IOWA ACADEMY OF SCIENCES. 
69 
2. Two borings were made on a little plateau about one-half 
mile east of Lime creek, and notes on a well near by were taken. 
3. Two borings were made on the timbered ridge south of 
Forest City, and several cuts along the Minneapolis & Sfc. Louis 
railroad and at the gravel pit two miles south were examined. 
4. Two borings were made between Forest City and Lake 
Edwards (in Hancock county), one near the top of a hill on 
which a few bur oak shrubs had gained a foothold, and one on 
lower ground. Observations w'ere also made in cuts along 
wagon roads west of Forest City. 
5. Well diggers were consulted at Forest City. 
c. At Spirit Lake, in Dickinson county, exposures along the 
lake shores and cuts along railways and wagon roads were 
studied. 
d. Near Granite, in Lyon county, five borings were made at 
various altitudes, about one mile west of Granite and south of 
the railroad, and observations were made in the railroad cuts 
between Granite and the Big Sioux river. 
The results were fairly uniform and are here briefiy sum- 
marized. 
The succession of strata in the great majority of cases was 
as follows: 
1. A fine black surface soil, sometimes mingled with fine 
sand, varying in thickness from six inches to two feet. 
2. A compact yellowish layer of clay resembling loess, but 
sometimes with grains of sand and very small pebbles inter- 
mingled, and devoid of fossils. This is sometimes quite absent, 
but again reaches a thickness of nearly two feet. 
3. A layer of yellow boulder-clay, with numerous boulders, 
these often several inches in diameter, occasionally much larger. 
4. The boulders interfered with the borings, but where 
deeper sections could be observed it was found that this layer 
varied from five to fifteen feet in thickness.* 
Where borings were made in low or fiat grounds it was found 
that strata 1 and 2 averaged a little greater in thickness, and 
stratum 1 was rather more frequently mingled with sand. 
The borings at Clear Lake and east of Forest City were made 
in the timber. In all these stratum 1 was greater in thickness 
and was mostly made up of finer material. 
* Beneath this layer at Forest City occur pockets of sand, underneath which is a 
blue boulder-clay of great thickness, said by the well diggers at Forest City to vary 
from sixty to 100 feet in that vicinity. 
