THE HENRY. 149 



that larger field of activity aud usefulness wliicli was offered by the 

 new institution at Washington, to enter which he knowingly, and 

 against the wishes of many of his friends, ahandoned the practically 

 assured prospe<;t of lasting fame as one of the three or four most dis- 

 tinguished physicists of the present century. During these years the 

 work was done which justifies and demands the recognition accorded 

 to it in bestowing upon Henry the high honor of a place in the galaxy 

 of famous physicists whose names will be perpetuated in the metro- 

 logical nomenclature of all modern languages. In nnich of this work 

 he was running on lines parallel to those followed by an English ])hi- 

 losoi)her who is doubtless justly entitled to be considered as the first 

 experimental physicist of the present age. 



Although older by several years than Henry, Faraday began his series 

 of memorable investigations in electricity about the time Henry pre- 

 sented his first papers on the same subject before the Albany Institute, 

 a local scientific society of which he was a member. From this time 

 forward they were often "treading upon each other's heels." In the 

 early thirties great scientific discoveries were not announced in all parts 

 of the world within twenty-four hours of their making, as is done to-day, 

 thanks to tlie labor of these same two i)hilosophers who sixty years ago, 

 owing to infrequent communication across the sea and scanty means of 

 publication on either side, were often ignorant of an im[)ortant advance 

 for some years after it had been made. Henry's innate modesty made 

 him slow to recognize, at least to acknowledge, the value of what he did, 

 and there is no doubt that he lost much in the way of general recogni- 

 tion by his failure to bring the results of his investigations promptly 

 to the attention of the scientific public. Indeed, it was sometimes the 

 urgency of his friends, more jealous than himself of his scientific rei>u- 

 tation, that secured the tardy publication of important papers. At that 

 date, far removed both in space and time from the center of scientific 

 activity, he often contended with the discouraging yet natural and 

 almost necessary fact that some of his finest work had been anticipated 

 by those who had the start of him in time and the advantage in facilities 

 and resources. 



On August 30, 1831, Faraday made his splendid discovery of electro- 

 magnetic induction. Before this time Henry had investigated the con- 

 ditions necessary to the production of a strong magnetic field, and had 

 constructed by far the most iiowerful magnet known u]) to that day. 

 Ignorant of Faraday's work, he planned and began in August, 1831, 

 a series of experiments with a still more powerful magnet, having in 

 view the discovery of a method of producing electricity from magnetivsm 

 which Faraday was then on the eve of making. But, as already stated, 

 his duties in the academy were exacting, and, being interrupted, he 

 was prevented from returning to the subject for nearly a year. In the 

 meantime news of Faraday's discovery had crossed the ocean, a meager 

 account of his results having reached Henr^^ sometime early in the 



