436 MR. H. KAY ON THE HALESOWEN SANDSTONE [Oct. I913,. 



Jukes does not appear to be used locally, the beds being known 

 as the Old-Hill Marls, or as the Oldbury Marls, from the 

 districts where they are typically developed. For the Keele Series 

 110 local name seems to have been proposed. 



The detailed work of Prof. Lapworth in the ' Spirorbis-IAmestone 

 Group,' as also that of Mr. W. Wickham King in the Permian 

 strata, is of the highest importance. "Unfortunately, no such 

 detailed work has been carried out in regard to the Halesowen 

 Sandstones and the Old-Hill Marls, and the boundary between them 

 has never been denned. The only further reference to these rocks 

 that I have been able to trace, is contained in a brief abstract of 

 a paper by Mr. King, ' On the Conglomerates of the Halesowen 

 Sandstones,' read before the Birmingham Philosophical Society some 

 twenty years ago. 



III. The Eed Coal-Meastjre Clays or Old-Hill Marls. 



These beds are essentially argillaceous and of a dull-red or purple 

 colour, with characteristic bands of green grit. The clays are rich 

 in iron, often containing from 15 to 20 per cent. l They form the 

 raw material of the celebrated ' Staffordshire blue bricks.' Some 

 varieties, less ferruginous, are used in the production of terra-cotta 

 for architectural work. 



In the northern portion of the coalfield, a thin coal is found nearly 

 midway between the base and tbe summit of the series. 2 At 

 Ireland Green, near West Bromwich, this coal appears to be 

 represented by some 18 inches of black bituminous shale, in which 

 plant-remains are abundant and well preserved. At Old Hill, 

 greenish-grey carbonaceous shales with coaly partings are found 

 on or near the same level. Here also the plant-remains occur in 

 great abundance. 



The green grits are found both above and below this horizon, 

 and often pass gradually into coarse ashy, greenish or brownish 

 sandstones, which form the well-known ' Espley Bock ' of the 

 miner. In the southern portion of the coalfield, the upper ' Espley 

 Eock ' further develops into more or less massive conglomerates,- 

 particularly south and west of Old Hill. Some of the pebbles are 



' large angular fragments of Lickey quartzite, the nearest outcrop of which is 

 6 miles south-south-east of Old Hill.' 3 



Others are of fossiliferous Llandovery sandstone, but very many 



' consist of fragments of trap, not, however, of basalt or greenstone, but of 

 brown and purple porphyry (or felstone) very like some of those so abundant 

 in the Permian rocks of the Clent Hills.' 4 



i Wood & Ivery, 'Bricks & Brickmaking' Birmingham, 1878. 



2 'Summary of Progress of the Geological Survey for 1910' Mem. Geol. 

 Surv. 1911, p. 14. 



3 W. Gibson, 'On the Character of the Upper Coal-Measures of North 

 Staffordshire, Denbighshire, &c.' Q. J. G. S. vol. lvii (1901) p. 262. 



4 J. B. Jukes, 'The S. Staffs. Coalfield' Mem. Geol. Surv. 2nd ed. (1859) p. 29. 



