GEOLOGY 



rock has weathered away leaving the hardened parts outstanding. The 

 top of Bramcote Hill is filled with porphyritic white crystals of baryta 

 enclosing the sand grains in its substance, and these weather out into 

 pebble-like lumps, but there is no special conglomerate only the 

 ordinary pebbles found in other parts of the hill. The cap of the 

 Hemlock Stone is impregnated, but the base is less so, if at all. The 

 top is aiso pebbly and the lower part soft and false-bedded without 

 pebbles. For these reasons the upper part more easily resists the weather 

 and therefore overhangs. In the neighbouring Stapleford Hill the lower 

 part is in places fully charged with baryta crystals side by side with 

 parts which are uncharged and soft ; at the same time the pebbly and 

 non-pebbly parts are here found somewhat alternating. At the bottom 

 of Bramcote village the sandstone has a peculiar mammillated structure, as 

 though the grains were agglutinated by an infiltered mineral. Now the 

 presence of baryta and its results in this case were first made known in 

 1885, but in 1882 Mr. Strahan, in his Survey Memoir, 'On the country 

 round Chester,' had already described rocks on the summit of Beeston 

 Castle with abundance of baryta, showing also the porphyritic crystals, 

 the massive form with glistening faces, and the mammillated, agglutinated 

 sandstone, just as if he had been describing Bramcote and Stapleford 

 Hills. They are also false bedded and red in parts, and in parts pebbly 

 and yellow. Lithologically, therefore, and chemically the two sets of 

 deposit agree. There remains only the question of position. At Beeston 

 Castle these beds overlie the Upper Red Sandstone ; at Stapleford Hill 

 they reach a height of 33 i feet above O.D., and at Bramcote Hill of over 

 300 feet, while a section of ordinary Pebble Beds is seen in Moor Lane, 

 only 460 yards distant from the latter, at a little over 200 feet. They are 

 therefore more likely to represent the Upper Red Sandstone and higher 

 beds than the Lower Red Sandstone and Pebble Beds ; especially as the 

 junction of the two latter is seen at Catstone Hill, if miles to the north 

 on the other side of an upthrow fault of large amount at nearly the same 

 level, but differing in the character of both components. 



There is every reason, therefore, to believe that the rocks of the 

 Hemlock Stone and neighbouring hills are the equivalents in a diminished 

 form of those that overlie the Pebble Beds at Beeston Castle, especially 

 as similar phenomena are observable in the interval. These have been 

 divided in Cheshire l into two parts : a lower, softer part, called the 

 Upper Red Sandstone, and an upper, harder part, called Keuper Basement 

 Beds. It appears, however, that the only grounds for placing the 

 upper division in the Keuper are an apparent gradual passage upwards 

 into the Waterstones, and an apparent unconformity with the lower 

 division, below a well marked conglomerate both of which grounds 

 are contested by Mr. Strahan and which are certainly not applicable at 

 Bramcote and Stapleford Hills. Here at all events no beds have any re- 

 lation to the Keuper, but all are the topmost beds of the Bunter whether 



1 Strahan, loc. cit. See also Hull, 'Triassic and Permian Rocks,' Geol. Surv. Mem. p. 9, and Strahan, 

 Geol. Mag. 1881, p. 401. 



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