NIAGARA FALLS. 
395 
end of Goat island is also represented as extending perpendicularly to the water ; and though 
we can hardly credit this, we can conceive how such an error may have been committed, 
when the spot was inaccessible. 
In 1750, Kahn, a Danish naturalist, visited the falls, and his description and view is publish¬ 
ed in the Gentleman’s Magazine in 1751. His general description corresponds with that of 
Father Hennepin, though there was at that time no third cascade. The period of his visit 
was seventy-two years after that of F. Hennepin, and he distinctly alludes to the projecting 
rock, which forced the water out of its direct course, causing it to fall across the great fall. 
He speaks of this rock having fallen down a few years previous, and in his view of the falls 
the spot is indicated. In this interval of seventy years we find that the recorded observations 
of these two travellers prove precisely the same kind of change to have taken place, as we 
suppose to have occurred previously, and which has subsequently altered the outline and 
position of the falls. 
We have not space here to introduce all the subsequent accounts of Niagara falls which 
have been published, neither would they furnish us with arguments bearing upon their reces¬ 
sion. 
In 1824,* Prof. Eaton gave a section of the rocks from Lewiston to Lake Erie, which, with 
the omission of the Onondaga salt group, corresponds with subsequent observations. This is 
the first account of the falls which I have seen where the geological structure of the place is 
given. 
In the 28th Yol. of the American Journal of Science and Arts, Prof. H. D. Rogers has 
given a very full description of the falls, and the geology of the surrounding country, together 
with his views regarding the formation of the chasm of the Niagara, and the future recession 
of the cataract. 
Mr. Hayes, in his paper on the geology and topography of Western New-York,f has pre¬ 
sented many interesting facts and speculations relating to the falls and the production of this 
chasm, as well as the fluviatile deposit of Goat island and the eastern shore. 
We have now to consider another class of phenomena, which aid us in our conclusions 
regarding the recession of Niagara, proving at least that the water has extended much farther 
in the direction of Lewiston before the present gorge was excavated. The nature of this 
evidence I pointed out in my report on the Fourth Geological District of New-York, in 1838, 
pages 271, 272, and 273. At that time, I was not aware that the same phenomena had before 
been noticed, though I have since learned that the existence of freshwater deposits on Goat 
island was known some years previous. Whether the important inference had been deduced 
from this fact or not, I do not know. 
Goat island stands upon the top of the precipice separating the two falls; it is formed by 
the accumulation of gravel, sand, and clay, upon the surface of the limestone, and is evidently 
* Geological and Agricultural Survey of the District adjoining the Erie Canal, Part I. page 149. 
f Am. Jour. Science and Arts, Vol. XXXV. No. 1. 
50* 
