122 Reviews — Petroleum and Oilfields, 



knowledge that these have or have not been found in such or such a 

 locality. Stratification aids him ; Carboniferous Eocks indicate a 

 great probability, the presence of Oolites a possibility, of Goal ; 

 whilst Tertiary beds may contain a more or less valuable substitute. 

 But Bitumen and Naphtha and Petroleum set all calculations 

 hitherto made at defiance. They may be bored into in a Palgeozoic 

 region, far below any coal-bearing rocks, or they well up through 

 Tertiary strata; Shales may be impregnated with them in the 

 Silurian, the Devonian, or the Oolite Formations ; the mineral 

 oil may exude slowly and cold from the cells of a most ancient 

 coral, or boil up, and cooling form a recent rock. So multitudinous 

 are the modes of its occurrence — so baffling, at first sight, are its 

 associations with rocks of all ages and all kinds ; so concealed are 

 its hidden sources, if apparently of recent origin, or so iitterly lost, if 

 of ancient date, — that it is scarcely a wonder that geologists have 

 allowed it to remain a known but an unexplained existence ; that, at 

 the best, but hazy ideas of the truth have been thrown out, amongst 

 a host of most unnatural theories. For sundry examples of the 

 latter we must refer the reader to Mr. "White's little work ;^ though, 

 we regret to add, that the theory which that author suggests to 

 replace them is by no means more scientific or even comprehensible. 

 Chemical Agency is a very safe expression ; but the assumed exist- 

 ence of " Jdppuric acid," of " almonds, or other Benzoic acidulous 

 food," and of the constituents of mammilliary (sic), and other 

 remains of sedimentary organism in Palgeozoic Strata, would be 

 simply laughable, if it did not appear to be scientific (1) quacTcery. 

 The only object of the whole farrago of nonsense appears to be to 

 make people believe that oil-wells in general, and Canadian ones in 

 particular, are inexhaustible — a view that is contrary to the opinion 

 of those who have disinterestedly studied the statistics of the 

 American oil-fields.- 



Two theories have met with more favour than others, and of 

 these two, it appears to us that the least tenable has obtained the 

 most and best supporters. A theory, which, to account for the 

 presence of Petroleum in Silurian or Devonian strata of undoubtedly 

 marine origin, assumes that the remains, not merely of sea-weeds 

 but even of molluscous animals, may be converted into bitumen 

 similar to that derived from the mineralization of the higher plants, 

 " must give us pause," though it be supported bj^ the names of 

 Dana and Logan. The best evidence adduced in favour of the 

 view that fluid bitumen is the result of a " special mineralization," 

 of even vegetable remains, that of Mr. Wall, in his remarks on the 

 Geology of the Island of Trinidad, appears to us to be defective ; for 

 though that writer implies that the beds of vegetable matter under- 

 going conversion by chemical reactions, at the ordinary temperature, 

 and under the normal conditions of climate, become a solid bitumen 

 identical with the fluid of the " pitch-lake," yet, we fail, on referring 

 to the original paper, to see the connection between the one and the 



^ Oilfields of Canada, etc., p. 62. 



- Vide Logan, Geological Survey of Canada, 



