IOWA ACADEMY OF SCIENCE 
233 
west on the same road is an exposure of about the same thickness. 
Two miles east on the northeast quarter, section 35-96-6, at the 
head of a small slough, several granite boulders lie at the surface. 
At one and three-quarters miles north of Postville on the Waukon 
road, near the top of a hill, a foot or two of yellow till is exposed. 
Other unmistakable deposits in Allamakee county have been 
noted as follows : 
At top of hill on road from Postville to Waukon, on the north 
side of Yellow river, on section line between sections 34 and 35, 
township 97 north, range 6 west, a heavy deposit of red clay con- 
taining a small amount of drift gravel, with greenstone, quartz and 
granite pebbles quite abundant at the bottom, is exposed. 
About 80 rods farther north, on the same road, is a deposit of 
clay, containing much gravel and pebbles of the usual drift vari- 
eties, quartz predominating. Small agates are quite common. 
Two miles west of Waukon at the bottom of the ditch on the 
north side of the road, buried under ten feet of loess, is exposed 
a few inches of red clay containing drift gravel and pebbles of 
greenstone and quartz with a few of granite. 
On the northwest quarter of section 11-96-6, at a height of 
about fifty feet above the flood plain of Yellow river and about 
one-fourth mile from it eight to ten feet of very red clay contain- 
ing much quartz and greenstone gravel is exposed in a roadside 
bank. 
In Union Prairie township, township 98, range 6 west, Alla- 
makee County, the following exposures may be seen: 
On the north side of the road, on the northeast quarter of section 
30, a few inches of red clay containing granite and other drift peb- 
bles lies immediately on the top of the Galena limestone. On the 
south side of the road at the same place is a granite boulder 18 
inches in diameter. 
By the side of the road, on the southeast quarter of section 13, 
occasional pebbles of greenstone and granite are found. 
Lying just under the roadside fence on the west side of the road 
where it crosses the southwest quarter of the northwest quarter 
of section 1, is a granite boulder over two feet in diameter. The 
road here follows the top of a high and narrow divide between 
Patterson and Silver creeks. 
In Winneshiek County, on the top of the hill just south of De- 
corah, on the Calmar road, several feet of what is probably Iowan 
drift, or outwash from it, are exposed. Small granite boulders and 
pebbles are very abundant in a stiff, sandy, yellow clay. 
