Remews — Petroleum and Oilfields. 125 



remarks, above quoted, at the utmost, imply no more, and we 

 are, by them, left in the position that we have taken up, — that 

 bituminous substances are derived from accumulations of previously 

 carbonized vegetable substances. If any such deposits are known, 

 or if there is a probability of such beds having existed, and having 

 been destroyed, in the neighbourhood of bitumen- or petroleum- 

 yielding districts, it surely is more in accordance with the rules 

 of inductive philosophy, and more safe in practical investigations, 

 to construct our hypotheses upon such known facts than upon the 

 possibility of these substances having been derived from the de- 

 composition of animal remains. Acknowledging fully the diffi- 

 culties of the subject, we wotild yet 



" rather bear the ills we have, 



Than fly to others that we know not of." 



With respect to bituminous shales, ot pyro-schists, in which the 

 Hydro-Carbons exist in such intimate connection with the earthy 

 constituents of the rock, as to require distillation to set them free, 

 it is easy to conceive that, when they first became impregnated with 

 bituminous vapours, or oils resulting from a natural distillation, 

 they were placed under such circumstances as favoured a chemical 

 action in the substances introduced into the matrix, resulting in 

 their solidification within its pores. Where no such chemical action 

 was set up, the association between a rock and the distilled products 

 it contained, was, as before assumed, of a purely hydrostatical nature. 



It may be said, at first sight, that both the given theories are equally 

 inadequate to assist the practical man : that, according to either, 

 bituminous substances may be found impregnating the earth any- 

 where, or in any formation. But a little reflection will show the 

 thinking G-eologist that if he makes himself thoroughly acquainted 

 with the structure of a district, and with its internal history, he will, 

 supposing the distillation theory be a correct one, have some means 

 of ascertaining the possibility, and even the probability, of free 

 Hydro-Carbons existing therein. Their presence, in the first place, 

 would depend upon the existence, at some time or another, of coal 

 or lignite, either in that region or in one adjoining ; and, secondly, 

 the hope of determining the actual position of reservoirs will depend 

 upon our power of comprehending the conditions of the subterranean 

 drainage at the time of the supposed distillation. The presence of 

 anthracite should, under this view, induce an examination of the 

 subterranean structure of the surrounding districts, as such an 

 examination might tell us whether there was a probability of the 

 lost Hydro-Cai'bons of the anthracite being stored up within acces- 

 sible reservoirs, or the contrary. 



Any practical results of the acceptance of the distillation hypo- 

 thesis, under the very difficult circumstances in which the enquiry is 

 placed, may seem remote ; but cases may arise where it would be 

 advisable for the practical man to remember that the hypothesis of 

 Bitumen, or Petroleum, having arisen in some instances from a 

 " special mineralization " of animal remains, is a doctrine by no 

 means generally accepted, and most certainly containing nothing in 

 it upon which to base either a scientific or commercial investigation. 

 — E.C.H.D. 



