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IOWA ACADEMY OP SCIENCE 
THE POST-KANSAN SURFACE DEPOSITS 30 FEET. 
2 ft. Soil, a black loam (loess and humus.) 
28 feet. A brownish loam for ten feet, porous, a mixture of clay and 
microscopic particles of quartz, streaked with brown oxide of iron in 
root-like tubes and with very thin layers of a dark brownish sand; 
entirely free from pebbles. At thirteen feet from the surface the deposit 
is less clayey than above and contains more numerous streaks of brown- 
ish sand. Two feet deeper (at 15 ft.) the deposit is slightly bluish; then 
for two feet it is grayish and more dense ; then for three feet is a dense 
blue clay free from sand and impervious to water, but still free from 
effervescence and free from pebbles. (The ground water, the surface 
of which was encountered at eight feet, rests on the impervious clay at 
this level.) For the next eight feet (to 26 ft.) the clay is of a light 
grayish blue, still free from pebbles and effervescence. At first (at 21 
ft.) it is somewhat more gritty than above and contains traces of a brown 
oxide of iron. The first four feet of the eight caved badly, large water- 
soaked masses (wet from below upward) scaling in vertical sheets from 
the sides of the well, as the uppermost phase of the loess does by the 
roadside. 
The first pebble encountered was a small angular red granite at 
twenty-six feet,, dimensions 5-16x3-16x2-16 of an inch. In the next two 
feet (to 28 ft.) the deposit (the lower loess) contains a fine sand and 
spherical grains of quartz 1-16 of an inch in diameter. The remaining 
four feet to the sand (sub-loessial) is grayish in color and with a grayish 
and brown sand through it. In the bottom of this deposit was a pebble 
3-8x2-8xl-8 of an inch, and grains of quartz up to 1-8 of an inch in dia- 
meter. 
THE SUB-LOESSIAL SAND. — 2 FEET. 
Sand, pure, brown and gray. At the well to the east this sand is al- 
most wanting. At the well farthwest west the sand is nearly four feet 
thick. At the intermediate Avells it is about two feet thicks the bottom 
of the sand sloping to the west. 
KANSAN DRIFT. 54 FEET. 
Directly beneath the sub-loessial sand is a light brownish blue stiff 
clay in which the first concretion of calcium carbonate was found, and two 
small pebbles of greenstone, then a bowlder too large to get into the auger, 
and, at 33 feet, a dark blue clay with the first distinct effervescence of the 
clay itself, this effervescence continuing with each auger full for fifty- 
