and Physical Stnictnre of the adjacent Country. 129 



shoe Fall. The shock was felt at a considerable distance : the 

 noise was like a distant clap of thunder. 



The disintegration of the rocks must continue until the 

 Falls reach Lake Erie, provided the present causes continue 

 to operate. Goats' . Island, which now separates the Falls, 

 will, perhaps, as the waters recede on each side of it, remain 

 in the midst of the fallen flood, a high, perpendicular, inac- 

 cessible rock : a lasting monument of the destructive power of 

 that element which now thunders at its base. 



It may, perhaps, be said that this deep chasm or chan- 

 nel, through which the river runs on its descent, was a rent 

 made by an earthquake. This supposition would avail if the 

 strata were deranged, but the reverse is the fact. The strata 

 on each side are parallel and on the same level, and bear evi- 

 dent marks of the action of some powerful instrument having 

 cut through them in a perpendicular direction : that instru- 

 ment was water. The wall-like appearance of the rocks on each 

 side of the river is precisely the same at the Falls, as at the 

 commencement of the chasm at Queenstown. 



By the lockages on the Erie and Oswego canals, lately 

 constructed, it appears that the elevation of Lake Erie above 

 Lake Ontario is 290 feet ; and that the elevation of the former 

 lake above the river Hudson, at Albany, is 575 feet. The river 

 at Albany is 1 50 miles distant from the sea. 



Since it is a well established fact that the Falls have re- 

 ceded considerably within the memory of man, and are, by 

 slow but progressive steps, cutting their way backwards to 

 Lake Erie, the mind is led to anticipate the period when the 

 present chasm will extend to that lake, and the consequences 

 which must result from such an event. 



My father, in a former edition of his Introduction to Geo- 

 logy, published in 1815, offered some observations upon this 

 subject, the justice of which seems confirmed, in a remarkable 

 manner, by the recent interesting researches of Mr. Lyell, on 

 the fresh-wa;ter formations in the lakes of Scotland : — " Since 

 the banks of the Cataract of Niagara were inhabited by Eu- 

 ropeans, the distance has been progressively shortening be- 

 tween the Falls and Lake Erie. When it has worn down the 

 intervening calcareous rocks, and effected a junction, the 

 upper lake will become dry land, and form an extensive plain, 

 surrounded by rising ground, and watered by a river or 

 smaller lake, which will occupy the lowest part. In this 

 plain, future geologists may trace successive strata of fresh- 

 water formation, covering the subjacent crystalline limestone. 

 The gradual deposition of minute earthy particles, or the 

 more rapid subsidence of mud from sudden inundations, will 



Vol. III. — No. 12. k 



