1895 - 96 .] Dr Beattie on Thermo-electricity in Bismuth. 155 
this connection will also be found in a number of other substances 
whose thermo-electric position is extreme. Selenium, for instance, 
which lies beyond tellurium, ought to have an extremely large 
positive transverse effect. Copper pyrites, arsenical pyrites, lead 
glance, iron glance, should have a large negative transverse effect ; 
similarly, those sulphur compounds of the metals whose thermo- 
electric position is so peculiar should also have a large negative 
effect. 
