Part I. Report of progress in 1869, by J. S. Newberry, chief geologist. Part II. Report of progress in the second district, by E. B. Andrews, assist. geologist. Part III. Report on geology of Montgomery County, by Edward Orton, assist. geologist.

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the north side into the old valley, while the deep channel passes on the
south side, under the low lands, on which the city of Louisville is built.
The importance of a knowledge of these old channels in the improvement of the navigation of our larger rivers and lakes is obvious; and it
is possible that it would have led to the adoption of other means than a
rock cutting for passing the Louisville falls had it been possessed by
those concerned in this enterprise.
If it is true that our great lakes can be connected with each other, and
with the ocean, both by the Hudson and Mississippi, by ship canals-in
making which no elevated summits nor rock barriers need be cut through
-the future commerce created by the great population and immense resources of the basin of the great lakes may require their construction.
3d. Upon the glacial surface we find a series of unconsolidated materials
generally stratified, called the "( Drift Deposits."
Of these the first and lowest are blue or red clays (the Erie clays of Sir
William Logan), generally regularly stratified in their layers, and containing no fossils but drifted corniferous wood and leaves. Over the
southern and eastern part of the lake basin these clays contain almost no
boulders, but towards the north and west they include scattered stones,
often of large size, while in places beds of boulders and gravel are found
resting directly upon the glacial surface.
In Ohio the Erie clays are blue, nearly 200 feet thick, and reach up the
hill-sides more than 200 feet above the present surface of Lake Erie., On
the shores of Lake Michigan these clays are, in part, derived from different
rocks, and they then include great numbers of stones.
On the peninsula between Lake Erie and Lake Huron the Erie clays
fill the old channel which formerly connected these lakes, having a thickness of over 200 feet, and containing a few scattered stones.
Above the Erie clays are sands of variable thickness and less widely
spread than the underlying clays. These sands contain beds of gravel,
and near the surface teeth of elephants have been found, sometimes
water-worn and pounded.
Upon the stratified clays, sands and gravel of the drift deposits, are
scattered boulders and blocks of all sizes, of granite, greenstone (diorite
and dolerite), siliceous and mica slates, generally traceable to some
locality in the Eozoric area north of the lakes. Among these boulders
have been found many masses of native copper, which could have come
from nowhere else than the copper district of Lake Superior.
Most of these transported stones are rounded by attrition, but the large
blocks of corniferous limestone scattered over the southern margin of the
lake basin in Ohio show little marks of wear. Some of these masses-10
to 20 feet in diameter-have been transported from 100 to 200 miles southeastward from their place of origin, and deposited 300 feet above the
position they once occupied.