44 TRANSACTIONS OF THE CANADIAN INSTITUTE. [VoL, VI. 
glacial peaty clay, the overlying till having been removed, apparently, in 
this old valley, for a few hundred yards to the east blue till is seen over- 
lying the same peaty clay at a higher level. There are other points 
also, one at a brickyard in the east of the city, where the peaty clay 
seems to have been cut into a cliff before the Iroquois sands were spread 
over it, and half a mile east at Price’s brickyard, the same cliff of clay 
buried in stratified sand may be found, though not so distinctly. If this 
evidence be admitted, the water stood for a long time at least 100 feet 
below the Iroquois terrace after the laying down of the last till sheet. 
It is generally held that during the last retreat of the ice the succession 
of high level lakes was unbroken, and that Lake Iroquois followed Lake 
Warren without any dry land interval. It has been shown by Gilbert 
that owing to differential elevation of the basin toward the northeast 
the water at the southwest end of Lake Iroquois at first stood lower 
than the later level of the beach.* Perhaps the difference at Hamilton 
may be sufficient to account for the weathered till thirty feet below the 
top of the Iroquois gravels, for Hamilton is the farthest point southwest 
of the line running through Rome, N.Y., representing the axis at which 
the water level suffered no change. Toronto is very nearly on that line, 
so that there would have been little or no oscillation of the Iroquois 
water level ; nevertheless there are indications of Iroquois erosion and 
weathering seventy feet or more below the Iroquois beach. Before 
making positive statements regarding this, however, it will be well to 
examine all the localities likely to throw light on the subject, and up to 
the present only a few of them have been studied with this point in view. 
If the fact should be established it may be necessary to assume the 
withdrawal of the ice after the time of the Warren water long enough 
for the erosion and weathering observed, and then an advance of the 
elacial lobe of the upper St. Lawrence valley to the Thousand Islands, 
and a halt at the northeast end of Lake Iroquois sufficiently long for 
the formation of the beach. It would be of great value to examine the 
clay beds or rock underlying the Iroquois beach gravels at other points 
than Hamilton and Toronto, so as either to prove or disprove the 
existence of a low water stage between the time of Lake Warren and 
that of Lake Iroquois as suggested above. 
This splendid old beach, so excellently preserved in both New York 
State and Ontario, whose bars and gravel ridges are traversed by main 
roads for many miles, on whose terraces towns and cities are planted, 
should receive more careful study than has been devoted to it of late 
years so as to solve the interesting problems it presents regarding the 
immediate past of the region. 
= 6th An. Rep. State Reservation at Niagara, pp. 70 and 71. 
