GEOLOGY OF THE WESTERN DISTRICTS OF CANADA. 505 
village of Chippewa, the massive Niagara limestone now at the top 
will then extend also to the base of the Falls, and its great hardness 
will probably arrest the excavating process, if it should not have 
been previously stopped by the descent of larger masses of the same 
rock from the cliffs above. In this latter case, instead of a fall we 
shall have a rapid of about the same slope as the present rapids 
above the falls, (fifty feet in three-fourths of a mile); but very much 
more broken and irregular owing to the greater size of the masses of 
rock forming the bottom. 
The next question to which we are naturally led, relates to the 
origin of the Falls, but this subject I shall defer till the close of this 
article, when, after describing the principal geological features of the 
region bordering on the head of Lake Ontario, I shall attempt to 
indicate the succession of events which have produced them. 
Strata traced Westwards.—The various members of the series of 
rocks already described, are also exposed in tracing the escarpment 
running parallel to the shores of the lake, from Niagara to Flamboro’. 
The strata le nearly horizontally from east to west, but dipping 
slightly to the eastward, the dip of the lower standstone bed 
{called by the quarrymen the Gray band,) which rests immediately 
on the red marl, being at the rate of twenty-two inches per mile. An 
attentive observation of the section thus exposed will shew the remark- 
able manner in which certain of the beds thin out and die away as 
you follow them westwards; while others not to be discovered at the 
Niagara river are intercalated in the series, and as they are traced in 
a northwest direction attain to a great thickness, still retaining their 
distinctive characters. Thus the great deposit of dark shale, which 
at the Falls shews a thickness of eighty or ninety feet, is represented 
at Flamboro’ by a bed of only five feet thick ; while the encrinal and 
cherty limestone, which at Flamboro’ occupy a most prominent place 
in the group, die out gradually and are scarcely to be detected at the 
Falls.* This same encrinal limestone, which at Flamboro’ is only 
* This phenomenon, which is not peculiar to the Silurian or to any other system, though 
nowhere perhaps more strikingly apparent than in this locality, may, I conceive, be accounted 
for in three ways: Hither, Ist. That in the wide and deep ocean in which these depusits were 
made, certain of them never reached the deeper portions, but subsided along its shores; 
Or, 2nd. It may have been caused by certain portions being too shallow or even upraised 
2bove the surface of the water. Or, 3rdly. After the deposition of the stratum, it may have 
been uplifted so near to the surface of the sea, as to have been worn away by the waves, and 
thus have allowed a succeeding deposit to come directly upon one of preceding date. 
