4Y0 Henry Andreivs Bumstead. 



mann, Weber, and Helmlioltz. The very general form of 

 Helmlioltz's theory appealed to him greatly, and he takes 

 delight in showing how it contains as special cases most 

 of the other theories proposed, including Maxwell's for- 

 mulation of the results of Faraday's researches. Helm- 

 lioltz's attempts to discriminate experimentally between 

 various somewhat discordant view-points did not seem 

 to him very conclusive, but his admiration for Hertz's 

 genius knew no bounds. He lays particular emphasis on 

 Hertz's zeal in following up every unexplained phe- 

 nomenon to its source, mentioning in particular the 

 discovery of the effect of ultra-violet light on the conduc- 

 tivity of the spark gap. His point of view throughout is 

 that of the older British school of physicists, and it is 

 evident that at this date the "ether" was very real to 

 him. 



During the five years following the completion of his 

 doctor's thesis. Professor Bumstead 's heavy teaching 

 schedule left him little time for research. His interest 

 in electrodynamics, however, was always keen, and in 

 1902 he published a short paper in which he showed how 

 Maxwell 's equations completely accounted for an anomaly 

 in connection with reflection of electric waves which had 

 been causing considerable discussion among experimen- 

 talists. If standing waves are set up on a pair of parallel 

 guide wires terminating in a conducting plane at right 

 angles to their length, the node in electric intensity found 

 at the end of the Avires is at a distance from the nearest 

 node on the wire agreeing with the distances between 

 other adjacent nodes. If, however, the conducting plane 

 is removed, the loop to be expected at the free end of the 

 wires is found to be at a distance from the nearest node 

 somewhat less than a quarter wave-length. Bumstead 

 showed that the introduction of a fictitious magnetic 

 conductivity into Maxwell's equations established a close 

 correspondence betAveen this case and the Avell-understood 

 arrangement in which the ends of the parallel conductors 

 are united by a short connecting Avire. 



The year f olloAA^ing the appearance of this paper, there 

 fell on him the sad duty of AA^riting the obituary of his 

 friend and teacher, J. Willard Gibbs. His interest in 

 and knoA\dedge of mathematical physics enabled him to 

 prepare an appreciation of the great physicist AAdiich could 

 haA^e been equalled by few of his contemporaries. Shortly 



