South-western Coal District of England. 263 



will be perceived that in most of their attending circumstances these faults are 

 analogous to the flukans of Cornwall. 



The number of collieries in work formerly was probably greater than it is at 

 present^ though the total produce of the mines is certainly much greater now 

 than at any former period. The traces of ancient workings are to be found 

 over many whole parishes^ in which not a single pit is now in use. Thus 

 the whole line of collieries at Brislington^ Queen's Charlton, and Burnet, has 

 for many years been abandoned, as are most of those in Pensford andtretween 

 Pensford and Marksbury. Most of the Kingswood pits are also deserted. 

 The enlarged scale and spirit with which those mines are worked that are 

 now in activity much more than compensate for the diminution in num- 

 bers. 



The seams of coal are very thin* in comparison of those which are worked 

 in the principal English coal-fields, and in most of such would be passed over 

 as unworthy of notice. The aggregate thickness of the seams worked in any 

 single coal-pit scarcely exceeds that of one of the ordinary seams in the princi- 

 pal districts ; and the total of all the beds in the mining-field would be little 

 more than double of the largest m.ain of Staffordshire. That seams so thin 

 should be sought for through lias and oolite, at the enormous depth of 200 

 fathoms, as on Clandown, must excite surprise in those acquainted only with 

 other coal districts ; and that, under these circumstances, the seams should 

 be worked with profit, must be attributed chiefly to the highly improved ma- 

 chinery introduced into this district, the result of which is, that the quantity of 

 coal delivered at the mouth of one of these pits in a single day averages at 

 from 60 to 100 tons. 



The district may be considered as able to answer largely the future demand; 

 for, 1st, most of the ancient pits now abandoned might be drained, and worked 

 to advantage on the present improved system ; 2dly, much of the area is still 

 untouched, as will at once be seen on referring to the collieries indicated on 

 the Map. It will especially be seen that in the south-western angle of the basin 

 there are no coal-pits worked to the westof Bishop's Sutton, though there is every 

 reason to believe that the coal-measures are continued beneath the valley of 

 Wrington between the Mendips and Broadfield Down. We have already 

 noticed the point near Winford where the millstone grit rests against the lime- 

 stone of Broadfield Down, and have stated it as probable that the lower coal- 



* Where the coal-measures, however, are much deranged, as is the case with the lowest of those 

 in the Nettlebridge district, a seam will often suddenly swell to 4 or 5 times its usual bulk, and as 

 suddenly contract, so as nearly to vanish. 



VOL. VI. 2 M 



