ON THE ORIGIN OF COAL. 



177 



erect on the seam of Coal there, seven feet in 

 thickness, some of them showing small portions 

 of their roots, whilst others rested with their 

 stems upon the Coal. These trees I measured 

 twenty-five feet upwards in the Blue bind, but 

 Mr. Ray, the intelligent engineer of colliery, had 

 traced one which went through the floor and into 

 the seam of the Albert Coal. A portion of this 

 stem, converted into Coal, is now in the museum 

 of the Manchester Geological Society. In the 

 strata near the bases of the stems occur plenty of 

 Pecopteris nervosa. 



Fig. 2. 



yds. ft. 



nr Coal Albert Mine 1 



4 Blue Bind and Shale (fossil trees) 19 



c Coal, Duchess of Lancaster 2 1 



d Floor, full of Stigmaria ^coirfes. 



Lately has been discovered in the floor of the 

 Victoria mine, Dukinfield, near Manchester, at the 



A a 



