NATIONAL ACADEMY OF SCIENCES. 



and change. Moreover, he was confident that he could render a 

 greater service to geological science by pursuing the theoretical 

 researches into its deeper problems, for which the physical 

 laboratory he had established would in time furnish the neces- 

 ssltj data, than by devoting his time and strength to administra- 

 tive duties. Financial considerations doubtless had some weight 

 also, for under the new law his official position shut him out 

 from any professional remuneration beyond his salary, and that 

 was not sufficient to enable him to meet the obligations he felt it 

 incumbent upon him to assume for others. 



During the remaining twenty years of his life much of his 

 time was necessarily given to private professional work, either in 

 personally managing and developing mining properties or acting 

 as adviser for others. In this work his ambition was to accumu- 

 late sufficient capital to enable him to pursue unrestrainedly 

 the necessarily expensive experiments needful for the carrying 

 out of his chosen line of investigation, and to insure the comfort 

 of those depending upon him. Freed from the confinement and 

 responsibilities of the administration of a great survey, he was, 

 moreover, now able to devote more of his time to the cultivation 

 and indulgence of his pronounced literary and artistic tastes; 

 but his scientific investigations, though of necessity frequently 

 interrupted, were ever present in his mind, and never, as some 

 have erroneously assumed, abandoned. 



In 1882, being called to London on business connected with 

 some large Mexican mining companies, of which he was presi- 

 dent, he came into familiar converse with the leaders o*f the 

 scientific and literary circles of that great intellectual center, to 

 whom his work was already well and favorably known and his 

 charming personality soon endeared him. 



The greater part of the next two years was spent there and 

 in traveling extensively on the continent. While he naturally 

 came into contact with most of the prominent scientific men in 

 Europe and recalled with special pleasure his intercourse with 

 Sir William Thomson (now Lord Kelvin), whose investigations 

 into terrestrial physics had early attracted his attention and ex- 

 cited his admiration, he was perhaps even more widely known 

 and admired in Europe for his literary and social qualities and 

 as a connoisseur of art. 



46 



