REPORT OF THE SECRETARY. 19 



The .series of Contributions to Knowledge arc intended to 

 record results of original researches in science, for the 

 ina'ea8e of knowledge. In this series there has been put in 

 course of publication during the 37car a memoir l)y Dr. Carl 

 Barus upon experiments in ionized air, a work which, as 

 mentioned above, was carried on with a grant from the 

 Hodgkins fund. 



To the series of Miscellaneous Collections there have been 

 added a ))ibliography of chemical dissertations compiled })y 

 Dr. Bolton, and an article on the ''Cheapest form of light," 

 the latter being a I'eprint of a paper by the Secretary and 

 Mr. Very, originally pu])lished in the American Journal of 

 Science, for which there has l)een a contiiuied demand. 



There have also been added to the Miscellaneous Collections 

 two volumes containing the legislative history of the Institu- 

 tion from the announcement of the original bequest in 1835 

 to the year 1899. It is prepared ])y W. J. Ilhees, of this 

 Institution. This work was published also in a Congressional 

 edition. 



As year by year the publications of the Institution and of 

 its bureaus are increased in numl)er it is believed that its 

 influence, not only in the "increase'' Init in the " diffusion " of 

 knowledge, is felt in a greater degree. This is manifest by 

 the greater popular demand for publications, particularly the 

 General Appendix to the Secretary's Annual Reports, in 

 which the aim has been to consider the diffusion of knowledge 

 among the masses of the people, and to create a desire for a 

 better understanding of the important relations that exist 

 between scientific studies and the needs of our daily life. 



It will l)e remembered that under the general printing law, 

 besides the limited document edition of the Smithsonian Re- 

 port distributed to certain designated depositories, only '3,0nO 

 copies are now published by Congress for the use of its mem- 

 bers, and 7,000 copies for distribution by the Institution, but 

 it is earnestly to be hoped that a larger edition will be author- 

 ized to correspond with the increased popular demand. 



With regard to this larger edition, it may be said that it was 

 a custom, introduced by the first Secretary of the Institution, 

 Joseph Henry, of honored memory, to give a certain number 

 of timely articles of an instructive ))ut wholly popular and 

 nontechnical character in the General Appendix to the Secre- 

 tary's Report. 



