MODE I. GRAPHITE. 



water is collected in them, at the bottom of 

 which, graphite is gathered every six months."* 



Our ingenious author is mistaken, when he 

 says the graphite of Cumberland is found be- 

 tween layers of a kind of slate, traversed by veins 

 of quartz. Several specimens of the rock are 

 now before me. 



1. Nodules of graphite in the rock itself; Graphite of 



Borrodale. 



which appears decomposed, and in some parts 

 tinged with oxyd of iron, arising from the par- 

 tial decomposition of the graphite. The stone 

 easily yields to the knife, and is of a bluish grey 

 colour mottled with white. It has an unctuous 

 steatitic appearance, and seems to be a decayed 

 serpentine. 



2. The same rock, at a further distance from 

 the mineral, and undecomposed. This seems a 

 Saussurite, or magnesian basaltin. It is of a 

 deep grey colour with dots of light brown, which 

 may be a decomposed felspar; and is mixed 

 with large patches, which approach the nature 

 of indurated steatite, of a light greenish grey, 

 mottled like the decomposed substance which 

 contains the nodules. It is, upon the whole, a 

 magnesian rock, of a particular description, 

 with a stong argillaceous smell, in this and other 



* Brongn. ii. 53. 



