REPORT OF THE SECRETARY. 13 



A quarter of a century has passed since the publication of the third 

 edition of this valuable and elaborate work. The first edition of the 

 Tables was published by the Institution in 1852, comprising 212 pages. 

 Five years later (in 1857) a second edition was published, with careful 

 revision by the author, and the various series of tables were so en- 

 larged as to extend the work to over GOO pages. The third edition was 

 published in 1859, with still further amendments. 



To this volume Dr. Guyot, with untiring industry, has been making 

 constant additions ; and the i)resent issue, projected by him in 1879 (from 

 various delays occasioned by pressing professional occupations, as well 

 as by illness and death in his family), was about four years in passing 

 through the press. Just before completing the last few tables, the esti- 

 mable and distinguished author departed this life, February 8, 1884, in 

 the seventy-seventh year of his age. The completion of the work was 

 intrusted to his able assistant, Prof. William Libbey,jr., who has judi- 

 ciously executed his duties as the final editor of the work. The tables 

 are arranged in seven series. The first series (comprising 15 tables), 

 thermometrical comparisons and conversions; the second series (of 33 

 tables), hygrometrical computations; the third series (of 27 tables), 

 barometrical; the fourth series (of 27 tables), hypsometrical ; the fifth 

 series, geographical tables, including 40 of measures of length (for 

 heights, &c.), 10 of itinerary measures, and 10 of square measures of 

 geographical surface; the sixth series (of 99 tables) for corrections of 

 variations of temperature, &c., at different parts of the earth ; and the 

 seventh series comprising 9 miscellaneous tables. The whole forms an 

 octavo volume (including 25 introductory pages) of 763 pages. 



]S[o. 545. "Proceedings of the Biological Society of Washington: Vol. 

 II." From July 1, 1882, to July 1, 1884. 8vo. 195 pp. 



592. "Bulletin of the Philosophical Society of Washington: Vol. VII, 

 containing the Minutes of the Society and of the Mathematical Section 

 for the year 1884." From January 5, 1884, to December. 20, 1884. 8vo. 

 lix-|-135 pp., or 194 pp. 



594. "Mental overwork and premature disease among public and pro- 

 fessional men." By Charles K. Mills, M. D. Being lecture IX of the 

 "Toner Lectures"; delivered in Washington, D. 0., March 19, 1884. 

 8 vo. 34 pp. 



595. "The Refraction of Sound." By William B. Taylor. A reprint 

 from the Smithsonian Eeport for 1875. 8vo. 12 pp., with 6 figures. 



608. "Report of Prof. Spencer F. Baird, Secretary of the Smithsonian 

 Institution, to the Board of Regents, for the year 1884." 8vo. 98 pp. 



609. "An Account of the Progress in Astronomy in the year 1884." 

 By Prof. Edward S. Holden. 8vo. 55 pp. 



610. "A Review of the Progress of North American Invertebrate 

 Paleontology for the year 1884." A bibliography of publications on 

 the subject for the year. By John Belknap Marcou. 8vo. 20 pp. 



