IOWA ACADEMY OF SCIENCE 
191 
Whatever else may be uncertain, it is perfectly sure that the best 
waters obtained as ydt from the deep wells have been obtained in 
the northeastern portion of the state. This section bounded on the 
west and south by a line from the Iowa lakes south to a little north 
of Des Moines, and then east to Muscatine, would contain all the 
deep wells which give abundant supplies of moderately good water. 
Outside of this area the deep well waters are scanty in amount or 
highly mineralized, and in fact, they are usually both. 
It is certain also that the good waters from deep wells come 
from the lower sandstones. Downward or in the order in which 
they are penetrated by the drill they are, the St. Peter, the New 
Richmond, the Jordan and the Basal Sandstone. These strata out- 
crop to a small extent in the extreme northeastern corner of the 
state. In Wisconsin and Minnesota their surface areas serve as 
the collecting ground of water. These strata dip to the south and 
west and transmit through their porous structures the water which 
is to supply our wells in the northeastern portion of Iowa. As 
stated these strata outcrop or lie near the surface in the north- 
eastern corner of the state. To the west they attain their greatest 
depth, along the northern border, at about the middle of the state 
then rise rather sharply to the west and apparently become oblit- 
erated as they near the northwestern corner of the state. In the 
northeastern portion of the state these rocks can be penetrated by 
drilling a few hundred feet and there is little or nothing to case 
out save the water from the drift. As we proceed to the south 
and west, however, these sandstones become deeply over- 
laid by the later geological formations, so deeply in fact that the 
effective shutting out of undesirable waters, especially from the 
carboniferous becomes more and more difficult and finally practi- 
cally impossible. In this connection there is another consideration 
that merits attention. In the tabular statements of analytical re- 
sults given below it may be observed that as we proceed to the 
south and west we find a sharp transition from comparatively soft 
waters to very hard waters. Now, if the statements of drillers 
and city officials are to be trusted there are some deep wells in the 
areas of hard waters that are cased to the bottom. It might reason- 
ably be expected that some of them would have water only from the 
lower sandstones and that it would show as low mineral contents 
as the waters of the wells in Winneshiek County. In fact they 
never do. It seems, therefore, not impossible that there may be 
fissures sufficiently numerous and deep to allow a comparatively 
