The Montgomery advertiser., 1902-10-31
GLACIERS OF THE WORLD.
Enormous Areas That are Covered
by These Great Ice Rivers.
New York Sun.

For the last five years physical geographers
have been giving a great deal of attention to
the study of glaciers One question that has
interested them very much is whether since
the beginning of the historic period the gla-
ciers of the world have augmented dimin-
ished in No perfectly definite informa-
ton with regard to this question has been OBJ
tanned. though general conclusions have
ben reached. 1t is traditional in the Alps.
however, and some other regions that valleys
now occupied bl glaciers formerly pas
ture lanrs. On the whole. it is certain that
for several centuries till quite recently there
was gradual increase in the area of glacia-
ton.
Glaciers everywhere are in a state of con-
tinual movement-they constantly incras-
ing in length or shorteping Climatic varia-
tions are. of course, the cause of these oscil-
lations. though the influence of climate upon
glacial movements is not yet fully understood
When the laws governing the movements of
glaciers are well known the science of meteor
ology will be considerably further advanced
than 1t is today There is good evidence to
snow that in the Arctic regions in the eight
zenith century and in part of the nineteenth
an important extension of glaciers occurred.
In Sptzbergen, for example. harbors which
whalers had often visited in the seventeenth
and early in the eighteenth centuries were
filled later with glaciers. that they could
longer be used by shipping. The advance
of glaciers in Iceland is said TO have covered
places that had formerly been the sites of
farms and churches. Glaciers seem. within the
historic period. to have attained their great
est extent about $50. Since that time few of
them have grown to important degree.
Many OF them have diminished in size ana
others have entirely disappeared. This phe-
nomenon has been observed In all parts of
the world.
Probably few persons imagine that glaciers
cover large area they do The land
surfaces which today buried under glacial
snow and ice are supposed to be about 4, 485,-
600 square miles in extent more than one
and half times as large the United States.
This enormous mass of ice is distributed very
unevenly over the world and nearly all of it is
in the polar regions. Outside of the perpet-
ually frozen north and south only about 49,
500 square miles of surface covered with
glaciers.
1t will he interesting to remember that there
two distinct type of glacial phenomena
the Alpine and the polar One of the best ex-
amples of the Alpine type of glacier is seen
in the Mer De Glace at Cramounix. A circle
OF peaks surrounds a depression which is filled
by compacted snow and ice known neve
This is the reservoir the source of the ga-
cier In this depression of the snow, either
falling from the heavens brought by winds
and avalanches. accumulates to great depth
is transformed into neve and begins to over
flow down the mountain side true glacier
1t is thus that the characteristic feature
of Alpine glaciers is that they occupy depres-
sions in relation to the surrounding topography
On the other hand. the polar glacier, instead
Of being formed into a depression, occupies
a eliminating position above everything else
1t is an enormous cap or cupoa rising above
the surrounding lands; IL is the dominant
feature far and wide. Such. for example, is
the great ice cape of Greenland and it is
thought probable that enormously thick
sheet Of ice may cover a continental mass Of
land in the Antarctic regions and form the
largest sheet OF ice in the world.