THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOUKNAL OF SCIENCE. 



[FIFTH SERIES.] 

 APRIL 1884. 



XXIX. On some Experiments illustrating an Explanation of 

 Hall's Phenomenon. By Shelford Bid well, M. A., LL.B* 



[Plate XL] 



IN a recent communication to the Royal Society I attempted 

 to show that the apparent action of a magnet upon an 

 electric current (well known as Hall's Phenomenon) might 

 be completely explained by the operation of mechanical strain 

 and certain Peltier effects. 



My experimental acquaintance with the subject began in 

 July 1883, and I have since devoted a considerable amount 

 of attention to it. But the paper referred to contained only 

 a bald and simple statement of the results at which I finally 

 arrived, little or nothing being added by way of comment or 

 explanation. To my mind, saturated as it was with the matter, 

 it appeared that such a statement afforded in itself over- 

 whelming evidence in favour of the views which I had been 

 led to adopt ; and I believed that when once set forth, how- 

 ever briefly, they could not fail to meet with immediate 

 acceptance. But HaLPs own theory of the phenomenon has 

 for some years been universally recognized as interpreting a 

 well-established law of nature. It seemed to be in complete 

 harmony with the views of Clerk Maxwell as to the existence 

 of a rotatory coefficient of resistance : it has provided a field 

 for investigation to mathematicians of the highest eminence; 

 and it has derived additional interest and importance from 

 the fact that it was believed to point to an intimate relation 



* Communicated by the Physical Society. Head March 8, 1884. 

 Phil Mag. S. 5. Vol. 17. No. 106. April 1884. S 



