70 
local, for a little further to the north the seam recovers 
pretty much its usual character. From this point up to the 
villages of Dodworth, Iligham, and Silkstone, the seam has 
been very largely worked, and found to be very uniform in 
general character, the tv^ o coals average 2 feet 6 inches to 2 
feet 7 inches, and the dirt parting never exceeds 9 inches. 
E to F, Fig. 1, Plate II. 
Between Silkstone and Cawthorne, however, the impor- 
tant change described in the introductory sketch sets in ; the 
main dirt increases in thickness, and other partings come in 
amongst the coal, splitting it up into a number of sub- 
divisions. 
The following two sections, in the neighbourhood of 
Cawthorne, will illustrate this change : — 
(1.) (2.) 
F. Fig. 1, Plate 11. G. Fig. 1, Plate II, 
Ft. In. Ft. In. 
Top coal ... Coal ... 14 1 10 
... Dirt ... 1 9 2 0 
... Coal ... 0 8 0 9 
Main Dirt ... Parting 22 8 2^J2 
^ Coal 1 5 
Uottom Coal ... Coal ... 19-^ Dirt 0 4 
^ Coal 0 5 
In both of these the thickness of the coals is below the 
average, and the old dirt parting has vastly increased in 
thickness ; but besides these changes, the top bed has become 
divided by a new band of dirt, and in the second section a 
similar change has affected the bottom bed, so that the seam 
has become broken up into four beds. There seems reason to ' 
believe that the gradual breaking up may continue to increase 
towards the north-west, till the seam, if it does not altogether 
cease to exist as a coal, becomes so continually divided and 
subdivided by the coming in of new dirt bands, that for all 
practical purposes it may be looked upon as non-existent. 
Whether, however, it actually comes over to this or not, the 
