216 FRAGMENTS OF SCIENCE 



it lias been able to accomplish, while the Horseshoe Fall 

 was cutting its way southward across the end of Goat 

 Island to its present position. The American Fall is 168 

 feet high, a precipice cut down, not by itself, but by the 

 Horseshoe Fall. The latter, in 1842, was 159 feet high, 

 and, as shown by the map, is already turning eastward, to 

 excavate its gorge along the centre of the upper river, 

 p is the apex of the Horseshoe, and T marks- the site of 

 the Terrapin Tower, with the promontory adjacent, round 

 which I was conducted by Conroy. Probably since 1842 

 the Horseshoe has worked back beyond the position here 

 assigned to it. 



In conclusion, we may say a word regarding the proxi- 

 mate future of Niagara. At the rate of excavation as- 

 signed to it by Sir Charles Lyell, namely, a foot a year, 

 five thousand years or so will carry the Horseshoe Fall 

 far higher than Goat Island. As the gorge recedes it will 

 drain, as it has hitherto done, the banks right and left of 

 it, thus leaving a nearly level terrace between Goat Island 

 and the edge of the gorge. Higher up it will totally drain 

 the American branch of the river; the channel of which in 

 due time will become cultivable land. The American Fall 

 will then be transformed into a dry precipice, forming a 

 simple continuation of the cliffy boundary of the Niagara 

 gorge. At the place occupied by the fall at this moment 

 we shall have the gorge enclosing a right angle, a second 

 whirlpool being the consequence. To those who visit Ni- 

 agara a few millenniums hence I leave the verification of 

 this prediction. All that can be said is, that if the causes 

 now in action continue to act, it will prove itself literally 

 true. 



