GEOLOGICAL SOCIETY 



OF TENNSYLVANIA. 



295 



ANALYSIS OF SOME OF THE COAL FROM THE RICHMOND 

 MINES. By T. G. Clemson, formerly of the Royal School of Mines of 

 Paris, &c. &c. 



Upon the coal field of Richmond, lately visited by my 

 friend Mr Taylor and myself;, I have no observations to 

 make that could give additional interest to the very able 

 paper read by that gentleman at a preceding meeting of 

 this Society. 



The superior quality of this combustible, its unique 

 and singular position upon the granite, and the nature of 

 the superincumbent measures, make every thing re- 

 specting this singularly interesting coal field v^orthy of 

 record. The particular age of this formation is only to 

 be ascertained by reference to the contained organic re- 

 mains. The coal, as has been observed, lies upon granite, 

 som.etimes separated but by a few inches, at other times 

 in close contact with this rock. The singular appearance 

 and composition of the overlying strata, not apparently 

 deposited slowly, for some of these are of a porphyritic 

 nature, and dilFer from the measures that overlie the 

 coal in other parts of the world. More recent incum- 

 bent beds are also wanting, from which, had they exist- 

 ed, we might have deduced something more satisfactory 

 with regard to the age of the Richmond coal field. 



We have the honour to subjoin the composition of 

 three varieties of coal, taken from different pits sunk in 

 this basin. 



Coal from Willis's Pit, six miles north of the James 

 River. PL 16, fig. 2. 



This coal is jet black, has a shining pitchy lustre ; 

 powder, dark brown; breaks with an uneven fracture, 



