150 FRAGMENTS OF SCIENCE. 
to have arisen that the deep channel of the river Niagara 
below the falls had been excavated by the cataract. In Mr. 
Bakewell's " Introduction to Geology," the prevalence of 
this belief has been referred to. It is expressed thus by 
Professor Joseph Henry in the " Transactions of the Albany 
Institute: " * " In viewing the position of the falls, and the 
features of the country round, it is impossible not to be im- 
pressed with the idea that this great natural raceway has 
been formed by the continued action of the irresistible 
Niagara, and that the falls, beginning at Lewiston, have, 
in the course of ages, worn back the rocky strata to their 
present site." The same view is advocated by Sir Charles 
Lyell, by Mr. Hall, by M. Agassiz, by Professor Ram- 
say, indeed by most of those who have inspected the 
place. 
A connected image of the origin and progress of the 
cataract is easily obtained. Walking northward from the 
village of Niagara Falls by the side of the river, we have to 
our left the deep and comparatively narrow gorge, through 
which the Niagara flows. The bounding cliffs of this 
gorge are from 300 to 350 feet high. We reach the whirl- 
pool, trend to the northeast, and after a little time gradu- 
ally resume our northward course. Finally, at about 
seven miles from the present falls, we come to the edge of a 
declivity, which informs us that we have been hitherto 
walking on table-land. At some hundreds of feet below us 
is a comparatively level plain, which stretches to Lake 
Ontario. The declivity marks the end of the precipitous 
gorge of the Niagara. Here the river escapes from its steep 
mural boundaries, and in a widened bed pursues its way to 
the lake which finally receives its waters. 
The fact that in historic times, even within the memory 
of man, the fall has sensibly receded, prompts the question, 
How far lias this recession gone? At what point did the 
ledge which thus continually creeps backward begin its 
retrograde course? To minds disciplined in such researches 
the answer has been, and will be At the precipitous de- 
clivity which crossed the Niagara from Lewiston on the 
American to Queenston on the Canadian side. Over this 
transverse barrier the united affluents of all the upper lakes 
once poured their waters, and here the work of erosion be- 
* Quoted by Bake welL 
