ELISHA MITCHELL SCIENTIFIC SOCIETY 102 
edges of the slates, which vary in hardness and obduracy 
from point to point, the harder sheets projecting upward 
as ledges, and the intervening softer sheets being wash- 
ed out as depressions, which thus give rise to the shoals 
and rapids. 
ON THE YADKIN RIVER. 
The Yadkin river strikes the slate belt some 12 or 15 
miles below the Southern railroad crossing near Salis- 
bury, and fora distance of 20 miles below this point the 
geologic conditions in this slate have resulted in a suc- 
cession of shoals and rapids which promise to be of great 
value in connection with the development of manufact- 
uring enterprises. 
Where the Yadkin river crosses the larger of these 
belts of slates and schists there is a greater concentra- 
tion of the hard and soft material, and consequently a 
greater concentration of fall in the river at certain points, 
than is described above as occurring on Haw and Deep 
rivers; yet on the whole this Yadkin river section, illus- 
trated with approximate accuracy in fig. 3, may be con- 
sidered as fairly typical for sections of country where 
these belts of rock exist. The space between 1 and 2 in 
the diagram represents the ‘‘narrows”’ section, a distance 
of nearly 5 miles. The rock is eruptive in character, 
though an obscurely bedded conglomerate at the upper 
(N.W.) side. It is all hard, but not uniformly so, being 
harder and more obdurate at certain places, arranged at 
intervals, producing the narrows rapids at the upper end 
(just below 1) and the ‘‘little falls” and ‘‘big falls”? near 
the lower end (just above 2). The total fall from 1 to 2 
is nearly 100 feet. 
