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millstone grits : while on the other line there are only six 
beds worked, viz. Shafton, Mapplewell, thick coal, Flockton, 
Park Gate, and Silkstone, and some of these very imper- 
fectly developed ; the three beds which Mr. Morton describes as 
being valuable and important here are severally, the Flockton, 
2.0. ; the Lower Flockton, the best in Yorkshire, 6 inches to 
10 inches, the Park Gate, 4 feet 9 inches, and the Silkstone, 
2 feet. Surely the Lancashire gentlemen would exclaim 
upon an inspection of the completed section, that we must have 
made some mistake ! — that while they had 50 worked beds, 
amounting to 150 feet of sohd coal, we had only six diminu- 
tive, forsooth riding coals, amounting to 24 feet ; they would 
say that their great coal field can certainly have no relation- 
ship with the Yorkshire, at least if it has, the Yorkshire is 
only the fag end of it ! ! 
The rocks of our Coal Field on the Don line are also well 
developed, particularly that of Hooton Roberts, from which 
place it was carried to build Wentworth House, the red 
rock in Canklow Wood, and the Bradgate rock at Sheffield. 
The Millstone grits are as well exhibited, and particularly the 
lower one on Ladyborough, better than at Saltersbrooke. 
The Limestone shale has also its peculiar interest, abounding 
in marine fossil shells : a vertical section in Derbyshire com- 
pared with another through the same stratum in the north of 
Yorkshire, would of itself be a sufficient refutation of the 
opinion that coal grew upon the spot where it is now found. 
Volcanic rocks are found in most Coal Fields, those belong- 
ing to our own are not found north of Tidswell. The number 
of these beds, whether there are three, as maintained by Mr. 
Hall, or only one, as by Mr. Hopkins — their connection with 
and intersection by metalliferous veins, — the direction of the 
veins themselves, — their products, a comparison of them with 
those found in the north of Yorkshire, — the crystallized mate- 
rials embedded with the ores, — the stratum in which each vein 
is most productive, — are all subjects worthy of consideration. 
