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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It will be noticed that Col. Foster gives a seam of coal six feet thick under
the limestone in the bed of the river. It is singular that so thick a seam
should never have been carefully explored.
In a section of the strata at Flint Ridge, made by Prof. Lesquereux
and Dr. H. I. Salisbury, and quoted by Lesquereux in the Kentucky Reports, vol. iv., we find a seam of coal 80 feet below the blue Flint Ridge limestone, which is supposed to be the equivalent of the Putnam Hill limestone. This seam is then the equivalent of the seam under the limestone
in the bed of the Muskingum, at Zanesville. The limestone, however, is
not found over it at Flint Ridge. It rests directly upon the conglomerate, according to Mr. Lesquereux. It appears to be the general fact
that along the base of the productive coal measures, wherever we find
the Maxville limestone, we find underneath the finer grained sandrock:of
the Logan group. The sandstones were accumulated in basins of comparatively quiet water, and in the same basins there was often deposited,
on the top of the sandstones, the Maxville limestone. I have nowhere
found the Maxville limestone resting upon conglomerate.
NOTE.-At no other point in my district has coal been found below the Maxville
limestone, and this fact leads me to doubt whether the " blue limestone," 8 feet thick,
given by Col. Foster, is the equivalent of the true Maxville limestone. This point will
hereafter be examined.