124 OW. M. Davis—Gorges and Waterfalls. 
must have the same origin, if Professor Kjerulf's theory of the Z 
making of the fjords by dislocation prove correct. But a 
these examples are in regions quite unlike those of the moder- 
ate relief and inconsiderable dislocation that are here to be 
considered. 
The following examples will serve to illustrate the impor- 
tance of the connection between drift and gorges. 
Professor James Hall called attention many years ago to the 
numerous gorges of western New York.* They are nowhere 
0 
Portage there is a broad, alluvial valley, the bottom of an old 
lake; thence to Mt. Morris the stream flows through a’ mean- 
dering gorge over three hundred feet deep, leaping down several 
falls, shut in by steep, rocky banks free from drift. Not far to 
one side, the abandoned preglacial channel may be traced by 
the heavy drift deposits, which when sounded by wells or 
eology of New York, IV District, 1843, 371, 422. Here and beyond, 
extracts are sometimes given almost word for word from the authors. named, but 
+ ce for this origin of Lake Erie and Niagara is summarized in my 
paper on the Classification of Lake Basins, Bost, Soc. Nat, Hist. Proc., xxi, 1832, 
36 recent paper by G. F. 
eter,” is in the Bibliotheca Sacra, April, 1884.—See also p. 32 of this volume. 
Wright on “The Niagara Gorge as a Chronom- 
rere 
