THE GEOLOGIST. 



JULY, 1858. 



THE IROKSTONE-FORMATIO:^^ OF THE FOREST OF DEAN; 

 WITH A SKETCH OF THE GENERAL GEOLOGY AND 

 INDUSTRIAL HISTORY OF THE DISTRICT. 



By Dk. J. J. W. WATsori, F.G.S. 



( Continued froin page 226. ) 



3I1LLSTONE Geit. 

 The coal-measures repoi-e conformably on a series of grit-beds, all 

 more or less charged with oxide of iron, and measuring together about 

 500 feet in thickness. In some places a bed of limestone intervenes 

 between the lowest bed and those above, but the general section, in 

 descending order, is as follows : — 



1. Coarse red grit-stone, called The Miner's Farewell Rock." 



2. Light red sandstone, with layers of variegated marls, which, 

 although partly indurated in the bed, fall to pieces by exposure to 

 the air. 



3. Fine-grained quartzose grit, much charged with iron in the middle 

 beds, constituting the Sandstone Mine Formation." In this group 

 there are two thin beds of coarse conglomerate, or pudding-stone. 



Coal Meastjejss. 



It would be impossible for me to enter into any adequate description of 

 this most important part of the Forest geology, without extending this 

 article to an undue length. The following summary, therefore, must 

 suffice, in the present instance j although I purpose describing the coal- 



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