lbs. per square inch. The other curve in the 

 same figure is obtained by calculations based on Chauveau's 

 hypothesis. The calculations are based upon a length 

 of I cm. 



Initial volume of i cm. length =0*4 c.c. 



Specific Heat =0'4i5 (Joule). 



Specific Gravity =0965 (Joule). 



