394 
GEOLOGY OF THE FOURTH DISTRICT. 
In support of the hypothesis that falls do retrograde, we may adduce sufficient evidence. 
Observations, during the last five years, upon the waterfalls of Western New-York, have 
furnished positive evidence of their recession. Among these may be noticed the falls on 
Jacock’s run, near Geneseo, and Fall brook, a few miles farther south, both of which have 
evidently receded, from the undermining of the platform over which the water is precipitated. 
The amount during this time is very small, but quite sufficient to be appreciated. 
Lateral streams flowing into ravines or river courses, furnish the most palpable evidence of 
the excavating power of water. The channel of Wolf creek, which comes into the Genesee 
through a perpendicular wall of rock, is a good example of this kind, where the evidence is 
conclusive that the excavating power is alone due to the stream. The junction of a small 
stream with the Genesee, on the west side, below Rochester, furnishes another example of 
this power. This stream has cut its channel through soft shale for fifty feet or more, a bed 
of limestone eighteen feet thick, a bed of shale of equal thickness, and below this another bed 
of limestone nearly equal to the upper one. Many more examples of a similar kind might be 
named, on the Seneca and Cayuga lakes, and their valleys continued to the south. 
All the historical evidence that we possess upon the subject proves the falls to have receded ; 
and, although there have been no monuments established, yet the representations of early 
travellers, when compared with the present condition of the falls, proves that a change has 
taken place, though we cannot be certain of its precise amount. 
The oldest authentic historical account of the falls which I have seen is that of Father 
Louis Hennepin, who travelled in this country in 1678.* The accompanying view of the 
falls is a fac simile of that published in his travels, and though rude and fanciful, it is, in many 
points of view, highly interesting and important. 
It represents a projecting rock upon the west side of the river, which turned a part of the 
water across the main fall, as seen in the sketch. This fact is of great interest as showing 
one important change which has taken place within the historical era; for in regard to a 
portion of the water being projected from west to east, forming a cross fall, there seems no 
doubt, as it is particularly described. In chapter LXX. he says, “ From the end, then, of this 
island it is that these two great falls of water, as also the third, but now mentioned, throw 
themselves, after a most surprising manner, down into a dreadful gulph six hundred foot and 
more in depth. I have already said that the waters which discharge themselves at the cas¬ 
cade to the east, fall with lesser force ; whereas those to the west tumble all at once, making 
two cascades; one moderate, the other violent and strong, which at last make a kind of 
crotchet or square figure, falling from south to north and west to east.” The northwestern 
* This work is entitled “ A New Discovery of a Vast Country in America, extending above four thousand miles, between New- 
France and New-Mexico; with a description of the Great Lakes, Cataracts, Rivers, Plants and Animals; also, the Manners, 
Customs and Languages of the several Native Indians; and the advantages of commerce with these different nations, &c.” Dedi¬ 
cated to His Most Excellent Majesty, William III. King of Great Britain, &c. By F. Louis Hennepin. London, 1698. This 
work was first published in Utrecht in 1697. 
My attention was called to this book and view of Niagara falls by Joseph W. Ingraham, of Boston, who has given much 
attention to collecting the historical accounts of Niagara falls. 
