226 
PHYSICAL HISTORY OF THE 
can be shown that it connected the shoals of 
Newfoundland with the continent; that Nan¬ 
tucket, Martha’s Vineyard, and Long Island 
made part of the mainland; that, in like man¬ 
ner, Nova Scotia, including Sable Island, was 
united to the southern shore of New Brunswick 
and Maine, and that the same sheet of drift 
extended thence to Cape Cod, and stretched 
southward as far as Cape Hatteras ;—in short, 
that the line of shallow soundings along the 
whole coast of the United States marks the 
former extent of glacial drift. The ocean has 
gradually eaten its way into this deposit, and 
given its present outlines to the continent. 
These denudations of the sea no doubt began 
as soon as the breaking up of the ice exposed 
the drift to its invasion; in other words, at a 
time when colossal glaciers still poured forth 
their load of ice into the Atlantic, and fleets 
of icebergs, far larger and more numerous 
than those now floated off from the Arctic 
seas, were launched from the northeastern 
shore of the LTiited States. Many such mass¬ 
es must have stranded along the shore, and 
have left various signs of their presence. In 
fact, the glacial phenomena of the United 
