482 PARKFIELD COLLIERY. [Ch. XXIV\ 



Wolverhampton. Iii the space of about a quarter of an acre the 

 stumps of no less than seventy-three trees with their roots attached 

 appeared, as shown in the annexed plan (fig. 536), some of them more 



Fig. 536. 



Ground-plan of a fossil forest, Parkfield Colliery, near "Wolverhampton, 

 showing the position of 73 trees in a quarter of an acre.* 



than 8 feet in circumference. The trunks broken off close to the root, 

 were lying prostrate in every direction, often crossing each other. 

 One of them measured 15, another 30 feet in length, and others less. 

 They were invariably flattened to the thickness of one or two inches, 

 and converted into coal. Their roots formed part of a stratum of coal 

 10 inches thick, which rested on a layer of clay 2 inches thick, below 

 which was a second forest, resting on a 2-foot seam of coal. Five feet 

 below this again was a third forest with large stumps of Lepidodendra, 

 CalamiteSj and other trees. 



In the account given, in 1821, by M. Alex. Brongniart f of the coal- 

 mine of Treuil, at St. Etienne, near Lyons, he states that distinct 

 horizontal strata of micaceous sandstone are traversed by vertical 

 trunks of monocotyledonous vegetables, resembling bamboos or large 

 JEquiseta (fig. 537). Since the consolidation of the stone, there has 

 been here and there a sliding movement, which has broken the con- 

 tinuity of the stems, throwing the upper parts of them on one side, so 

 that they are often not continuous with the lower. 



From these appearances it was inferred that we have here the monu- 

 ments of a submerged forest. I formerly objected to this conclusion, 

 suggesting that, in that case, all the roots ought to have been found at 

 one and the same level, and not scattered irregularly through the mass. 

 I also imagined that the soil to which the roots were attached should 

 have been different from the sandstone in which the trunks are enclosed. 

 Having, however, seen calamites near Pictou, in Nova Scotia, buried 

 at various heights in sandstone and in similar erect attitudes, I have 



* Messrs. Becket and Ick, Proceed. Geol. Soc, vol. iv. p. 28?. 

 | Aimales des Mines, 1821. 



