CONTRIBUTIONS FROM THE JEFFERSON PHYSICAL 

 LABORATORY, HARVARD UNIVERSITY. 



ON ELECTRIC CONDUCTION AND THERMOELECTRIC 



ACTION IN METALS. 



By Edwin H. Hall. 

 Presented by E. H. Hall, Maroh 11, 1914. Received June 12, 1914. 



Introduction. 



Various considerations that I need not at the beginning set forth 

 at length, but some of which will appear later in this paper, have led 

 me to inquire whether we may not have, in the phenomena of electric 

 conduction and of thermoelectric action in metals, the cooperation of 

 electrons in two conditions. One condition, (A), I have conceived 

 of as that of electrons passing from atom to atom of the metal so 

 quickly, perhaps during actual contacts of the atoms, as not to become 

 subject to the laws of gas pressure, the other condition, (B), I have 

 thought of as that of electrons long enough free between the atoms to 

 act according to the gas laws, though, in deference to the argument 

 from radiation, I assume these free electrons to have a smaller kinetic 

 energy of translation than gas molecules would have in a cavity within 

 the metal. 



Sir J. J. Thomson suggested in his Corpuscular Theory of Matter l 

 an action somewhat like that which I imagine for the (.4) electrons, 

 though he seems presently to have abandoned this idea as unneces- 

 sary. 2 But since Thomson discussed the matter new experimental 

 evidence, especially from the behavior of metals at low temperatures, 

 has seemed to lead naturally back to the conception of electrons 

 transmitted directly from atom to .atom in metallic conduction. If 

 we think of the atoms as being, at very low temperatures, in actual 



1 Pp. 49 and 50. " It is easy to see, however, that a current could be carried 

 through the metal by corpuscles which went straight out of one atom and 

 lodged at their first impact in another; such corpuscles would not be free in 

 the sense in which the word was previously used and would have no oppor- 

 tunities of getting into temperature equilibrium with their surroundings." etc. 



2 See Tunzelmann's Electrical Theory, p. 301. 



