CONSISTENCY OF GEOLOGY WITH SACRED HISTORY. 403 



base and thirty six feet long, lying nearly horizontally between the 

 strata of sandstone. Its composition was carbonate of lime 60, oxide 

 of iron 18, carbon 9, aliimine 10. 



Another fossil tree has been recently discovered in the quarry of 

 Craigleith, near Edinburgh, whose geological position is in the moun- 

 tain limestone, and considerably below the great coal basin of the Lo- 

 thians. Its elevation is seventy five feet above the level of the sea, 

 and its roots were in the bottom of the quarry. The length of the 

 stem was forty seven feet — a large branchless trunk — in some parts 

 much flattened, so as to afford an elliptical section. At the largest 

 place, its diameter was five feet by tvv^o, and at the smallest, nineteen 

 inches by sixteen. Its branches, and many feet of its top, are gone ; 

 it was probably sixty feet long, and the incumbent mass of sandstone 

 appears to have been one hundred feet thick ; the bark is converted 

 into coal. The composition of this tree is, carbonate of lime 62, 

 carbonate of iron 33, carbon 5, with the sp. gr. 2.87. It was a conifera. 



In the great coal-field of the North, in Britain, fossil plants are usu- 

 ally found lying parallel to the strata, but much broken and compress- 

 ed, and their parts scattered ; but some vigorous plants, generally Si- 

 gillarise, appear to have been so strong as to resist the torrents and 

 to remain in their natural position. 



It results from Mr. Witham's discoveries, that plants with their or- 

 gans of fructification apparent, (gymnospermous phanerogamic,) are 

 much more frequent in the coal formations than has been imagined, 

 and that proper trees, of true ligneous fibre and of great size, existed 

 even earlier than the bituminous coal.* 



More recent fossil trees and plants. 



Among the more recent secondary rocks, vegetables increase in 

 quantity and variety, as we approach the tertiary, in which we find in- 

 humed wood in the form of lignite, or bituminized wood, or wood 

 slightly mineralized ; eventually we find wood unchanged ; and thus 

 we trace the vegetable families, from their commencement on the 

 borders of the primitive, quite down to our own times. In the loose 

 sand, gravel, and detritus, we often find trees, at every depth, be- 

 tween the surface of the ground and the fixed rocks below ; the sur- 

 face is often covered by bowlders of travelled stones, and the deposi- 

 tion is evidently diluvial. 



* Am. Jour. Vol. XXV, p. 109, 



