1897. 



PETROLEUM AND NATURAL GAS. 93 



Prof. Peckliam, of Ann Arbor, read a paper on " The 

 Nature and Origin of Petroleum." 



A communication from Mr. David T. Da)^-was read, en- 

 titled "A Suggestion as to the Origin of Pennsylvania Petro- 

 leum.'' 



The Secretary read by title two papers by Prof. Phillips on 

 " The Genesis of Natural Gas and Petroleum," and on " The 

 Occurrence of Petroleum in the Cavities of Fossils." 



Prof. Mabery then presented his views on the composition 

 of Petroleum. 



Eemarks in discussion were then made by Dr. Sadtler, Mr. 

 Wharton, Prof. Mabery and Prof. Peckham, and Prof. Ma- 

 bery closed the discussion with a warm recognition of Dr. 

 Sadtler's and Prof. Peckham's work. 



THE GENESIS AND CHEMICAL RELATIONS OF PETRO- 

 LEUM AND NATURAL GAS. 



BY SAMUEL P. SADTLER, PH.D. 



{Read February 5, 1897.) 



Of natural products in the mineral kingdom, few have excited 

 the interest of geologists and chemists in the same degree as what 

 in the broad sense we call bitumen. Occurring as it does in solid, 

 liquid and gaseous condition in almost all parts of the world, and 

 in amount varying from the slight bituminous impregnation of 

 shales, limestones, sandstones, and other rocks to the great petro- 

 leum deposits which are now worked in this country and Russia, it 

 has furnished ever-new and interesting material for scientific study 

 and discussion. 



This widespread occurrence and the varied forms under which it 

 is brought to our attention would be quite sufficient to explain its 

 interest from a geological point of view, but when we add to this 

 that in its main forms of production, petroleum and natural gas, 

 chemists find represented those simplest forms of organic compounds, 

 the hydrocarbons, we have an additional element of interest. 



