April, 1916] Conductivity of Indium and Thallium 



245 



In order to calculate the specific resistance of the indium the 

 specific resistance at 0° C. was taken as 8.37 x 10"'^ ohms. This 

 is the value found by Erhardj who made his observations on 

 indium in the form of wires. Taking this value as known the 

 value of the specific resistance for any other temperature could 

 be at once calculated. In the case of thallium the value by 

 Dewar and Flemingf was assumed to be correct. These 



3-2 



24- 



u 



0.8 



100" 



zoo° 

 Figure 1 



300 



^00 T 



observers found the specific resistance of thallium to be 17.60 

 X lO"*' ohm at 0° C. From this value the other values for the 

 specific resistance were calculated. 



The results of these observations have been given in Table I 

 and have also been plotted in the accompanying figure 1 in which 

 the ordinates are the specific resistances in ohms and the 

 abscissae are the temperatures. Some of the observations were 

 made with increasing and some with decreasing temperature. 

 In each of these cases is seen the characteristic discontinuity in 

 the curve at the melting point of the metal. In each of these 



t Erhard, W. A., 14 p. 504 (1881). 



JDewar and Fleming, Phil. Mag. (o) 36, p. 271 (1893). 



