Rcscardics relating to the Great Lakes. — Spencer. 1 1 3 
physical conditions of the ground seem to me very unfavora- 
ble." Prof. G. K. Gilbert, on June 15, 188 1, wrote: "My 
first geological field work was in the drift of the Erie basin, 
and the problem of the origin of the basins of the great lakes 
has always had great attraction for me. Had I been able to 
understand its solution, my working hypothesis would have 
been that which you have demonstrated so thoroughly. * ''' 
* The matter has certainly never received a demonstration 
until your paper appeared. * * *" 
At this time the writer was struggling to find the outlet of 
the basins, and looked in every possible direction for buried 
channels without avail. While the St. Lawrence valley, be- 
yond the outlet of lake Ontario, was evidently only a continu- 
ation of the drowned valley occupied by the lake, and while 
the lower St. Lawrence indicated an elevation of the conti- 
nental region to more than 1,200 feet (when the canon of 
the Saguenay was being excavated), the evidence of the local 
oscillation of the earth's crust was not yet forthcoming. The 
deep caiion of the Dundas valley, and the observations of Prof. 
Gilbert that the Irondequoit bay was drowned to a depth of .70 
feet was taken as evidence of terrestrial oscillation, but later 
the writer found that the St. Lawrence, after leaving Ontario, 
was in part flowing over a valley buried or drowned to a 
depth of 240 feet; accordingly the Dundas and Irondequoit 
valleys were no evidence of local oscillation, which had to be 
found elsewhere. 
In concluding a notice of this early work,* the modern 
aspect of the Niagara river was emphasized, and the valley of 
St. Davids was regarded as of inter-glacial origin — in defer- 
ence to the prevailing theories of the time — in place of being, 
as is now known, the channel of an insignificant stream of 
greater antiquity. The Finger lakes of New York were ex- 
plained as closed up valleys which had formerly drained the 
rivers of the highlands of New York, as for example Seneca 
lake, which has since been found to be the ancient course 
of Chemung and its tributaries. About this time the writer, 
from the data collected by the Geological Survey of Pennsyl- 
*A short study of the Features of the Great Lakes, etc. J. W. 
Spencer. Proc. A. A. A. S., vol. XXX, 1881, pp. 131-146; and Surface 
Geology of the Region about the western end of lake Ontario. J. W. 
Spencer, Can. Nat., vol. X, 1882, pp. 213-236, and 265-312. 
