1890 .] 
461 
[Shaler. 
probably exceeding 3500 feet. From this elevation the profile de- 
scends in the broad valley of the upper Tennessee to about a thou- 
sand feet above the sea level ; thence it again rises until in the 
mountains of North Carolina, we enter a field where many peaks 
rise to more than 6000 feet in height. From the front of the ice 
sheet near Cincinnati to the central part of the North Carolina 
mountain district is about 200 miles. It is to be observed that the 
whole of this district is within the same great valley and in a re- 
gion where the isotherms at the present time follow each other with 
normal curves. We may therefore fairly conclude that under the 
usual conditions of climate such as prevailed in North America, 
the ice line should be found in the mountains of North Carolina 
at the height of 2000 feet above the base of the glacier at Cincin- 
nati, or say at 3000 feet above the level of the sea. From that 
level to the top of the North Carolina mountains or say for the 
height of 3500 feet we should have indications of glacial conditions. 
A tolerably careful investigation of this country has shown me no 
evidence of ice action whatsoever and all the other students of the 
subject who have visited this area have failed to find any facts 
which might afford even a supposition of glacial work in that field. 
I am therefore compelled to assume that the slope of the snow line 
rose so rapidly from the ice front at Cincinnati southward that it 
passed above the summits of these mountains. 
If the elevation of western North Carolina was in the form of 
an isolated peak, we might have less confidence in this indication. 
But the district of land which should have lain much above the 
snow level is some thousand square miles in area, a field sufficiently 
great to have developed very extensive glacial areas in case the 
peaks lay above the line of perpetual snow. The same considera- 
tions, though in a less accented way, are met when we examine the 
highlands of the Blue Ridge in Virginia or the Alleghany moun- 
tain district on the uplands of Virginia and West Virginia. A 
large part of the Blue Ridge in Virginia is high enough to have 
been the seat of glaciers, provided the snow line were anywhere near 
the level of the glacial sheet where it crossed the existing Atlantic 
coast. The traces of glacial work in the Blue Ridge are extremely 
scanty. At the western extremity of Rock Fish Gap, immediately 
south of the Chesapeake and Ohio Railway, near its junction with 
the Shenandoah Valley Railwa}', there are accumulations which 
apparently are to be classed as glacial. This point is about 1 600 
