The Portland daily press., 1865-12-13
Fifth Lecture on Geology.

Inc SUBJECT o1 frOlcSooI OuhlliiS . very III
teresting lecture on Monday evening related
to the "Glac al Period" The Professor re-
marked that he would have to speak of COM
mon place things and he would direct atten-
ton to a groupof facts. If you travel through
States south Of Maryland you find no Travelled
rocks, no boulders, no such loose, unstratified
gravel as we see spread out over the North
Through States north OF maryland, bouiders
are strewn over the surface. They nave no
kinship with the rocks below. .Ihey are
travelled. On the northern shore Oh Lake ou-
perior we End peculiar variety OF granlte
We know If no other place on the continent
where that granite was made, and yet bould-
ora Of II are found within five miles Of
Boston. -assQs daI 500 asl
The foundations of the city of Portland are
group of strata which Biologists had called
@metamorphic," mica slate, and talcose slate.
These rocks have sometimes yielded gold, and
Portland had been advised in the Maine re-
ports to explore her foundation for gold. Now
these states had been ground down and
.arge fragments carried southwark. Other
facts Of the same class were enumerated. A
gravel bed was very common place but there
are sermons on little stones as well as big ones.
Thei Professor went on to show how these
pebbles had been crushed in the same mill as
the boulders. He spoke of the ridges of gray
ell SO common in Maine and kno wn as "Horse
backs and showed that whatever force had
dispersed the boulders had piled up these
ridges. He called attention to another class
Of facts. Here and there, all over the North,
wherever boulders and gravel ridges are
found, the masses Of rock are found with their
surfaces ground down and grooved. A block
Of granite had been taken from the neighbor-
hood of Mt. Desert and put in the Natural
history rooms of Portland. The surface looks
like polished marble. There were cases as
striking as that nearer home. Near the "Great
Eastern Wharf the drift had been peeled off,
and the face of the slate polished and grooved.
The Great Eastern" had never come, but long.
before man had seen this goodly harbor,
greater than the Eastern had moved down
from the North and planned and grooved the
very foundation of Portland These planed
surfaces are fonnd high up on the mountains.
The top of Monadnock had been cut Off
Northern boulders had been lodged against
the side of Mt. Washington 5000 feet high,
and his rocks were grooved and polished to
that height. The Professor said that these
were facts enough to lift us to the level Of the
highest concentrations of science. Some
tremendous force has acted on the earth, moo
ing from the North Soathward. Before he
could discuss the nature of this force, he must
use another group of facts furnished by the
drift of northern Europe. In Siberia the
tacesof the earth was frozen to the depth OF
800 feet, and in the frozen gravel multitudes
Of primeval elephants had been found. The
rhinoceros and hippopotanaus were frozen in
he same gravel. The Professor argued that
these tropical beasts had lived in Siberia when
she climate was warm, that they had been de-
,troyedl and buried by the same force, and at
he same time, and that whatever force this
was, it was the same that made the gravel and
spread it ont. 1t must have been cold in
come form. -ao4-
The sun is drawing water from the ground
and transforming it to vapor. This vapor is
chilled and the particles build up starry crys-
tails fashioned after the pattern Of six-leaved
flowers. These frozen blossoms fall to the
earth and take. the name of "snow." The
mimic flowers (which the Professor said a
Portland lady had drawn SO admirably that her
HSnow Flake" is the finest of holiday pres
ents-can becrushed into ice. This ice we
call GLACIER ice." Now If we were to climb
The Alps, we would find point 5000 feet above
the sea, above which the snow never melte,-
The sunbeamis lifting water from the ocean,
head of the mountain. IF the snow stayed
there every, cycle of thousand years would
add a mile to the heightsof the mountain. A
time would come when all the oceans and
fakes would be lifted from their beds and piled
up in vast mountains of snow. The wheels
dread Of the nountaineer, is minister of
mercy. Tits the pivot on which the vast ma
chinery of nature plays The Professor show
ed how the snow-slides form glacier and
how the glacier tears the rocks over which it
flows into gravel and spreads il out in ridges
how it planes down and scratches the rock,
and how it transports the boulders He then
showed land our space will not allow us to fol-
low him in detail) how all the facts which he
had, enumerated would spell out the fact that
vast sheet of glaciel ice had moved down
over North America and left Katahdin and
Washington the only points of dry land in
New England-two little islands in sea of ice