Yol. 68.] IN THE ' PEEillAX ' ROCEiS OF HAMSTEAD. 649 



III. COMPAEISON AND CoERELATION OF THE HaMSTEAD ' PeEIHIAN ' 

 WITH THE EEST OF THE GENEEAL ' PeEXIAX ' SUCCESSION 

 BORDEEING THE SoUTH StAFFOEDSHIRB CoALFIELD. 



(1) Relations of the Hamstead-Quarry Series and the 

 Hamstead- Colliery Series to the Coal-bearing Strata below. 



The Permian rocks described above, cropping out in the area east 

 of the Hamstead Colliery-shaft, and constituting the Hamstead- 

 Quarry Series, may be summarized in descending order as follows: — 



Thickness in feet. 



7. The Tower-Hill Sandstone Sub-group— fine sandstone 



with some marl 22 



6. The Mauor-House Breccia and Sandstone Sub-group — 

 breccias usually subangular, interbedded with sand- 

 stones : 70 



5. The Old-Quarry Sandstone Sub-group — calcareous sand- 

 stone 20 



4. The Rock-Farm Conglomerate Sub-group — calcareous 



conglomerate and sandstone 5 



3. The ]S^ew-Quarry Marl Sub-group — fine-grained sand- 



stones anfl marls 



On 



2. The Gravel-pit Sandstone and Conglomerate Sub-group — 



calcareous sandstone and conglomerate 40 



1. The Colliery-Sandstone Sub-group — soft sandstones and 



marls 20 



Total 202 



The surface-arrangement of these sub-groups is shown in the 

 map (fig. 1) on p. 644. 



The Hamstead-Quarry Series, as has been already pointed out, 

 follows immediately upon the strata pierced in the Hamstead 

 Colliery-shaft. This shaft - section has already been broadly 

 described by Messrs. F. G. Meachem & H. Insley,^ and in greater 

 detail by l3r. E. Kidston, Mr. F. G. Meachem," and Mr. T. C. 

 Can trill. 



I have to thank the owners of the Colliery for according me the 

 privilege of personally studying the detailed section of the strata 

 sunk through in the Hamstead shaft. This section, drawn to a 

 large scale, is kept at the colliery, and fig. 4 (p. 652) is a careful 

 reproduction of it, from the surface down to a depth of 1024 feet, 

 that is, 845 feet above the Thick Coal-seam. The section is here 

 published with the permission of the Manager of the Colliery 



1 ' Notes on the Rocks between the Thick Coal & the Trias North of 

 Birmingham & the Old South StaflPordshire Coalfield ' Kep. Brit. Assoc. 

 (Birmingham, 1886) 1887, p. 626. 



- 'The Search for Coal over the Eastern Boundary- fault of the South 

 Staffordshire Coalfield, with especial reference to the Sinking at Hamstead 

 Colliery & the Woi'king of the Thick Coal-Seam' Trans. Fed. Inst. ^iiu. Eng. 

 vol. vii"i (1894-95) p. 401. 



