206 Notes on the Drift and Alluvium of Ohio and the West. 
3d. “Sand and gravel drift,” containing granite bowlders (in 
small numbers) of large size, and unconformable to Nes. 1, 2, and 
the other rocks. 
Ath. The “valley drift,” composed principally of debris of the 
adjacent rocks, and occupying the lower parts of the great valleys 
e. 
5th. “ Lacustrine deposits,” occupying the basin of the lakes, 
and for Lake Erie divided into 
(Ist.) The “ blue marly sand.” 
2d.) Coarse sand and gravel. 
6th. Boulders. 
7th. Alluvium. 
Of course these beds or strata are not found in every part of 
the country, and all superimposed on each other. In places, and 
over much the largest area, the “blue hard pan,” being the low- 
est, covers the indurated rocks. 
ometimes the “yellow hard pan,” overlapping the blue, ex- 
tends beyond it, and where the blue is wanting, rests on the sub- 
jacent rocks. So with the next oldest bed, the “sand and gravel. 
drift,” which forms the surface and soil in a large portion of the 
state. The blue and yellow hard pans thinning out and disap- 
pearing, the drift beds fill the place of the lowest stratum, and 
come in contact with the older rock formations. In the great 
wheat counties of Columbiana, Stark, Wayne and Richland, this 
member is very thick, and furnishes a loose, warm, easily tilled 
soil, peculiarly adapted to that grain. 
The thickness of these three beds is very variable, seldom ex- 
ceeding one hundred feet, and the yellow is commonly passed 
through, where it is the surface bed, in digging wells for water. 
Their thickness is as great in the highest portions of the state, 
elevated from 600 to 800 feet above Lake Erie, or 1150 to 1350 
feet above the ocean, as elsewhere. 
No. I.—Bed No. 1 is a very compact mass of blue clay, marl 
and sand, including great numbers of small, partially water worn, 
crushed and striated pebbles, principally fragments of blue lime- 
stone and primitive rocks. It has also specimens of the Silurian 
and secondary rocks. It contains lime, so much as to effervesce 
with acids, and to hasten vegetation when applied to land. 
sides its strong blue color, it is characterized by imbedded timber, 
dirt beds, leaves, sticks, and what are called by well diggers, 
“ orape vines.” 
_It is so solid, as to be almost impervious to water, and is very 
difficult to excavate. Water is frequently struck near its surface, 
after penetrating the overlying yellow hard pan. 
The pebbles are only partially rounded, the angles being blunt- 
ed and worn, but the stone not worked down to a spherical or el- 
liptical form, indicating less movement and transportation than 
