t 60s 3 



XXXII. Account of the Coal Formation at 



Durham. 



By Thomas Mackenzie, Esq* 



1 he district on which the city of Durham is si- 

 tuated, is composed of flcetz and alluvial rocks. 

 The alluvial substances are sand and coal ; and of 

 these the former is the most abundant. The flcetz 

 rocks belong to the series denominated by Werner 

 the Independent Coal Formation # , and which has 

 been considered as the oldest of the coal forma- 

 tions f . My investigations did not extend so far 



iRead igth November 1808.J 



Jameson's Mineralogy, vol. iii. p. 179. 



f It would appear from the Notes in Dr Anderson's 

 Translation of Von Buch's account of Landeck, that this 



