344 A.C. Ramsay on the Glacial origin of certain Lakes 
the plains beyond. 
The Glacial Theory.—F urthermore, considering the vast areas 
over which the phenomena described are common it North 
America and Europe, I believe that this theory of the origia of 
lake-rock-basins is an important point, in addition to prev! 
knowledge, towards the solution of the glacial theory; for Ido 
not see that these hollows can in any way be accounted for by 
the hypothesis that they were scooped by floating ice.” An 
iceberg that could float over the margin of a deep hollow would 
not touch the deeper recesses of the bottom. I am theretor 
constrained to return, at least in part, to the theory me! 
ago strongly advocated by Agassiz, that, in the per ot 
tremest cold of the Glacial epoch, great part of North Americ 
the north of the Continent of Europe, great part of Britain, — us 
Ireland, and the Western Isles,** were covered b 
re 
18 But this is not. essential, unless the lochs are so deep that the ice must have 
been floated up before reaching the deeper parts. ota ser 
+7 T do not % any way wish to deny that much of the glaciation of i, 
ithin the limits of the Drift was effected by floating Tiich it 
large scale, which must have both polished and stri rocks along But the 
ground. i r authors, described this in various memoirs, ©" " oe 
sheets of true Be 
