The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1885-03-08
THE GREAT ICE AGE IN INDIANA.


topography Of a country as influencing
its civilization and determining its political di
visions has been set forth by Buckle in his
'sHistory of Civilization" and by Draperin his
"Intellectual Development of Europe" 1t
was the thought of Cowper when he
wrote Glands intersected by mar
row firth abhor each other, and
mountains interposed make enemies of
those who had else been friends" Professor
Reike has written various essays showing the
effect of the geological structure on the his
tory Of the British islands. This is more APP
parent usually in mountainous regions but is
also amply illustrated in Indiana, which has
less than 800 feet variation in altitude.
Where the soil of any large area is formed by
the disintegration of the country rock, its
character and fertility will depend on the ma
ture of that rock
The limestone counties, through which the
Louisville & Chicago road passes, from Cos
port south, furnish far better soil by their
decomposition than the knob sandstones
These differences are marked in Indiana only
in the southern quarter of the State, where
the soil is formed by the decomposition of the
rock in stu rather than by the mixed accum-
ulations of the glacial drift. The exceptions
are in the cases of soil formation by the de-
post of river alluvium. That the central and
northern portions of Indiana have a soil of
such uniform and almost unrivaled fertility
is due to the occurrence of the glacial period
In geological history. A succinct and highly
interesting history of this period, OF such mo-
ment in the economic interests Of the State, is
furnished in the present report by DR.. j. w.
Newberry, the late State Geologist of Ohio.
Three fcurths of our State is covered with
asheet of clay, sand, gravel and powders from
twenty to o50 feet in thickness, concealing the
underlying rocks The southern margin Of
this drift area runs from Aurora southwest
through Ohio and Jefferson counties to JEFF
fersonville, into Kentucky; then back through
Clark, Scott, Brown and johnson to the south
line of Morgan county. 1t then bends south
west through Owen, Greene, Knox, Gibson
and Posey to New Harmony, where it crosses
the Wabash into Illinois. All of the State
north of this is covered with drift deposits,
and was once occupied by great glacier, like
the great glacier twelve thousand miles long,
six hundred wide, and thousand feet thick,
which now occupies Greenland.
The advance and retreat of this great ice
sheet required thousands Of years. The peat
beds and forest trees found between its layers
and the great secular climatic revolution
which resulted in the retreat of the icesheet
to Greenland, are ably discussed by Professor
Newberry. The drift deposits include masses of
pure copper, transported five hundred miles
from Lake Superior; granite, slate and iron,
Niagara fossils, from the Lake Huron
islands, corniferous limestone, from the
islands Of Lake Erie; crystalline
rocks from the Canadian highlands, and mag
netic iron ore from the. Laurentian series
north of Lake Ontario and the st. Lawrence.
Professor Newberry thinks that in the re-
moval and deposition of the drift, ''icebergs
took an important though only local aud
subordinate part He does not favor the
simple Lyellian hypothesis, which accounted
for the cold of the glacial age by supposing
that the lands of the arctic region were high
and continuous, so that the gulf stream could
not penetrate and warm the arctic seas. That
the glacial cold was due to the great elevation
of British America is theory now generally
discredited
While there viii probably never be perfect
unity of sentiment among biologists as to the
cause of the glacial cold, the theory now very
generally received is elaborated at great
length By Prof. Croll, of Glasgow in his in
teresting work, Climate and Time His
theory is that the variations in the eccen-
tricity Of the earth's orbit which have been
carefully calculated for millions of years, for
ward and back, have, in combination with the
procession of the equinoxes, caused regular
changes in the climate of the northern and
southern hemispheres alternately, as great as
any which geology reports, and sufficient to
account for the cold of the glacial age.
The supposition that the low temperature
was produced by the earth passing, with its
sister planets and the sun, through cold
places in the stellar universe, or that the heat
Of the sun, which now determines the surface
temperature of the earth, has been variable
throughout geological time does not comport
with any observed facts, and the burden Of