. FOREST OF WYRE AND TITTERSTONE CLEE HILL COAL FIELDS. 1007 



able coals; The Dowles Valley Measures were therefore believed to be an abnormally 

 thickened lower part of the Sulphur Coal Group, directly overlying the Old Eed 

 Sandstone. In an eastward direction also, as no workable coals were found in the 

 group of measures underlying the Sulphur Coals in the deep sinking at Shatterford, 

 it was concluded that there again the lower beds of the Sulphur Coal Group are 

 abnormally thickened, and rest directly on the pre-Carboniferous floor. If the Sweet 

 Coal Group had ever been deposited in the Dowles Valley and Shatterford regions, 

 the denudation of the Symon Fault had completely removed it before the Sulphur 

 Coal Group was formed. 



But, in 1895, Dr Kidston, on examining the plant-remains collected by myself 

 from the surface-beds in the Trimpley area, showed that there the lowest Coal 

 Measures directly overlying the Old Red Sandstone, instead of being of " Upper," 

 are of Middle Coal Measure age. Further, a number of plant-remains from ex- 

 posures at Cooper's Mill, in the Dowles Valley, on a horizon probably not more 

 than 200 or 300 feet below the Main Sulphur Coal of Button Oak and Kingswood, 

 also proved to be of Middle Coal Measure age. I was thus led to express the 

 opinion that the Sweet Coal Group is of Middle Coal Measure age, and corresponds 

 to the productive measures of Coalbrookdale and South Staffordshire, and that the 

 Sulphur Coal Group, with its pyritous coals and Spirorbis -limestone, is therefore of 

 "' Upper " Coal Measure age, i.e. equivalent to the barren measures that in South 

 Staffordshire lie between the top of the productive measures and the base of the 

 " Permian," and equivalent also to the Coal Measures of the Shrewsbury and Lebot- 

 wood Coal Fields. I stated also # that the " Upper " Coal Measures of the Wyre Forest 

 are " of great similarity to the upper parts of the Halesowen Sandstones of South 

 Staffordshire." As to the relationship between the two groups of measures in the 

 Wyre Forest district, I was at first disposed to accept the view that it is one of 

 strong unconformity, as seemed to have been proved to be the case in Coalbrookdale 

 by Marcus Scott and Mr Daniel Jones. But the discovery, based on the fossil 

 evidence, that in the Dowles Valley and around the Trimpley anticline the Middle 

 Coal Measures are not washed out, but are present in great thickness, led me 

 subsequently to doubt this conclusion, and to regard the abnormal distribution of 

 the two groups as due to overlap, accompanied perhaps by a slight unconformity. 

 It seemed to follow that the Sweet Coal Group of the Highley region, instead of 

 forming an isolated patch or outlier, restricted to the region lying north of the 

 Dowles Valley and west of Trimpley, extended into these districts in force ; and I 

 explained the absence of workable coals as due to the conditions having been un- 

 favourable to the formation of the requisite beds of vegetable matter on account of 

 the proximity of a land-mass to the south. In other words, the sweet coals worked 

 at Harcott and Highley, if followed underground southward and south-eastward, 



* " A Contribution to the Geology of the Wyre Forest Coalfield," 8vo, 1895, p. 19. See also " The Wyre Forest 

 Coalfield," Colliery Guardian, vol. lxxi, 1896, p. 351. 



TRANS. ROY. SOC. EDIN., VOL. LI, PART IV (NO. 27). 143 



