1898-99. | THE IROQUOIS BEACH. 35 
elevation and general direction have been determined at a number of 
points toward the east by Dr. Spencer. 
From the sketch just given of the Iroquois beach within York county 
it is evident that the old shore is a quite mature one, almost as much so 
as the present shore of Ontario, and probably implies as long a time for 
its formation. 
The beach deposits vary greatly in thickness and character, according 
to the circumstances of the shore. The greatest thickness observed is 
about 100 feet, just west of the Hunt Club at Scarboro’, where the 
materials are coarse and fine sand with a little gravel ; but thicknesses 
of fifty or more feet arenot uncommon. The two bays described above 
were almost completely filled with sand and silt behind the gravel bars, 
so that now they present the appearance of plains greatly dissected by 
the ravines of the present watercourses. That large quantities of 
materials were deposited at other points on the shore of Lake Iroquois 
is proved by the stratified gravels of this age at Burlington and on the 
Niagara river. 
FOSSILS OF THE IROQUOIS BEACH DEPOSITS. 
In general the Iroquois beach is very barren of fossils as might be 
expected where loose sand and gravel uncovered by an impervious 
layer of clay are exposed to the weather for thousands of years. It is 
only at comparatively low levels, or where the gravel has been 
cemented by lime that fossils are likely to be preserved. The earliest 
finds recorded are those mentioned in 1843 by Hall in New York State, 
where wood and, as he was informed, shells also were found in gravel 
ridges of this age.* The Geology of Canada states that the shells were 
unios. The cutting of the Desjardins canal at Burlington Heights, 
where the Iroquois beach deposits, chiefly coarsely stratified gravel, partly 
cemented by carbonate of lime, have a thickness of 107 feet with Erie 
clay beneath, disclosed a number of bones of mammals, including 
Euelephas jacksont (the mammoth), horns of cervus canadensis (wapiti) 
and the jaw of castor fiber (beaver). The mammoth bones occurred 
seventy feet above the present lake and the other remains seven feet 
higher ;+ or from thirty to forty feet below the level of Iroquois beach. - 
A few years ago the Toronto, Hamilton and Buffalo railway made a 
deep cutting on Hunter street, Hamilton, in order to obtain convenient 
access to the centre of the city. This cutting has since been covered 
over and is called the Hunter street tunnel. When examined by the 
writer the cutting passed through thirty feet of coarse stratified gravel, 
Zo; ‘cigs 
t Geology of Canada, 1863, p. 914. 
