288 GEOLOGY. 
black, and the masses break with a conchoidal fracture. After long exposure to the air, 
especially in a dry situation, the mass contracts so much that it becomes traversed by numerous 
fissures, and may then be broken up by the hand. The powder and streak are dark-brown, 
in which respect the mass corresponds with lignites or brown coal; but when ignited it burns 
freely with black smoke and a bituminous odor. It contains a large per centage of bituminous 
or volatile matter; so much, that it burns with a brilliant flame. It does not leave a large 
quantity of ash, and these good qualities render it valuble as a fuel. 
-Not having visited the locality, I cannot describe its geological position and association, nor 
present any observations upon the extent and thickness of the beds, and their prospective 
importance and value as a source of fuel. I was, however, informed by the gentlemen who 
called my attention to the coal that it existed in beds about three feet thick, and that it was 
overlaid by strata of sandstone. 
