1875.] Niagara. 153 
of a mile from the falls before the glacial period. It may 
have existed to within a few yards of the falls, for anything 
that can be seen to the contrary, whilst, in favour of such 
a supposition, there may be advanced the great width of the 
gorge up to the commencement of the horse-shoe fall, the 
very small indentation that the American fall has made in 
the side of the gorge over which it leaps, and the appearance 
the plan of the falls presents, that the river is now cutting 
back a much narrower gorge, one as narrow as that leading 
to Queenstown from the whirlpool. 
I hoped to have been able to find at Goat Island some 
evidence bearing on this question, as both Lyell and Hall 
have described river gravels capping the till there, and also 
indications of a pre-glacial channel excavated in the si- 
lurian rocks, but the whole of the island was covered with 
a glassy surface of ice produced by the frozen spray from 
the cataract, that made it most difficult to get about the 
sloping banks, and masked the beds I wished to examine. 
On the Canadian side there rises a high ridge of till, over- 
lain by a thick bed of boulder clay, with large stones; and 
on the American side, there is what appears to be a con- 
tinuation of this ridge, now cut through by the river. 
Around this ridge, on the American side, there are indi- 
cations, as I have already mentioned, that the river once 
flowed. Goat Island seems to be a remnant of this ridge, 
and I imagine that it has been pierced, not from above, but 
from below, that it overlaid the pre-glacial gorge, and was 
undermined in the same way as the clay filling up the end 
of the old gorge has been at the whirlpool. This and other 
questions that arise I must leave to observers with more 
time at their disposal, and a more favourable season of the 
year to make their investigations than I enjoyed. The 
observations that I made are the result of three days’ holiday 
from business, and I am sure, from what I saw, that three 
months close application would not exhaust the many points 
of interest that present themselves. The geologists of 
Canada and New York could not have a more interesting 
question to work at than this, and if they did no more than 
correctly and fully map out the gorge, the terraces, and the 
river ridges, they would confer a great benefit on geological 
science. Thezabsence of such maps I found to be a great 
drawback to my investigations. ‘The only part of the gorge 
that has been surveyed with minute accuracy is that at the 
falls. This was done by Professor Hall, assisted by com- 
petent engineers, in 1842, and permanent marks were at the 
same-time fixed in the rocks. The first step of a new survey 
