Dodgeville chronicle. [volume] (Dodgeville, Wis.) 1862-current, 1871-08-25
MINING DEPARTMENT.

Surface deposits-we have said in other
articles-are the work Of atmospheric agen
cies. or physical forces acting from above.
1t may be well enough for us to pause here,
on the threshold of our Investigations, and
explain what we mean by such agencies,
and such forces.
In the loosely, aggregate, rounded, ma
terial in which these deposits are found,
and beneath which they lie, we notice very
distinctly the action of water as the i'm
mediate cause.
If we trace it's operation, we shall find
that in the first place it falls in the form
of rain or snow. As water, it enters every
crack or assure open to the surface, and
even penetrates the pores of the rock. By
it's solvent power it attacks at once the
cement by which the particles composing
the rock are held togeather, and disinte-
grafton follows. Winter comes, and an.
other form of its power is developed the
temperature falling below freezing point
becomes ice In assuming the form tex
pands, and in expanding it not only sep
rates particle from particle, but masses
from the mountain sides. Spring comes,
and it returns to water and IN assuming
this form, it contracts, leaving the rock in
which it had been held as ice, in loose
friable condition. Now follows the rains,
floods and torrants, of spring summer and
autumn, and this disintegrated, friable fra
gmentary material, is carried by these
forces from higher to lower levels, from
the hill and mountain sides to the valleys
beneath where it is redeposited, as water
only can redeposit such material.
Here we have before US in their simple
forms, the chemical and mechanical pow
ers Of water, acting as physical forces, or
atmospheric agencies in producing what
we call surface deposits. But this is but
one aspect of the forces we call atmospheric,
or | might say, one link in the chain of
forces that operate the surface of the
earth through the atmosphere as their me-
dunn.
Water here seems to be the immediate
cause of this phenomena ; but closer cx-
animation will show US that it is after all,
only modified form Of power or force,
the source of which lies beyond it. We
notice it is true, its direct solvent power
on the rocks. We notice also its power
in the mountain stream, and in the river
currant, carrying down often with vio-
lence, sand ground, and even rocks. But
i when we gaze on the effects thus produced
and-ask whence comes the power of the
mountain stream, and the river current,
bearing those material into the valleys, and
even into the sea ? the answer is--the
GraUitati0n of water in the course which
the stream, and current dirans. Ii we ask
how came the water to be IN that poSit-
ion, whence itfell as rainthe answer is-the
vapor from which it was condensed was
drifted there by the force of the winds.
Il we ask-how came this vapor to be at that
elevation the answer sit was traised
by the foerc of evaporation if we ask what
is the force of evaporation the answer is
the heat of the sun.
Here then, through these varied forms
OF physical force, we reach their source,
the ultimate cause that produced them.
And if we examine this subject further, we
shall find, that not only these, but all other
forms of physical force operating on the
surface of the earth, can be traced back
directly, or indirectly to the suns heat as
their cause. The point l wish to make
plain, and guard here, is this: All natural
phenomena flow to US from a few general
laws, or centers of force. And in our in
vestigations it will not be safe to rest our
conclusions on any form Of force, which
they generate, unless it be as a guide back
to the cause that generated them.
Without stopping to inquire how ma,ly
general laws, or centers of force there may
be underlying natural phenomena, it will
be sufficient for our purpose to know tina.
there are two. And to one or the other of
these, we shall have to trace back, as to the
primary cause, the most of the phcnomcna
that will come under our observation in
connection with mineral veins, and ore de-
posits.
These are the two great sources ofnatur
heat, consequently the two great centers
of physical force. One is found in the sun,
the other in the center of the earth. From
one comes to US all the physical conditions,
and physical forces found on the sur face
of the earth in connection with organic
nature from the other, all the changes
and notifications; all the physical con-
ditions, and physical forces that we find in
the crust of the earth, in connection with
mineral formations.
These two sources of heat and centers
70 force, we must hold apart. The forces
they generate, and the phenomena they
produce, we must study as to separate,
and distinct classes. In this way, and
only in this way, shall we be able to dis
tinguish the products of nature produced
by physical forces acting from above, and
those acting from below.
Like the naturalist on the boundary
line of the animal and vegetable kingdoms,
where their forces meet, land their pheomena
mingle we stand now on the line between
these two centers of physical force, where
the products Of the one par take more
or less of the characteristics of the other.
And we shall find it little difficult while
here, to distinguish between them. But
ia leaving surface deposits, to extend our
Investigations into the crust of the earth,
we shall leave behind us that class of phe-
nomena produced by forces acting from
above, and follow only that class of pheno
mena produced by forces acting from below.
Forms of force, then; as we'll as forms Of
matter must receive our closest attention
in the investigation Of the lead district.
j. NJ.
Mazomanie. August 25 1871