SURFACE GEOLOGY. Al 
bowlders over the southern part of the State. It should be remembered, 
however, that it is not claimed that all the large bowlders were trans- 
ported by icebergs; simply that many of them must have been so trans- 
ported, and probably most of them were. The accompanying wood-cuts 
will better explain my idea of the method of transport of these bowlders 
than I can do it in words. 
NORTH SHORE OF INLAND SEA, WITH GLACIER AND ICEBERGS. 
LY 
ae ‘ae 
en rocks Cae drift. Laurentian hills and glacier. 
That icebergs can and do transport great quantities of bowlders, gravel, 
and sand, is attested by thousands of observers who have seen them doing 
it. For example: in 1822 Captain Scoresby saw a large iceberg drift- 
ing along, loaded with earth and rocks, conjectured to be from 50,000 
to 100,000 tons; and Captain James Kent, quoted in Kane’s Arctic Hxpe- 
dition, speaks of millions of tons of stone and other solid matter carried 
by icebergs. These materials are sown broadcast over the bed of the 
North Atlantic and the banks of Newfoundland, just as formerly over 
the shallows bordering the southern shore of our fresh-water inland sea. 
KAMES. 
Along the summit of the watershed, between the Lake and the Ohio, 
from the eastern to the western margin of the State, accumulations of 
Drift material occur, which are peculiar in their character and position, 
and of which the history is less easily made out than that of any other 
portion of the Drift series. These are beds, banks, and hills of sand, 
gravel, and bowlders, with little admixture of clay. In many localities, 
these materials are heaped up into rounded, or, more often, elongated 
hills, from 50 to 100 feet in height, to which the name “ hog’s-back ” is 
very frequently applied. Sometimes several of these hills are grouped 
together, forming an undulating surface, with inclosed basins, which are 
often occupied by lakes, or peat bogs; though frequently without water, 
from the porous nature of the material which surrounds and underlies 
them. A large number of the peat bogs, lakes, and marshes, which con- 
stitute such a marked feature in the topography of the summit of the 
watershed, are surrounded by gravel hills, and owe their existence to the 
