REVIEWS IOI 
immediate connection with the coal, while marine shells are found in 
the sediments separating the beds. 
The seams contain true coal and “‘ pitch coal.”’ The true coal is of 
good quality, containing little ash. Much of it is “fat,” containing as 
high as 66 per cent. of volatile matter. The ‘ pitch coal” is found in 
veins and irregular masses in or near the true coal. The latter part of 
the paper is devoted to a discussion of the “ pitch coal” by William C. 
Day, who concludes that it is an asphalt, as it shows none of the char- 
acteristics of coal. 
Whe 40, Jb, 
