230 
IOWA ACADEMY OF SCIENCE 
valley on the east. Just to the north of this small pond is a 
rather large alluvial cone and fan composed of material washed 
out along ravines and deposited in such a way as to dam the 
drainage along the bluff. To the south of the pond a smaller 
deposit from smaller ravines determines the western limit of 
the pond, leaving a shallow, circular depression in which water 
accumulates in wet weather. The pond is not a bayou. 
In the upland which bears evidence of Wisconsin drift topog- 
raphy several tests to determine the depth of weathering indi- 
cated an absence of lime. In many places along the road a sub- 
stratum of stratified sand was observed through which water 
might transport lime leached from above. Had tests revealed 
the presence of lime in the upland the fact would have consti- 
tuted additional evidence of Wisconsin drift; but the absence 
of lime in so thin and porous a surface deposit is not surprise 
ing. It is possible that deeper exposures than are to be found 
in the upland may still remain unleached. In the low divides 
a mile west of Valley Junction the effect of leaching was found 
to a depth of two feet and eight inches, effervescence occurring 
below that depth. 
From the evidence now obtainable it appears that the area of 
Wisconsin drift extends through sections 23, 26 and 35, and 
probably into 36 on the east and 34 on the west. In all direc- 
tions from this area the erosional topography of the Kansan 
drift area is conspicuous. If any Wisconsin drift were ever 
there it has been eroded away since, or its; presence rendered 
inconspicuous by the complete drainage of the upland. 
The stratified sand, so evident along the road, is beneath the 
Wisconsin drift, not an outwash from it.^ Along the road in 
the southern part of section 14 it underlies a bed of loess. While 
it is possible that the sand may have been washed out from the 
Wisconsin drift prior to the extension of that drift sheet south 
of the river (in which case the loess would be post-Wisconsin) 
that is not probable. Similar deposits of sand are found in 
numerous places on the top of the Kansan drift where there is 
no evidence whatever that the Wisconsin drift or an outwash 
from it could have extended there. 
Us this sand continuous beneath the Wisconsin drift to the Iowan drift ; 
and is it then continuous with sand above or below' the Iowan drift? This 
is an important question, in view of recent discussions. Up to the present 
the question remains unanswered. 
