356 The American Geologist. June.i.sos 
it seems fair to call for evidence of the most ng nature 
before accepting the ancient peneplains. So lai .>.. can judge 
the evidence is not of this nature. 
Lack of Evidence of Ancient Peneplainsf^ — Several ob- 
servers, both in this country and abroad, have called attention 
to the fact that if a person stands upon a high hill in certain 
regions he looks over a vista of apparently level-topped crests, 
even though between the hills there are many deep valleys. 
This appearance has been described with especial fullness by 
Prof. Davisf and others for the New Jersey and the New 
jEngland highlands. It is argued that these even-crested 
ridges and hills occur in regions of complex rock structure, 
and hence that the explanation cannot be the same as that 
for plateau crests capped by hard rock in a horizontal position. 
From this condition an ancient plain is alarmed, and the 
American school explains it by subaerial denudation, while 
the British school has advocated marine denudation. 
It is true that as one stands upon an eminence and looks 
I over the surface of the surrounding region, the hill tops in 
I these places appear to be quite level. But it is equally true 
I that the same appearance will be produced even where the 
j ridges reach a quite different level. The appearance to the 
neye may be most deceptive. In order to see exactly what the 
j conditions are, I have made a careful examination of the topo- 
j graphic sheets covering the highlands of New Jersey and 
Connecticut, and have constructed a series of profiles across 
the former regions. 
In the case of New Jersey, leaving out of consideration all 
the valleys and all of the lower hills, there is a range of fully 
500 feet in the elevation of the higher crests, and there is 
about the same range along the crest line of the very even- 
topped Kittatinny mountains. There is a difiference of fully 
1 900 feet between the crests of these two neighboring high- 
lands: A series of nine parallel profiles from east to west in 
this region shows a very distinct lack of uniformity in the 
elevation of the upland crests, even if all the lower hills are 
eliminated. 
*It is to be understood that this refers only to the best established 
peneplaiiis, not to those whose proof is most doubtful. 
tSee previous references. 
