3±& On the future Extension of the English Coal-fields. 



here thrown out, or whether we may expect to be able to 

 pursue it further westwards beneath this limestone*. 



I conceive it most probable that the Warwickshire coal- 

 field is separated from that of Ashby Wolds on the north by 

 a prolongation of the same anticlinal undulation which throws 

 up the transition chain of Atherstone and Nuneaton already 

 mentioned, although this prolongation is concealed by over- 

 lying horizontal strata of red marl. 



The Ashby coal-field, which skirts the Charnwood chain on 

 the north-west, appears to be subdivided into the two small 

 basins of Ashby Wolds and Cole Orton by an anticlinal 

 ranging in a direction parallel to that already assigned to the 

 Charnwood anticlinal, viz. north-west and south-east, and 

 passing through the town of Ashby: altogether the substrata 

 of this whole district appear affected by so many undulations 

 as to afford scarcely any indications of the probable lines in 

 which we may look for their prolongations, beyond their 

 known boundaries, beneath the horizontal investiture of red 

 marl. 



Crossing the Trent to the north, and approaching towards 

 the great emergence of the subjacent carboniferous lime of 

 Derbyshire, we find two localities in which coal is worked to 

 the south and south-east of Ashborne, viz. Darley Moor, and 

 Sprinxhall in Edlaston parish. Patches of carboniferous lime- 

 stone emerge from the red marl in the vicinity of both these 

 pits ; but we have as yet no information how far the circum- 

 stances indicate any connexion of the coal-measures between 

 them, or with the nearest coal-field on the west, that of 

 Cheadle, which must be within five miles of Darley Moor. 

 According to Farey, however, the undulation of the strata 

 constitutes the Cheadle field into a detached basin ; but the 

 whole of this district requires reexamination. 



Of the central coal-fields, that of Dudley remains for ex- 

 amination ; but the probable extension of this being connected 

 with the western coal-fields of Shropshire, it will be more 

 properly considered in a future communication, which I hope 

 to prepare for the ensuing month. 



Your old Correspondent, 



W. D. CoNYBEARE. 



* I was originally inclined to believe, from the general dip of the War- 

 wickshire coal-field tc the west, and that of the south-eastern portion of the 

 Dudley coal-field to the east, that these two fields extended continuously be- 

 neath the intervening red marl ; but Mr.Yates's observations of the eastern 

 dip of the Annesley lias, and a westerly dip along the eastern extremity ot 

 the Dudley field, where aLo, near Walsall, the transition lime emerges, 

 render it more probable that they arc separated by an anticlinal line. 



