The Minnesota pioneer. [volume] (St. Paul, Minn. Territory) 1849-1855, 1850-05-02
COMMUNICATED.
fFor the Minnesota Pioneer

MIR. EDITOR:
l have employed leisure hour, in att
tempting to combine the parts Of the
science of Geology. SO as to convey a
clear idea Of it as whole. If il only
has the effect to cause your readers to
investigate for themselves on the SUBJ
ject it will do good.
Geology then is that science which
unfolds to us the solid substance of tho
earth.
The earth is nearly round ball-sbap-
ed like an orange: but for illustration
we will compare it to an ordinary school,
globe, imagine the center to be COM
posed of solid granite rock, and the
surface, SO far as it has been laid open
by rayines, rivers, mines, earthquakes
&c. to be composed of layers, of inter-
mixed primeval substances wrapped
around, and laid one over the other,
like the coats of an onion.
These layers are composed of miner
ais, or rocks, variously intermixed, they
are termed formations, and the first
layer on the surface is called volcanic
formations. The ''pedrigal'' or stony
Cherubusco and Contraras in Mexico
afford an example of this kind of for
nation, minerals and metals of all kinds
are found running in wedge-shaped
veins through it. Gold as now found in
California, is supposed to have been
thrown out of the craters of volcano.
/ The viens Of lead ore found about Ga
lena, is an example Of these veins, and
they may have been produced by light
ming striking into the earth, causing a
fusion Of mineral substances. The sec
ond layer is termed alIuvial formations,
and is produced by the action of rain,
river water, air sc. upon the other for
nations, and consists Of decomposed
mineral, vegetable and animal bodies,
variously intermixed, and deposited in
valleys, or elevated plains, or flat land,
between mountains and river banks.
The third layers are termed fat or
horizontal formations, and contain abun-
dance Of known animal and vegetable
remains, such as FISH, tortoise and pine
trees sc.
The fourth layers are called transit
tive formatiops, being supposed to have
been produced while the earth vas in a
state of transition, from inorganic mat
ter, to organic life. 1t is in this layer
that petrefactions first make their ap-
pearance and are confined to the low
est links in the scale of organization
such as worms, and moses, which are
extinct proving the date Of their forma-
tion TO be very remote.
In the fifth and last layer termed prin,-
Tive formations, the granite rock lying
undermost, no relic of either animal or
vegetable petrefactions are found. and
they are termed primitive from being
supposed to have been earliest produced,
or at the time when the earth emerged
from state of chaos, to state of order.
We have now got down to the granite,
and beyond that the earth has never
been penetrated, but it is supposed that
: granite rock forms its entire center or
nucleus.
The most careless observer can form
an idea Of the earth's structure, in view
ing the different layers of alluviai soil
limestone and white sand stone forming
the banks and bluffs Of the upper Mis-
sissippi river near st. Paul, the exeava-
: tions in which have as yei developed no
organic remains of animals, or veget-
ables but the strata or layer Of lime
Istone, has furnished some fine tagging
s and building stone, easily got out, with
d spade, sledge hammer. and crowbar,
g EDUCo,