Clark.] Kg [June. 



mington Institutes ; the Minister of the Interior at Harlem ; 

 the Museum of Natural History, and the Geographical So- 

 ciety at Paris ; the Royal, Royal Geographical, and Chemi- 

 cal Societies at London ; the publishers of the Medical News 

 of Philadelphia ; Messrs. J, S. Morris of Baltimore ; S. 

 Shellabarger of Washington ; F. Leypoldt of Philadelphia ; 

 Dr. Englemann of St. Louis ; and the State of Wisconsin. 



On recommendation of the special committee to which it 

 was referred, Dr. Hayden's memoir on the Lidian Tribes of 

 the Missouri River was, on motion of Dr. Bache, ordered to 

 be published in the Transactions. 



The committee on Mr, Prettyman's communication, re- 

 ported verbally through its Chairman, Prof. Cresson, that it 

 had had an interview with Mr. Prettyman, who asked leave 

 to withdraw his communication. On motion, leave was 

 granted. 



A suite of coal oil specimens was offered for the examina- 

 tion of the members present. Mr. Heber R. Clark, who was 

 present, being invited to give a description of the coal oil 

 localities with which he was most familiar, and from which 

 he had himself collected the various oils which he exhibited, 

 communicated very interesting and detailed information re- 

 specting their geological and statistical character. 



Mr. Clark said that the principal part of the specimens, and com- 

 monly those of the lightest color, were from various borings around 

 Edenburg, in Lawrence County, Pennsylvania, and in the same 

 valley of the Mahoning, within the Ohio State line. Many were 

 from the Slippery Rock Creek Valley. A number were from Oil 

 Creek, and the neighborhood of Titusville in Northwestern Pennsyl- 

 vania. One or two were from Mecca in Northeastern Ohio, and 

 from Kentucky; the last being thick and black like tar. 



The Edenburg " Continental Boring" was sent down through 80 

 feet of so-called drift; then through 200 feet of sandstones and 

 shales, with a layer of black, fetid shale at the bottom, fi-om which 

 the gas blew off violently ; then through 45 or 50 feet of the " First 

 White Sandstone," with gas in its crevices (this sandrock is said to 

 thin out eastward) ; then through 40 or 50 feet of shales and slates 

 charged with gas and oil ; then through 75 or 80 feet of the " Second 

 White Sandstone," softer, coarser, and harder than the first, and full 



