486 WISCONSIN STATE AGRICULTURAL SOCIETY. 
duty, and each bent on its prey, and the air so full of them that it was,with 
some degree of difficulty that a man could see through them, even if he could 
keep his head steady long enough to make an estimate; but I think I am not 
very far out of the way. Like the other mounds, it is covered with small 
trees and brush, with pieces of the ore, large and small, scattered all over the 
surface, and partly buried in the soil. The ore in its normal condition, that 
is, where it has not been disturbed by surface agencies, is everywhere con¬ 
cealed beneath the soil and fragments of ore, and, without making consider¬ 
able excavations, it is impossible to tell what portion of the mound is ore, or 
whether it is made up entirely of this material. Like the last mound referred 
to, it rises from a level, sandy plain, without any exposure of the rock that I 
could find with which it is connected. In fact, the whole country here, away 
from the rivers, is covered with sand, hiding entirely the azoic rocks with 
which the ore is, in all probability, connected. Owing to this fact, I made no 
systematic survey of this belt to the east of this place, except along the valleys 
of the Yellow and Wisconsin rivers, consequently, there may be other de¬ 
posits similar to this, rising through the sand and sandstone between those 
streams. 
It will be seen, from the descriptions given, that there is in the region of 
Black River Falls an extensive district within which we find not only strong 
indications of iron ore, but quite a number of actual deposits of greater or 
less value. And now, with railroads converging to this point, in the midst 
of a timbered country, with unlimited water power and other natural advan¬ 
tages, it requires but an ordinary amount of common sense to see that this is 
one of those places in our state where, sooner or later, important mining and 
manufacturing interests must spring up. 
The region of country on Yellow river, east from Black river, near the 
Falls, is exceedingly flat and marshy, and this schistose or slaty rock with 
which the iron ore on Black river is connected, is but poorly exposed; and, 
where exposed at all, is only along the river bank, and often only in the river 
bed. Thus, while it is sufficient to prove that this class of rock rises along 
an east and west line, it gives but a small chance to study its metalliferous 
or structural character. Nevertheless, it is not difficult, even here, by close 
observation, to recognize the fact that you are in a mineral region, or what 
perhaps would express it better, on a mineral region, for the mineral stratum 
is mostly beneath this marshy, sandy surface. 
In many places, this loose sand is very much impregnated with iron, form¬ 
ing a very lean, sandy iron ore, the iron acting only as cement to hold the 
quartz sand together. In other places, the iron ore is formed in fine grains, 
like shot, and from that up to the size of peas, or even hazlenuts, but mixed 
with the sand. The marshes also present belts of a brown, sometimes a 
yellowish grass turf or peat, very much stained with the oxide of iron. 
Where the Necedah road crosses Cranberry creek, these features are well 
developed. 
Near the center of this granitic belt, and not far from where the kaolin 
beds are noticed, there are small seams cf a very pure hematite, and also of 
