REPORT OF THE SECRETARY. ot 
with 834 plates of illustrations. The aggregate distribution was 
202,671 copies of pamphlets and bound volumes. 
One of the principal functions of the Institution, “the diffusion of 
knowledge,” is accomplished through its publications, which record 
results of original researches, accounts of explorations, the progress 
achieved in science and industry, and general information in all 
branches of human knowledge believed to be of value to those inter- 
ested in the promotion of science and in the welfare of man. The 
series of “Contributions to Knowledge” in quarto form, and the 
“ Miscellaneous Collections,” in octavo, are printed in limited editions 
at the expense of the Institution and distributed chiefly to certain 
large libraries throughout the world where they are available for pub- 
lic reference. The Annual Report, however, is provided for by con- 
gressional appropriations, and the edition is great enough to permit 
its wide distribution. Besides the official report of the Board of 
Regents and the secretary of the general operations of the Institution 
during the year, there is included in the Smithsonian Report a gen- 
eral appendix containing 30 or more original or selected papers illus- 
trating the more remarkable and important developments in scientific 
discovery. 
Tn addition to the three series of works above mentioned pertain- 
ing to the Institution proper, there are issued under its direction (a) 
_ the Annual Report, the Proceedings, and the Bulletins of the Na- 
tional Museum, including the Contributions from the National Her- 
barium; (0) the Annual Report and Bulletins of the Bureau of 
American Ethnology; and (c) the Annals of the Astrophysical Ob- 
servatory, all of which are public documents printed through annual 
allotments by act of Congress. 
Smithsonian Contributions to Knowledge.—The chief characteris- 
tic of memoirs contained in the Contributions to Knowledge is that 
they are discussions of extensive original investigations constituting 
important additions to knowledge. Since the establishment of this 
series in 1848 there have been published about 150 of these memoirs 
in 35 quarto volumes. The most recent of these, reviewed in my last 
report, was the “Langley Memoir on Mechanical Flight,” recording 
the experiments of the late Secretary Langley, resulting in his suc- 
cessful demonstration of the practicability of aerial navigation with 
machines heavier than the air. 
Smithsonian Miscellaneous Collections —Thirty-six papers in this 
series were issued during the year, forming parts of seven volumes, as 
enumerated in Appendix 8. They included some articles by your 
secretary, describing further results of his studies of Cambrian 
fossils, and papers on the usual wide range of biological, geolog- 
ical, and anthropological topics. In this series are included the 
Smithsonian tables, which have become standard works of reference. 
