State Convention—The Soil of Wisconsin. 355 
soil, as in basins or depressions, they hold the waters as permanent;- 
ly as if the clay-surface was a metallic bottom, without aleak, thus 
subjecting the superincumbent porous mass to the condition of an 
over-saturated sponge during one part of the season, and to the 
vicissitudes of drought at another. The rain-falls are kept too near 
the surface, and do not penetrate deeply enough to form reliable 
reservoirs, so that the roots of plants are liable to either suffer from 
excessive saturation, or the reverse, when evaporation is rapid or 
long continued. 
Under favorable climatic conditions, these soils are rich and pro¬ 
ductive, but taking the average of a series of years, are likely to 
prove less so than the drift districts. Clays, not the product of the 
drift, are usually created by local decomposition of the rock-strata, 
and contain few if any other chemical elements. The drift-clays, 
however often removed or modified, cover a much wider range of 
mineral matter, as a rule. 
The third geological division comprises the sandy, and often poorer 
soils of the State, which are mainly in its central and northern 
parts. Originally the limestones now found outcropping along the 
lower Wisconsin .River, may, and probably did, extend much fur¬ 
ther northward. But the proof of this, except as a theoretical 
speculation, may be said to have wholly disappeared in the interior. 
The district is absolutely free of limestone and of soil into the 
composition of which that material enters. It is also destitute, or 
nearly so, of remains of the modified drift, and it seems probable 
that glacial action did not progress much beyond the head-waters 
of the rivers now flowing westward from the central axis of the 
State. But if this region ever was covered by clay-deposits, the 
whole has been subsequently removed,and now presents wide patches 
of barrens, covered by a dwarfed and stunted vegetation. It is not 
a very promising agricultural field now, but yet, in the light of ad¬ 
vancing science, it would be premature to pronounce sentence of 
worthlessness on what may yet prove, for some classes of crops, the 
most productive soil in the State. 
Advancing northward, the sand}'-surface deposit is found to grow 
coarser, and, as a soil, less promising than further south. Areas, 
embracing whole townships, are found so covered with boulders as 
to completely conceal what lies beneath. Yet these localities are 
generally overgrown with heavy timber. Decomposed trap and 
