54 Onthe Shell Marl and Coal regions of Virginia, §c: 
lame and my health feeble, and the road not only indifferent, 
but at a distance from the river’s bank ; and reflecting how far 
I was from home, in a country where no stage-coach could 
travel; I resolved, after a conflict of ten minutes, to turn 
about. This I most reluctantly did; and, after passing my 
inn, as well as the whole southern shore of the Crystal Lake, 
and casting many a look at the Giant’s Castle, with a deter- 
mination to atone for my existing neglect at some future pe- 
riod, I bade it adieu, and entered the wilderness, on my way 
to the valley of the Presumpsick. 
am, &c. 
S S. EDWARDS DWIGHT. 
PROF. SILLIMAN. - 
ARTICLE H}.—Practical remarks on the shell marl region 
of the eastern parts of Virginia and Maryland, and u 
the Bieadneas coal formation in Virginia and the odeitoa: 
ous region; extracted from a letter to the Editor, by 
JaMeEs PIERCE. 
In a recent examination of the eastern part of Virginia and 
, 1 have ascertained that rich shell marl, of marine 
Maryland, I 
~eggan:* 
Potomac from its mouth to within eight miles of the City of 
ashington, and in numerous places between the Potomac 
e Poa t t tt La * 
deposits of New-Jersey, and the marl beds of North-Caro- 
lina, deseribed by Professor Olmsted, in his valuable report 
