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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5. MINERAL PAINTS.
The materials from which mineral paints have been manufactured in
this portion of the State are all obtained from the beds of Drift. The
second variety of blue clay, already described, is principally used for
this purpose.
A company has been organized at Miamisburg for two years, for the
manufacture of these paints, and their sales last year amounted to over
100,000 lbs. A considerable proportion of lead, however, is included
under this aggregate. The bed of clay which is turned to most account
is situated on Hole's creek, at no great elevation above the Miami river.
The clay seems to be identical in composition with the heavy bank near
Springfield, and closely resembles the "Milwaukee brick" clay in composition. As to the durability of these colors, it is too early to decide.
It is suggested by painters in Cincinnati, where the coal smoke renders
frequent re-painting necessary, that even if they are decidedly inferior
to lead in respect to durability, they can still render very useful service
because of their greater cheapness.
Many of the gravel beds of the Drift contain accumulations of ochre
more or less extensive, and occasionally deposits of the same substance
are found unmixed with gravel. The ochre can be separated from the
gravel by washing, and proves to be of fair quality.
A large deposit of this ocherous gravel is to be found on the north
bank of Twin creek, one mile east of Germantown, Montgomery county.
It has been worked for two years, and a considerable quantity of the
paint has been brought into market. A bed of brown coal, that occurs
in the same gravel bank, has been turned to account for the manufacture
of black paint. Mastodon remains, and phosphate of iron, are found
also in this locality. Taking all things into the account, no more interesting section of the Drift is to be found in this region than the "Germantown Ochre Bank."
6. GRAVEL.
It is not easy to set a proper estimate upon the beds of sand and
gravel of the county, until a comparison is instituted between a region
well supplied with such accumulations and another, which is destitute
of them.
The gravel knolls and ridges with which, in the southern and eastern
portions of the county, almost every farm abounds, affords very desirable
building-sites, and are generally selected for such purposes.
Sand of the best quality, for mortar cement and brick making, is everywhere within easy access.
An inexhaustible supply of excellent materials for road-making-what
is frequently designated "clean limestone gravel," though in reality