321 



Mr. A. K. Chapman on the 



against the possibility of the other two transverse effects 

 seriously interfering with the accurate determination of the 

 Corbino effect applies equally well here. There is the 

 additional assurance that isothermal conditions were approxi- 

 mately realized by the use of the water-bath with both the 

 magnet and solenoid. 



Unfortunately it is impossible to attain high values of H 

 with such a solenoid as the one used in this research. For 

 that region one must rest content with the curves obtained 

 with the magnet. At low values of H, for various reasons 

 mentioned above, the results of the experiments with the 

 solenoid must be considered much the more trustworthy. 



The Corbino Effect in Bismuth at Low Fields. — In certain 

 metals, notably bismuth and antimony, the Corbino effect is 

 large enough to admit of investigation at low fields. This 

 was done more or less thoroughly for bismuth and roughly 

 for the 1 per cent, alloy of bismuth and tin. It may be 

 observed from fig. 1 that the three points for low fields all 

 correspond approximately to the same value of c. That this 

 is actually the case for this region is shown by the accom- 

 panying table. The value of c up to a flux of 800 lines per 

 square centimetre is constant within the limits of error. 

 While the constant c is of the same order of magnitude as 

 that found with the magnet, there is yet, as in the case of 

 iron, a marked difference between them. It is likely that, 

 as before stated, this is due to the distortion of the field 

 •occurring when the magnet is made use of. 



The Corbino Effect in Bismuth (solenoid). 



H. 



2o/H. 



cxlO 7 . 



41-0 



0027 



116-4 



8-.V8 



0-0276 



1L9- 



136-5 



0-0258 



ill- 



182-6 



0-0268 



11 6- 



269-4 



0-0267 



Ho- 



314-9 



0-0267 



llo- 



397-1 



0277 



119- 



441-6 



0-0272 



117- 



519-4 



0-0271 



117- 



562-5 



0-0270 



116- 



6317 



00269 



116. 



678-2 



0-0267 



i lo- 



736-5 



00272 



rn- 



7865 



0-0266 



315- 



838-2 



00264 



114- 





Mean 



... 115-9 



