462 



Resting on the Millstone grit, then, we have the under division, 

 comprising the Vobster and New Rock groups of veins. Beginning 

 at Mells this division extends through Vobster, Coleford, Edford, 

 Nettlebridge, and Slacker's Hill, to Old Down and Emborrow. 

 From this point its probable course is by way of Chew Down, Litton, 

 Cawley, East Harptree, West Harptree, Compton Martin, and 

 Ubley, to Nempnet. Here a narrow neck of the under division 

 probably passes down the valley between Broadfield Down and the 

 Mendips into the Nailsea basin. 



The margin of the division in the principal basin, however, 

 extends northward from Nempnet by Ridge Hill, Upper Littleton, 

 Barrow House, Long Ashton, Bristol, Horfield, Filton, and Little 

 Stoke to Cromhall, in the extreme north of the basin. To define 

 its eastern margin we must take a line from Yate by Wapley, 

 Abstone, Wick Court, Beech, Twertou, Odd Down, Southstoke, 

 Lower Twinhoe, Norton St. Philips, and Buckland Dinham, tp 

 Mells, the point from which we set out. 



We have thus traced as by a ring fence the outline of the 

 principal field. In the Nailsea basin the under division probably 

 extends from Clevedon by way of Tickenham, Nailsea Heath, 

 Backwell Common, West Town, Brockley, Yatton, Churchill, and 

 Banwell, on towards the Channel, but in that direction there are 

 few facts to guide us. 



The Pennant sandstones come next in ascending order, and it is 

 desirable that their range should as far as practicable be defined, 

 because they form the great separation beds between the upper and 

 lower division of productive Coal measures, and further, that mining 

 adventurers may be deterred from embarking their capital in 

 barren ground of enormous thickness, beneath which the under 

 division for the most part lies at too great a depth to be 

 profitably worked. The Pennant lies in three separate districts. 

 Taking the more extensive first — its outcrops probably extend from 

 Babington by Holcombe, Stratton-on-the-Fosse, Chilcompton, and 

 Stone Easton, to Cameley and Temple Cloud. Between Temple 

 Cloud and Coal-pit Lane its course is uncertain. In the opinion of 

 some it passes round by Hinton Blewefc to the west of Bishop 

 Sutton and thence to Coal-pit Lane, in which case the veins at 



