348 The American Geologist. June, isqi 
teau, and caused its marked elevation above the surrounding 
districts. 
Special attention is directed to the following sentences ( in 
which the italics do not belong to the original ), since they give the 
author's views as to the emergence of this area from the sea. 
1 ' In the region with which we are specialty concerned, the line of 
the Unaka Range and Blue Mountains, which was perhaps never 
altogether submerged, was upraised gradually into high land. The 
Cambrian and Silurian strata were subjected to erosion; and 
streams carrying the materials flowed down the flanks of the emer- 
gent land into the sea or estuary to the westward. As time went 
on, these western tracts, wherever in the line of anticlines, were 
themselves elevated and eroded, and ultimately the S3*nclines 
themselves. " The author evidently conceives the existence of the 
sea in the synclinal region along the Cumberland plateau, after 
the anticlinal area to the westward had ahead} 7 been elevated 
above the sea. This, however, is not consistent with the main 
tenor of his paper, of which the following paragraph is a brief digest. 
That the Cumberland plateau formerly occupied a relatively 
lower position than the areas towards the eastward, now occupied 
by the east Tennessee valley is shown by the Tennessee river at 
Chattanooga, which instead of continuing its course in a southerly 
direction into the gulf of Mexico, by crossing a saddle which is 
only 270-280 feet above its bed, has preferred a channel through 
the Cumberland plateau rising 1400-1500 feet above its bed. It 
is evident also that during the time the Tennessee was cutting its 
•channel through the plateau, this area must have been at a lower 
level than districts farther south, in the region of the saddle 
to which reference has just been made. Ultimately the Tennes- 
see, instead of continuing its course in a southerly direction into 
the gulf of Mexico, makes a great sweep to the northward, on the 
west side of the Cumberland plateau, and joins the Ohio at a dis- 
tance of about forty miles above the junction of that river with 
the Mississippi, thus adding to its course a length of about 800 
miles ! 
Notes and Comments by Aug. F. Foerste, Cambridge, Mass. 
The course of the Tennessee at Chattanooga shows that while 
the river was cutting its channel through the Cumberland plateau, 
this plateau must have lain at a lower level than the land both to 
