SOURCE OF BITUMEN IN THE OH/0 SHALE. 349 



GEOLOGY AND GEOGRAPHY. 



REPORT OF PROF. E. T. COX. 



Prof. E. T. Cox, Vice President of the section, was formerly Professor of 

 Geology in the State University of Indiana, and removed to San Francisco four 

 years ago, since which he has traveled and made extensive explorations in Ari- 

 zona, and latterly in Senora, Mexico. 



Prof. Cox stated to the section that the labor he had been engaged in during 

 the past four years had been of a character to take him away from practical geo- 

 logical work. For the last year he had been a portion of the time in Mexico, out 

 of reach of all scientific journals and libraries from which to obtain the necessary 

 information to make a regular address such as would represent the progress of 

 geology during the present year, but at the request of the members present he 

 gave them a familiar e^-iempore address on the general character of the geology 

 of the Pacific States the mineral deposits of the region, placer gold mining, and 

 gave some account of the anthracite coal field which exists 120 miles east of 

 -Guymas, on the Zaqui River, in Sonora, Mexico. 



BITUMEN IN THE OHIO SHALE. 



Prof. Edward Orton, of Columbus, Ohio, read a paper entitled "A Source 

 -of the Bituminous Matter in the Ohio Black Shale." Dr. Orton said that the 

 three beds of bituminous shale of Huron, Cleveland and Newbury have many 

 points of structure and history in common. They are all marine in origin, and 

 they were all formed in quiet waters, and not upon shore lines. They carry from 

 -8 to 22 per cent of organic matter, and this gives them their color and renders 

 them combustible to a more or less degree. There is scarcely a summer in 

 which some of the shale banks of southern Ohio do not take fire. It is this same 

 organic matter obviously to which they owe their character as oil producing 

 •shales. They have already been turned to account for the production of oil, 

 and it is scarcely to be doubted that the great stock of carbon which they con- 

 tain will at some time be utihzed by man. This organic matter has been referred 

 both to animal and vegetable sources for its origin, and both of these divisions of 

 the living world have certainly contributed to it. He considered this accumula- 

 tion of bituminous matter as the result of the growth of sea-weeds in marine ba- 

 sins. In examining in a microscope some borings from a well he found at depths 

 of 996, 1016 and 1044 feet, a number of minute translucent discs, resinous in ap- 

 pearance and unmistakably organic in origin. On examining the black shale 



