104 HISTORY OF GALVANISM. 



magnetic by heating one part of it. This discovery 

 of thermo-electricity was made by Professor Seebeck 

 of Berlin, in 1822, and prosecuted by various per- 

 sons; especially by Prof. Gumming 1 of Cambridge, 

 who, early in 1823, extended the examination of 

 this property to most /)f the metals, and determined 

 their thermo-electric order. But as these investi- 

 gations exhibited no new mechanical effects of elec- 

 tromotive forces, they do not now further concern 

 us ; and we pass on, at present, to a case in which 

 such forces act in a manner different from any of 

 those already described. 



1 Camb. Trans, vol. ii. p. 62. On the Developement of 

 Electro-Magnetism by Heat. 



