Stated Meeting, January 16 411 Stated Meeting, February 6 413 Stated Meeting, February 20 415 On the Oil sand of Bradford, MoKean County. By C. A. Ashburner. Obituary notice of J. W. Harden. By J. P. Lesley 422 Astronomical approximations, II, III. By P. E. Chase 425 Relations of the Crystalline rocks of Pennsylvania to the Silurian By C. E. Hall. (With Plate VI.) 485 An Account of an Old work on Cosmography. By //. Phillips, Jr.. 443 On a New Synthesis of Saligenin. By W. ll. Greene, M.D 451 On the Foramina perforating the posterior part of the Squamosal bone of the Mammalia. By E. I1. Cope 452 Biographical notice of Joseph Henry. By Fairman Rogers 401 The Timucua language. By A. S. Gatschet... 4fi5 A Mirror for Illuminating opaque objects for the Projecting Micro- scope. By Persifor Frazer, Jr 50:! Three methods and Forty-eight solutions of the Fifteen Problem. Stated Meeting, January 2, 1880. Present, 5 members. President, Mr. Fraley, in the Chair. A letter accepting his appointment to prepare an obituary notice of the late M. Michel Chevalier, was received from Mr. Moncure Robinson, dated Dec. 22, 1879. A letter of envoy was received from the London Meteorological office, dated Dec. 1879. A letter requesting a copy of Proc. No. 100, to complete a set was received from the Central Austalt fur Meteorologie, dated Vienna, Dec. 4,1879. A letter respecting exchanges of specimens was received from Mr. H. B. Dawson, dated Morisania, N. Y., Dec. 5, 1879. Donations for the Library were received from the Prussian Academy; Revue Politique; London Astronomical, Geographical and Meteorological Societies, and the Cobden Club; the Royal Geological Society of Ireland; the Massachusetts Historical Society; the Boston Society of Natural History ; the American Chemical Society; Mr. A. R. Grote; the Franklin Institute; American Journal of Mathematics; the North American Entomologist; the U. S. Treasury Department; the Botanical Gazette; the Ministerio de Fomeiito of Mexico, and Mr. S. H. Scudder. A communication on the Velocity of Light, by P. E. Chase was read. A paper entitled " An account of an old work on Cosmography, by Mr. Henry Phillips, Jr." was postponed to be read at the next meeting. A paper on the relation of the crystalline rocks of Southeastern Pennsylvania to the Silurian limestones, and on the Hudson river age of the Hydromica schists (with map and specimens), by Mr. Charles E. Hall, of the Geological Survey, was postponed to be read at the next meeting. PROC. AMEB. PHILOS. SOC. XVIII. 105. 3A. PRINTED MARCH 30, 1880. The report of the judges and clerks of the annual election for officers of the Society was read, and the following named persons were declared duly elected to be the officers for the ensuing year: President. Eli K. Price, Vice-Presidents. P. E. Chase, Secretaries. G. F. Barker, J. P. Lesley, Councillors for three years. R. E. Rogers, Robert Bridges, Oswald Seidensticker, Richard Wood. Curators. Treasurer. Pending nominations Nos. 885 to 892 were read. Stated Meeting, January 16, 1880. A letter of acknowledgment was received from the R. Academia dei Lincei, Dec. 16, 1879 (102, 103). Letters of envoy were received from the U. S. Department of the Interior, Jan. 2; the U. S. Naval Observatory, Jan. 16; and Dr. B. A. Gould, Director of the Argentine Observatory at Cordova, S. A. Donations for the Library were received from the Geological Survey of Japan; the Russian Academy; the Zoologischer Anzeiger; M. Delesse, and the Revue Politique of Paris; London Nature; the Museum of Comparative Zoology at Cambridge; the Canadian Naturalist; Harvard Observatory; Silliman's Journal; the Scientific American; the Numismatic Society; the Journal of Pharmacy; the Cincinnati Natural History Society ; the Botanical Gazette; the Bureau of Education; the Geological Survey of the Territories; the Fish Commissioners; the Department of the Interior; General Wheeler ; and the Mexican Meteorological Bureau. The death of Dr. Jacob Bigelow, at Boston, Jan. 10, 1879, aged 92, was reported. Mr. Phillips read an elaborate description of his latin copy of the curious Cosmography of Sebastian Munster, who was born 1489, and died at Basle, circa 1552. Mr. Hall exhibited his provisionally colored map of south-eastern Pennsylvania, from Trenton westward to and across the Susquehanna River, and discussed the age of the Philadelphia rocks on his hypothesis of their metamorphism, considering them Silurian, and perhaps in part Devonian. Mr. Rand, Prof. Frazer and Mr. Lesley took part in the |