THERMO-ELECTROMOTIVE FORCE, PELTIER HEAT, AND 

 THOMSON HEAT UNDER PRESSURE. 



By p. W. Bridgmax. 



Received October 5, 1917. 



CONTENTS. 



Page 



Introduction 269 



Apparatus and Experimental Methods 272 



Methods of Computation 282 



Detailed Data 284 



Tin 284 Nickel 327 



ThaUium 289 Cobalt 331 



Cadmium 293 Iron 334 



Lead 297 Palladium 343 



Zinc 301 Platinum 346 



Magnesium 305 Molybdenum 353 



Aluminum 308 Tungsten 356 



Silver 316 Bismuth 360 



Gold 319 Constantan 365 



Copper 323 Manganin 370 



Effect of Tension on Thermo-Electric Quality .... .... 374 



Nickel 376 Aluminum 377 



Copper 376 Brass 377 



Iron 377 Manganin 378 



Dependence of Thomson Heat on Temperature Gradient .... 378 



General Survey of Results 380 



The Entropy of Electricity 383 



Conclusion and Summary 384 



Introduction. 



The effect of pressure on the electrical resistance of a large number 

 of metals over a considerable range of pressure and temperature 

 (0° to 100° C, and to 12000 kg/cm^) has formed the subject of two 

 recent papers.^ The facts there presented suggested new points of 

 view concerning the mechanism of electrical conduction in metals. 

 Since, however, conductivity is only one of the electrical properties 

 of metals, we would expect that information regarding all electrical 



1 P. W. Bridgman, Proc. Amer. Acad. 62, 571-646, 1917. 

 Phys. Rev. 9, 269-289, 1917. 



