SURFACE GEOLOGY. Oi 
ever, entire, as will be shown hereafter, for other agents have been in 
action since the melting away of the glaciers, to distribute still further 
the materials which they ground up and transported. It may be said in 
a general way, that the glacial scratches are found over all but the south- 
-eastern third of the State of Ohio; the limiting line running along the 
north side of Columbiana county, thence through the center of Stark, 
crossing the corner of Wayne, and passing diagonally through Holmes, 
Knox, Licking, Fairfield, Pickaway, and Ross; thence westerly through 
the northern part of Highland, Clermont, and Hamilton, into Indiana. 
North and west of this line glacial marks may be detected in nearly 
every county. A great number of observations have been made upon 
the bearing of the glacial strie by Col. Whittlesey, the members of 
the Geological Corps, and others. From these it appears that they con- 
stitute two systems, one of which belongs to the highlands of the water- 
shed and the glaciated area south of this, of which the prevailing direc- 
tion is §. 20° to 30° E., or, more accurately, from N. to $.45° E. In some 
exceptional cases there is locally a marked deviation from the normal 
bearing of this system, as will be seen by reference to the map of the 
north-eastern counties, prepared by M. C. Read, and given below. We 
may, however, refer all these deviations to the influence of local topog- 
raphy, and the general bearing of the ice-marks is such as to show a 
connected ice-sheet, of which the motion was from N. 20° to 30° W.., to 
S. 20° to 80° EK. That this movement of the ice was from the north 
southward, is demonstrated by the transportation of northern rocks into 
and through our State, and of blocks and fragments of indigenous rocks 
southward of their points of outcrop. 
The second system of grooves is confined to the lake-basin and the 
north-western counties of the State. The direction of these grooves— 
which are remarkably deep and continuous—will be seen from the sub- 
joined table: 
DIRECTION OF GROOVES. 
| 
LOCALITY. ROCK. NUMBER OB- BEARING. 
SERVATIONS. 
Put-in-Bay Island .....( Newberry) ...; Waterlime ......... 0.020066 20 S. 80° W. 
ne ‘“* intersecting series AE DY Ws ORS 1 S. 15° W. 
Kelley’s Island ......... (Newberry)...| Corniferous limestone... 12 S. 80° W. 
ie i ry ” ry Hig 1 S. 60° W. 
Sandusky City i ih i oe 4 8. 78° W. 
66 (3 : éé ae (5 66 92 S. 80° W. 
é x4 6¢ ere, 66 66 1 S. 81° W. 
si fy ae Se te ¢ Sei 1 ish (ay Ni 
Bellville, Sandusky county “‘ Sai ACELIIIN Claes. seceesset os. 1 S. 65° W. 
Genoa, Ottawa county (Gilbert) ... in and Niagara.. 2 S. 65° W. 
