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ON THE COAL MEASUEES AT THE GLEE HILLS. 

 By Me. Geo. H. Piper, F.G.S. (President). 



No doubt most of my hearers are familiar with the generalized statement that 

 coal lies in the lap of the Mountain, or Carboniferous, Limestone. This rock is a 

 tough, bluish-grey, crystalline formation, and occurs in massive beds immediately 

 upon a band of yellow sandstone, deposited upon the l>evonian Limestones and 

 Old Red Sandstones, which prevail so extensively in Herefordshire. At the Glee 

 hills the Mountain Limestone is found only in two places, one on the south and 

 the other on the north of the Titterstone Glee. These beds are in some places 

 highly fossiliferous, and are exposed, north-eastward of the Glee hill, at Oreton 

 and Farlow. The quarries at Oreton supplied the very numerous and fine speci- 

 mens of palatal teeth of Orodus ramosus, and fish spines, in the collection of the 

 late Mr. Weaver Jones, of Cleobury, which many of us have seen ; and here we 

 have the base of the Glee hill Goal Measures. The limestone occurs again bet- 

 ween Gornbrook and Knowl, southward of the hills. From the nearly vertical 

 positions of the sections at this jjlace it has been suggested that the great disloca- 

 tion of the Mountain Limestone, which is traceable in various parts of the Glee hill 

 district, occurred before the carboniferous deposition. The condition of the rocks 

 proves that before the coalfields were laid down, subterranean forces were active 

 beneath this tract, but the present position of the lava affords satisfactory evi- 

 dence that it was poured out by volcanic Tneans over the surface of the coalfield 

 after the carboniferovis deposit had taken place. Further proofs of earthquake 

 forces having existed here, before the deposition of coal, may be found at Oreton 

 and Knowbury, where there is evidence of great dislocation of the Mountain 

 Limestone, which must certainly have occurred before the Millstone Grit was 

 deposited. The Rev. W. S. Symonds says, "Nothing in physical geology appears 

 to me to have less foundation than the supposition that such outliers as the Glee 

 hill Limestone and those of North Wales, were little isolated coral reefs. The 

 Millstone Grit which overlies them should be sufficient to overthrow .such theories, 

 for, even .allowing that isolated coral reefs may have accumulated in the Lower 

 Carboniferous seas, we cannot suppose that the Millstone Grit could have been 

 deposited above every outlier by accommodating and peculiar currents, which 

 spread their particular and peculiar pebliles over those accommodating coral is- 

 lands, and adapted their flow to such widely distant and separated areas as are 

 those of the Little Orme district, near Llandudno, the Titterstone Glee, and Pen 

 Gerrig, near Grickhowell. Fossil shells and fish spines — Ctenacanthus — similar to 

 those found at Oreton, occur at Knowbury. Producti have been obtained at 

 Gorstley Rough ; thus the fossils yielded by these patches of limestone are iden- 

 tical with those found in carboniferous limestone districts miles and miles away, 

 on the flanks of Dean Forest in the South Wales Coalfield, or the isolated outlier 

 of Pen Cerrig." The inference to be drawn from these appearances is, that at 



