in the Forest of Dean Coal-field. 



217 



The angular fragments found scattered in the sandstone roof of the coal are 

 obliterated or imperfect casts of vegetable remains. They are of the same sort of 

 sandstone as that which surrounds them, but highly indurated, as is also the 

 adjoining part of the rock to some distance ; but they have not the ferruginous 

 appearance of the nodules, although they are equally as hard. 



It is reported that similar nodules are found in the sandstone rock between the 

 Coleford High Delf and the Trenchard coal, which lies about sixty yards below. 



The sandstone which forms the roof of the coal extends to the surface and varies 

 in thickness according to the undulations of the ground : at the part where the 

 cross-section of the Horse is given, it is about ninety-four yards in the thickest part. 



Fig. 2. 



Plan of the Horse Fault, with its collateral branches called Lows. (Scale 24 chains to an inch.) 



Some portions of the roof in the Horse and Lows consist of a sandstone breccia, 

 containing quartz pebbles similar to those which abound in the pudding-stone of 

 the forest, also fragments of coal, ironstone, and vegetable remains. The pudding- 

 stone of the Forest Basin lies between the carboniferous limestone and the old red 

 sandstone, and it crops out all around the basin, attaining a considerable elevation 

 in the adjoining hills, 



VOL. VI. SECOND SERIES. 2f 



