No. 200.] 
371 
belongs to Mr. Whitmore, one and a quarter miles northwest of Lock- 
port. The stone quarried for flagging occupies about five feet in thick- 
ness of the upper part of the strata; the stone separates into thin strata 
or layers commonly of the thickness of two to four inches, but often 
not more than the eighth of an inch, 
These stone are frequently obtained twenty feet square, and no more 
than four inches thick. One in the collection of the State, is six feet 
long, four feet wide, and little more than an inch thick. From its even 
surface this stone is admirably adapted to the purposes for which it is 
required, and the purely siliceous texture renders it extremely durable. 
It is now much used in Buffalo, Lockport and Rochester. 
JYiagara Falls and River. 
For want of time to procure the necessary engravings, the full descrip- 
tion and illustration of this mighty cataract and its effects will be defer- 
red until another report. That the falls have once been at Lewiston is 
unquestionable, if we can depend upon the monuments of a once still 
more mighty river. 
The gorge through which this river passes at Lewiston, presents the 
rocks in the following order from the top downwards: limestone twen- 
ty feet; shale eighty feet; limestone twenty feet; red marl and sand- 
stone seventy feet, (the upper layers only hard;) hard gray sandstone 
twenty-five feet; red marl to the level of the river and far below. 
These rocks dip to the south, and at the falls have all disappeared be- 
neath the river, except the upper limestone and a part of the shale be- 
low. The limestone, which is twenty feet thick on the top of the ridge 
at Lewiston, is eighty feet at the falls. The great height of the falls 
when at Lewiston, and the character of the rocks below, must have 
caused a much more rapid rate of recession at that period than at the 
present. The height of the falls has decreased as they have progressed 
southward, in consequence of the dip of the rock in that direction, 
This cause has gradually lowered the waters of Lake Erie, and will final- 
ly leave it entirely dry, except the channel of the river. There is, how- 
ever, no possibility of a great deluge occurring from the sudden drainage 
of this lake, as stated by Mr. Lyell and other geologists. 
If the southern shore of Lake Erie were formed by a vertical wall of 
rock extending to the bottom, this catastrophe might be apprehended; 
but as it is, the bed of the lake where the Niagara river leaves it is solid 
limestone, sloping south towards the centre. We perceive, then, that the 
