The evening telegraph. [volume] (Philadelphia [Pa.]) 1864-1918, 1867-02-13
GLACIERS IN THE TROPICS.
Lecture bv Professor AgassIz.

Lecture by Professor AgassIzs
The third in the course of scientific lectures
now being delivered at the Cooper Institute, by
Professor Louis Agassiz, came off last evening
IN the presence of a large and appreciative
audience. His subject was, ''The Ancient
Glaciers in the TroDcs.n
Previous to the Professor making his appear
ance, member of the Association for the Ad-
vancement of Science and Art read criticism,
which appeared IN one of the evening papers,
in reference to Ieserving seats Tor school
children, banishing their elders to remote por-
tions OF the hall" The gentleman made an
explanation which was received blythe audience
as satisfactory.
Or. Griscom introduced Professor Agassiz,
who proceeded to say that he omitted to state
in his last lecture that the valley OF the Anna
Zon was easily accessible, for steamers left New
York for that place once month. He also
stated that IL would be Interesting for those who
contemplated commercial relations with Brazil,
especially in the valley of the Amazon, that Rll
the spices Of the East-pepper, cloves, nutmeg,
camphOr and the like-have been cultivated
there, and might be cultivated to such advan-
tage that they could, under skilful MANAGEMENT,
share the benefits of the commerce which is
now exclusively in the hands OF European ma.
tions.
He would first call their attention to the SUM-
mits OF the Alps, and then gradually invite them
TO travel over those regions over which the
glaciers themselves moved, and perhaps they
would see that where the tropical sun shone
to-day, there was at one time field OF ice eX-
lCuuluS over Jne valley OF bu6 AmalOu 6&LeDu-
ing towards the Atlantic, and perhaps covering
the sea to such an extent that the question
might well be asked, as it was now asked at the
Polar region, Whether there was open water
under the equator? So far, he believed, did
the evidence go, and so extensive, he was salts
fed, had the changes of temperature upon the
surface Of our globe been.
What are glaciers? An accumulation OF snow
and ice gradually passing from a more snowy
condition into more icy condition, and in the
process OF this change descending from the
heights where snow falls into the region where
the snow and ice melt every summer. In their
appearance they present unusual beauty We
had no glacier regions on the eastern side of
this continent; there were glaciers in the Rocky
Mountains along the whole range of high sum-
mits, which extends to the southern extremity
OF South America, varying in height
The lecturer proceeded at length to give
description of the formation Of glaciers and the
glaciers of the Alps. Ike immence lcebergs
which were seen on the Atlantic were not frozen
sea water, but glacier ice broken loose from the
masses to which they were attached and then
hoated away. He called their attention to the
transparency OF the ice to heat, as it had an
important bearing upon his subject, and eX-
planned, by means of the blackboard, the effects
OF glaciers upon the ocean and the land. In
order to have proper idea of what glacier
was, it must be seen under all possible condi.
tions of the atmosphere.
The Professor then described peculiar phe-
nomena respecting the glacier, which would be
almost unintelliglble unless accompanied by
the geographical map which he drew on the
| blackboard. No glacier was a stationary mass
| Of ice, but a moving mass, which moved at a
given rate, which was proportionate to the bulk
of ice. He had been under glaciers and saw
pieces OF rocks indentng the ice, which fell
from the mountains. The Professor demon
strated that at one time the whole surface of
Switzerland was covered with glaciers; so of
England, and he traced marks of glaciers over
the whole of North America down to the lat-
tude of thirty-two degrees, at Charleston, South
Carolina.
From this he deduced the great fact that the
| climath of the earth had undergone stupendous
| changes. There were glaciers which moved
| upon even ground southwark, and that fact was
| now clearly established. He was satisfied that
| there were glaciers in Maine SIX thousand feet
| in thickness, and that snow fell upon this CONT
nent fifteen thousand feet thick. The earth was
| tion of ice within the tropics. In the neighbor
| hood of Rio Janeiro he saw unmistakable signs
| of former glacier action, and after visiting the
| valley of the Amazon he was satisfied that once
the whole of that valley was occupied by stupen
| dous glaciers coming down from the Andes anC
| the region of the Atlantic.
/ All the loose materials which now formed the
| bottom of the valley of the Amazon were mate
| rails which had been ground by the ice, haC
scattered evenly over the whole of that land il
the same manner as the valley of the Rhine wa
now occupied by mud and clay which were
once ground in the Alps. In conclusion, the
| Professor said that he was convinced, from his
| Investigations, that the bay of Massachusetts,
Long Island Sound and all the bays of oul
| great rivers were once filed with loose mate
| rials of this immense sheet Of ice ADVANCING
towards the ocean.-N. Y. Herald.