104 KANSAS ACADEMY OF SCIENCE. 
In front yawns a precipice. It is filled with icy water. A small granite 
boulder of hardest texture rests on a solid limestone ledge in front of the ice-field. 
Water to a depth of 75 feet flows over the ledge. 
The big moving boulder comes shooting over the brink of the ice. The little 
resting boulder is its objective point. The resting boulder is not immovable. 
The moving boulder is not irresistible. The little boulder does not sink crushed 
out of sight into the limestone. The big boulder does not get broken intoa 
thousand pieces and scattered over the surrounding country. The water breaks 
the force of the big boulder’s fall. The little boulder breaks the big boulder’s 
back. 
Or is it broken by the sudden cooling by immersion in the icy water? 
Does sliding any distance over the ice at the rate of 100 miles an hour polisha 
stone as much as sliding the same distance over the ground under the ice at the 
rate of 100 miles in a thousand years? Why not better? 
My story is told. JI have attempted in my feeble way to account for the high 
polish some of these stones have; to account for how boulders within a hundred 
miles or more of the edge of the ice-field may become suddenly transported to the 
terminal moraine on retreat of the ice; and to explain how some of the bould- 
ers may have become broken. 
I here present a map of the counties of Shawnee and Wabaunsee, showing the 
course of the moraine across them, and the probable location of several glacial 
lakes. 
THE McPHERSON EQUUS BEDS. 
By J. W. BEEDE, Topeka, Kan. Read before the Academy January 1, 1897. 
There is a formation of considerable economic and scientific interest located in 
McPherson, western Marion, Harvey, and northeastern Reno counties. A large 
channel! is carved out of the Permian shales, and, in the northern part, Dakota 
sandstone. Its eastern limit is a line trending north and south along the west 
side of Sand creek to a place a few miles north and west of Lehigh, Marion 
county. Here it turns westward about 20 miles, then northward to the Smoky 
Hill river. Its western boundary, beginning at the Smoky Hill river, runs just 
east of Edwards creek to the Little Arkansas river, south of which the sand-hills 
seem to encroach upon its area. It is well shown in the wells at Halstead, and 
in all probability extends to the Arkansas river. The ‘‘ Tertiary Grit,’’ referred 
to by Professor Hay,* just west of Wichita, is probably an outcrop of this forma- 
tion, as, on the margins of the area and the isolated patches, the sand is im- 
bedded in a limy matrix which makes it resemble the Tertiary grit farther west. 
Over the deeper portions of the channel and well to the western edge lies a 
chain of lakes and basins extending from the large basin two miles west of 
McPherson to the Arkansas river, south of Patterson. The area north of the 
Little Arkansas river is about 800 square miles. South of it, it is probably 100 
square miles, exclusive of the sand-hills. 
TOPOGRAPHY. 
The rough surface of the Permian to the east, the Dakota to the north, and 
the peculiar topography of the sand-hills to the southwest, form a marked con- 
trast to the monotonously level surface of the Equus beds area. There are several 
* Bull. 57, U. S. Geol. Surv., p. 34, fig. 9. 
