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On the Formation of Coal, 



Among the various subjects considered by geology, few are 

 of more general interest than the origin of those vast stores 

 of fossil fuel found in the coal fields of our own and other 

 countries. That this coal is nothing more than vegetable 

 matter, which has undergone a certain mineralising process, 

 is now generally admitted, and may be very readily proved 

 by placing some ashes from a fire under the microscope, when 

 the remains of tubes and fibres will generally be detected? 

 though of course the great mass of the vegetable structure 

 has perished during combustion. When we now consider 

 the thousands of square miles covered by beds of coal, measur- 

 ing many yards in thickness, and several times repeated, and 

 take into account the fact that, in the temperate zone, the 

 accumulated growth of a forest in a hundred years would not, 

 if converted into coal, cover the ground on which it stands 

 much above half an inch thick, we may well wonder how 

 such enormous masses of fossil fuel have ever been produced. 

 If a forest only forms some six or seventeenths of an inch thick 

 of coal in a century, when, it may well be asked, would it 

 form a bed of ten, twelve, or twenty feet in thickness, still 

 more the many beds piled up one above the other that are 

 seen in all the coal-fields round this city ? 



It is not surprising that this difficulty should have driven 

 geologists into many strange theories to account for the origin 

 of coal beds,^that some should have recourse to forests grow- 

 ing over vast continents, and swept by the Amazons or Mis- 

 sissippis of the antediluvian world into lakes or gulfs, where 

 the vegetable spoil was collected during long ages, and gra- 

 dually mineralised by various subterranean processes, — that 

 others should imagine some wholly unknown conditions of 

 climate, and atmosphere loaded with superabundant stores 

 of carbonic gas, and raised to more than tropical heat by its 

 proximity to the molten nucleus of the new-formed globe. 

 We shall not now discuss the merits of these or other theories, 

 thinking it will prove more acceptable to our readers should 

 we glean for their use a few of the more important facts con- 



