TEMPERATURE COEFFICIENT OF ICE. — JOHNSTONE. 



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Fig. 3. 



circuit, tlie resistance of the sample of ice was calcnlated from 

 these data, and from this, the speciiic resistance of the ice. 

 This was done for several temperatures. 



A great difficulty was encountered in determining the 

 actual value of the current passing through the ice. Ayrton 

 and Perry were troubled greatly by polarization effects which, 

 at that' time, they were unable to determine the nature of. As 

 they could not eliminate this effect, which wull be shown to be 



