SOURCE OF THE HYDROCARBONS 253 



given a rational and consistent explanation under the new. Like the 

 substance of air and ocean, the material of the hydrocarbons is all 

 primarily derived from the earth's interior and the great localizations of 

 bituminous matter, specially in volcanic districts, are probably of imme- 

 diate derivation from subterranean sources. A few of the facts which 

 discredit the organic theory and confirm the volcanic theory may be 

 marshaled as follows : 



1. The occurrence of great quantities of graphite in ancient gneisses 

 and in eruptive rocks. 



2. The occurrence of liquid carbon dioxide in the crystalline rocks in 

 notable quantities. 



3. The general occurrence in great abundance of hydrogen and hydro- 

 gen compounds in volcanic emanations, the same being true of carbon 

 dioxide. 



4. The frequent occurrence of mofettes or carbon dioxide springs, with 

 constant flow, prevailingly in volcanic regions. Enormous quantities 

 of this gas are exhaled in some localities. The Death valley in Java 

 and the Grotto del Cane near Naples have already been mentioned, and 

 many other examples could be cited. Bischof estimated that the 

 volume of carbon dioxide evolved in the Brohl Thai amounted to 

 5,000,000 cubic feet, or 300 tons, in one day. 



5. The immense deposits with extreme localization of petroleum, as at 

 Baku, and of asphaltum as in Pitch lake, in regions of volcanism. 



6. The association of petroleum with heat and solfataric action, as 

 in Louisiana, Texas, and California. 



7. The occurrence of solid hydrocarbons, as gilsonite, ozocerite, and 

 albertite, in vein systems like ore bodies, and reaching to great depths. 



8. The capricious occurrence of gas and oil in all geologic horizons, 

 and usually with no clue to their derivation. 



9. The localization of oil or gas in strata which are otherwise barren 

 in the same material, thus proving its foreign origin. 



10. The failure to discover any rocks which have certainly lost a 

 carbonaceous content. 



Here are only ten counts in an indictment which could be extended. 

 Doubtless there are hydrocarbon accumulations from organic sources. 

 Like other natural products, their origin and history are complex ; but if 

 the organic theory applied truly to all the hydrocarbons it should 

 explain the facts, while most certainly it does not ; and the theory has 

 been a hindrance to the study. It is time that geologists ceased to 

 grope in the darkness of this inadequate theory. The volcanic theory 

 seems to fairly explain the essential facts, and it should be placed on 

 trial. The close association of hydrocarbon accumulations with volcanic 



