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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true of all the smaller Ohio tributaries, such as Raccoon, Little Muskingum and Duck creek, which do not have their heads in the central
drift region.
In the terraced drift we find two classes of materials-the hard and
the comparatively soft. The former is composed of diorytes and other
granitoid forms, quartzites and other metamorphic rocks, and the cherty
portions of limestones. The latter is made up of softer sandstones,
slates and bituminous coals. I have found small bowlders of fine grained
Waverly sandstones, which for fineness of texture, and softness under
the chisel, and perfection of color, I have never seen surpassed. Their
original home was in the Waverly formation, and not very far to the
north; for such is the softness of the material, that they could not long
have survived the friction of rolling in currents of water, surrounded by
harder bowlders, much less the more wasting friction of propulsion by
glaciers, under enormous ice-pressure. We sometimes find similar soft
material only very slightly eroded.
In the large terrace formed at the confluence of the Muskingum and
Ohio rivers, on which the town of Marietta is built, we often find large
quantities of pebbles of bituminous coal. Bushels could sometimes be
taken from a single spot, of all sizes, from four inches in diameter downward. Bituminous coal being soft and easily eroded, the coal of these
pebbles must have been torn from its native seam at some point in our
Ohio coal measures but a short distance up the Muskingum, probably
not above Zanesville. It has been estimated that lumps of coal of
medium size, dropped into the Ohio River from steamboats and barges,
are worn away to nothing in rolling on the bottom, a distance of from
fifty to one hundred miles. Pebbles and bowlders of Ohio coal measure
sandstone are also often found in the drift terraces on the Muskingum.
It will be remembered that this river holds its course chiefly within the
limits of the coal formation.
No careful instrumental surveys of the altitude of the terraces above
the streams has as yet been made, but they probably range from 40 to 80
feet above the present average level of the waters. The terraced drift
is never found far up any of the tributaries of the streams which have
carried down the materials. It is sometimes crowded a short distance
into the mouths of tributaries. We sometimes, however, find the drift
some distance from the present channels of the rivers, and back of the
immediate river hills; but in all the cases of the kind I have examined,
the drift is in old channels, or in new ones formed at the time by very
high water. An example of this may be seen in the so called "plains "
between Salina and Athens, in Athens county. Here an old channel,
west of the Hocking river hills, was entirely choked up by the drift.
Another and less marked exhibition of this is at Newport, Washington