The E"lecteical Resistance and TE:NrPEEATURE Coefficient 

 OF Ice. — By J. H. L. Johnstone, B. Sc, Dalhoiisie 

 University, Halifax, I^. S.* 



Read 13th May, 1912. 



The following investigation was iirst begun in January, 

 1911, with the object of determining the resist ence of ice. 



A great many difficulties were subsequently met with, 

 which resulted, as will be seen, in a modification of the original 

 methods of experiment; and several other problems appeared, 

 closely connected with the one treated of in this paper, the 

 chief one of which is the effect of polarization, and its nature 

 as related to ice. The latter problem is to be investigated fully 

 at a later time. 



Dr. H. L. Bronson, when working in the Physical 

 laboratory at McGill University, noticed the peculiarities 

 connected with this problem and as a result this work was 

 undertaken, with his guidance, by the writer. 



The only measurements of the resistance of ice, that could 

 be found after a diligent search, were obtained from a paper 

 by Ayrton and Perry. ^ As these measurements appear to be 

 the only ones published, a brief summary, together with the- 

 results of their work, is given here. 



Arvton and Perrv measured the resistance of ice as follows : 



G/3^ 



Gglvsnoi^eiet^ 



"A/ffondnd Perryi Af/^SraTus 



Fig. 1. 



Fig. 2. 



* Coittribut ions 1 i-om the Science Laboratories of Dalhousie Univer.sity— [Physics^ 

 lAyrton, M. E., and Pe*Ty : Proc. London Phys. Soc, Vol. II, 178, March, 1877. 



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