Vol. 6^.^ BASEMENT-BEDS OF THE BRISTOL COALFIELD. 449 



at 211 yards, the Ashton 'Top Vein' at 295 yards, the Ashton 

 4 Great Vein ' at 310 yards, and the ' Little Vein ' at 359 yards. 



The succession at the Starveall pit, about three-quarters of a 

 mile distant, was also given by Anstie (loc.jam cit.) as follows : — 



' XVIII, XIX. Bedminster ' Top ' Seam (3 ft. 3 in.) at 58 yards. 



XX. Bedminster 'Great' Seam (3ft. 8 in.) at 98 „ 



XXII. Bedminster ' Little ' Seam (1 ft. 6 in.) at 126 „ 



Coal at 240 „ 



XXIII. Smith's Coal at 296 „ 



XXV. Ashton ' Top ' Seam (2 ft. 6 in.) at 310 „ 



XXVI. Ashton ' Great ' Seam (5 ft. 8 in.) at 334 „ 



Ashton ' Little ' Seam (2 ft. 4 in.) at 368 „ ' 



This account was stated not to be so accurate as that of the 

 Ashton Shaft. 



A generalized section of the beds passed through in the ex- 

 ploration-branch is as follows : — 



Thickness in feet inches. 

 ' Bed Ash ' or ' Little Vein.' 



Strata 20 8£ 



Coal b 



Strata 38 9| 



Coal 1 



Strata 24 6 



' Gray's Vein ' 1 8 



Strata 44 10 



' Smith's Coal ' 1 



Strata 183 U 



BastardCoal 6^ 



Strata 15 6£ 



Millstone Grit 130 4^ 



A more detailed description of the beds passed through, based 

 upon actual examination of material taken from each bed and 

 examined at the surface, is appended (see § IV, p. 453). 



The first evidence of fossiliferous shale was obtained on the spoil- 

 heap of the colliery, the shale being afterwards localized at a depth 

 of 84 feet below the ' Gay's Vein/ 



Immediately above and below the 12-inch coal lying over the 

 ' Gay's Vein ' occur two beds of black micaceous shale, 4 inches 

 and 21 1 inches thick respectively, in which Lingula mytiloicles is 

 abundant. The ' shell-bed,' as it came to be called by the miners, 

 has a thickness of 20 feet, and was found to be abundantly 

 fossiliferous throughout. It is a soft black shale, very evenly- 

 bedded, indeed very often laminated, with (in places) small nodules 

 of ironstone and bands of the same material, one of the latter being 

 4 inches thick. The resemblance of some of the ironstone-nodules 

 to the ' bawn-pots ' seen in the Lancashire Lower Coal-Measures 

 is most marked. As in the ' bawn-pots,' goniatites were found 

 projecting from the surface, while the interior contained iron- 

 pyrites. Occasionally the shale became greyer in colour and 

 micaceous, and fractured irregularly. Towards the upper part 

 were found a few well waterworn quartzite-pebbles, very similar in 

 size and appearance to those occurring in the conglomerate-grits. 



2e:2 



