364 PIONEERS OF SCIENCE IN AMERICA. 



pense to the senders, and similar publications from abroad are 

 distributed to their intended recipients. From this system of 

 exchanges, not only in publications but in objects of interest, 

 the great National Museum has sprung a child grown larger, 

 in buildings at least, than its mother. The Library of Congress 

 has been increased from the same source, so that, while at 

 Henry's death the original sum of the bequest remained intact, 

 the objects desired by the opponents of his policy, have been 

 secured. A general index of memoirs on scientific subjects 

 from 1800 was one of Henry's ideas which could not be carried 

 out with the part of the income of the Institution available, but 

 it has been fortunately given form in the great Royal Society's 

 Catalogue of Scientific Papers, due credit for the suggestion 

 being given in the preface to that monumental work. The pub- 

 lications actually issued by the Smithsonian in the course of 

 Henry's administration comprise, first, over one hundred impor- 

 tant original memoirs, forming twenty-one large quarto volumes 

 of the Smithsonian Contributions to Knowledge, most of them 

 universally recognised as authorities on their respective topics; 

 and, second, fifteen octavo volumes of Smithsonian Miscella- 

 neous Collections, more technical than the Contributions, to 

 which should be added the thirty octavo volumes of annual 

 Reports, in which the secretary gave an account of his stew- 

 ardship. In 1870 the Regents testified to their appreciation of 

 his service by giving him a leave of absence, with an allowance 

 for expenses, in order that he might take a European trip. He 

 spent four and a half months abroad, being everywhere re- 

 ceived with consideration, and hearing abundant commenda- 

 tions of the institution which he represented. 



Although no part of his duty as director of the Smithsonian, 

 Prof. Henry was frequently called upon to use his scientific 

 knowledge and ability in the service of the Government. On 

 the establishment of the Lighthouse Board, in 1852, he was 

 appointed one of its members, and in 1871 became its chair- 

 man. The advancing cost of whale oil soon made a more 

 economical illuminant necessary. By a series of thorough 

 tests he demonstrated that lard oil, which had been pronounced 

 unsuitable, was really superior to the colza or rape-seed oil 

 used in France, and the sperm oil heretofore used. Kerosene 

 had not yet become a reliable commercial article. Prof. Henry 

 also investigated the comparative advantages of the steam 



