BITUMIA'OUS AND ANTHRACITIC. 461 



inches thick, and in the same place with their roots. The largest 

 of these was five feet in diameter,v at the base, and eleven feet 

 high. He conceives it probable, that they grew vx^herc they occur.* 

 In a subsequent paper, read February 26, 1840, Mr. Hawkshaw, 

 after mentioning the discovery of another fossil tree, standing on 

 the same coal-seam, makes this observation : " If the coal be con- 

 sidered as the debris of a forest, it is difficult to account for not find- 

 ing more trunks of trees than have been discovered in our coal- 

 basins, and it is only, perhaps, by allow^ing the original of om* coal- 

 seams to have been a combination of vegetable matter, analogous 

 to peat, that the difficulty can be solved."f 



After Ml*. Hawkshaw's ffi'st communication, Mr. Beaumont, 

 in a paper read to the same Society, November 6th, 1839, upon 

 the subject of the same trees, states several objections to the drift 

 theory of coal, and conceives, that the vegetation grew where it 

 is found. Upon comparing these objections with my own, as 

 given in the foregoing pages, I find that they all rest upon a dif- 

 ferent class of facts, and are wholly distinct in their bearings. 

 Mr. Beaumont states, that the vegetation which formed the coal 

 grew on swampy islands, that it consisted oi ferns, calamites, coni- 

 ferous trees, Sec, which operated, through their decay and regenera- 

 tion, to form peat bogs ; and that the islands, by subsiding, were 

 covered with drifted sand, clay, and shells, till they again became 

 dry land, and supported another vegetation ; and this process, he 

 supposes, was repeated as often as there are coal-seams.^ 



Dr. Buckland, in commenting on this hypothesis, observes, 

 that, " in denying altogether the presence of drifted plants, the 

 opinion of the author seems erroneous ; universal negative prop- 

 ositions are in all cases dangerous, and more especially so in 

 geology. That some of the trees, which are found erect in the 

 coal-formation, have not been drifted, is, I think, established on 

 sufficient evidence ; but there is equal evidence to show, that other 

 trees and leaves innumerable, which pervade the strata that 



* Hawkshaw, in Proceedings Geological Society, London, No. 64 

 t Hawkshaw, in Proceedings Geological Society, London, No. 69. 

 t Beaifmont, in Proceedings of Geological Society, London, No 65. 



