SOMETHING ABOUT OIL. 283 



leum in a formation is far from being evidence that it ex 

 ists in large quantities. Observation has shown that it 

 does not exist in large quantities in any formation, except 

 under certain intelligible conditions. Its presence in small 

 quantities is to be expected. 



It is an opinion almost universal among geologists that 

 petroleum has been produced from organic remains. Hence, 

 long before the discovery of the Eozoon in Laurentian rocks, 

 it had been inferred that organic life existed upon our planet 

 during the accumulation of those rocks, because, among oth 

 er reasons, they aiford conspicuous quantities of petroleum. 

 Geologists are somewhat divided in opinion as to whether 

 animal or vegetable organisms have afforded most of the 

 native oil. Little dissent exists, however, from the doc 

 trine that most of the oil occupying the pores and pockets 

 of fossiliferous limestones has been derived from animal 

 bodies, while that saturating shales and arising from shales 

 has had a vegetable origin. As the oil of commerce is prob 

 ably derived from the latter source, it appears that we are 

 to regard our commercial oil as a vegetable product. 



Petroleum and the other hydrocarbons are produced from 

 organic matters Hy distillation in closed vessels. Any veg 

 etable substance is capable of affording them. The refuse 

 of the kitchen may be made to illuminate the mansion. Ar 

 tificial distillation of any of the rocks containing organic 

 remains gives rise to petroleum. Ordinary black shales 

 abound in vegetable matter mostly in a state of comminu 

 tion, and they readily afford large quantities of oil and gas. 

 They are, in fact, distilled on the large scale in some Euro 

 pean countries for the sake of these products. It has also 

 been undertaken in this country, but without favorable re 

 sults economically. Nature herself is engaged in this busi 

 ness, and competition with her is hazardous. Cannel coal, 

 however, which is only a highly carbonaceous shale, was 



