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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ley, at least, the dip of the rocks is conformable to the original northern slope of the surface.
It is an interesting fact that the Muskingum river, which drains no
inconsiderable part of Eastern Ohio, has its bed during its whole course
above the level of Lake Erie. The height of the surface of Lake Erie,
at Cleveland, above tide water, as given by Col. Charles Whittlesey,
is 564 feet, while the elevation of the mouth of the Muskingum is
571 feet, as given by Col. Charles Ellet, Jr., in his contributions to the
Physical Geography of the Mississippi Valley, published by the Smithsonian Institution. This makes the mouth of the river 7 feet above
the average level of Lake Erie. This is probably 4 or 5 feet too great.
The mouth of the Scioto is 90 feet below the level of the Lake, while
the Ohio river, at Wheeling, W. Va., at low water, is 56 feet above.
Thus it will be seen that the plane of the surface of Lake Erie, if
continued, will pass below the surface of nearly the whole area included
in the Second District.
Col. Ellet gives the fall of the Scioto, from Columbus to Portsmouth,
to be 302 feet. This river would therefore pass below the level of the
surface of the Lake at a point 27.8 miles above Portsmouth. This
supposes, however, that the fall of the river is uniform throughout
its course. The Muskingum river, according to Col. Ellet, falls between
Zanesville and its mouth, at Marietta, 104 feet. This makes that river,
at Zanesville, about 111 feet above the level of the Lake. The Scioto, at
Columbus, is 212 feet above the level of the Lake, or 101 feet above
the Muskingum, at Zanesville.
The valleys of all the principal streams in the District are generally
deep and well defined, and the work of aqueous erosion has been immense. The immediate valley of the Scioto is the broadest, as it is
the most fertile; and next to this, in width and fertility, is that of the
Muskingum. All the streams have innumerable small tributaries, which
have cut for themselves deep channels. A correct topographical map of
Southeastern Ohio would present the peculiar and beautiful dendritic
aspect belonging to all regions where the valleys are eroded and the
drainage rapid. The erosion has been entirely produced by the flow
of waters which have fallen upon the surface of the State, the only
exception to this in the Second District being in the morelevel region in
the northwestern part, where doubtless there have been at work, in the
remote past, erosive agencies which have acted on a vast horizontal
scale. As, in the course of ages, the Ohio deepened its bed, the largest
affluents felt the effects of the increased declivity, and increased the
depth of their channels, and with this came the gradual deepening of
all their smaller tributaries. Hence, with ample time given for the
work, we should expect to find what we now see-the whole District