Mower County transcript. [volume] (Lansing, Minn.) 1868-1915, 1873-07-10

AUSTIN, MOWER COZ
THE FORMATION or ICEHEH(:S.
Dr.: Il"y..'~ !c~rrtl',t",, Ut 'ns i'r"ccss-
A Cool Subject for Warm Weather.
A great frozen flood is pouring down
tho east and west slopes of the Green
land continent, and, as i'll the Alps,
what is gained in height Ivy one years
freezing is lost by tho downward flow
Of the mobile mass. And this move
mcnt is not embarrassed 10y any
obstacles. The lower chains Of hills do
not arrest it, for it moul,ls itself to their
form, sweeps through every opening
between them, Or OvcrtODs them. Val
lcys 10 not interfere with its onward
march, tor the frozen stream enters
them, and levels tllcm with the high
est hills. 1t hcc.ls not tho prccipic
for it leaps over it into tho plain below
"A giant frozen waterfall. Winter
and summer arc to it alike the same.
1t moves ever forward in its ir-
rcsistble career-a vast, frozen tide,
swelling to the ocean. It pours through
every outlet Of the coast ranges, down
every ravine and valley, overriding
every impeachment, grinding and crush
ing over the rocks and at length it
comes upon the sea. But here it does
not stop. Pushing back the water, it
makes it's own coast-line. and, moving
still onward, accommodating itself to
every inequality III tho bed of the sea,
rs it has before done to the surface of
the land, filling up the wide bay or
ford, expanding where it expands, mar
rowing where it narrows, swallowing
up the islands in its slow and steady
course, it finally reaches many miles be-
yond the original shore line.
Aud now it has attained the climax
of its progress. When, long ages ago,
after pouring over the sloping land, it
finally reached the coast, and looked
down the bay which it was ultimately
to fill mp, its face was many hundreds
of feet high. Gradually it sank below
the line of the waters "a it moved on.
ward, and finally it's front has almost
wholly disappeared.
A block of fresh-water ice floating in
sea- water rises above the surface to the
extent of One-eight of its weight and
bulk; seven-cights of it are below tho
surface. Tho cause Of this is too well
known to need more than a passing
explanation. Every sshool-boy is
aware that water, in the act of freezing,
expands, and that in the crystal con.
dition water occupies about one-tenth
more space than when in fluid state
and hence when ice floats in the fresh
water from which it was formed, one.
tenth of it is exposed above, while the
remaining nine-tenths are beneath the
surface. When this same fresh-water
ice which, it will be remembered, is
the composition of the glacier, is
thrown into the sea, the proportion OF
that above to that below being
changed from one and nine to one and
seven, is duo to tho greater density OF
the sea water, caused 10y the salt which
it holds in solution. Now it will be OBJ
vious that, as the glacier continues to
press further and further into the sea,
the natural equilibrium of the ice
must ultimately become disturbed
that in the end of the glacier is forced
further down into the water than it
would he if it were free from restraint,
and ut liberty to float according ~
the properties acquired by congelation.
The moment that more than seven
eights Of its front are below the water
line, the glacier will, like an apple
pressed down by the hand in u pail OF
water, have IL tendency to rise until
it receives it's natural equilibrium.
Now it will he remembered that the
glacier is long stream of ice, many
miles in extent, and although the end
may have this tendency to rise, yet il
is, for time held down firmly by the
continuity of the whole mass.
At length, however, us the end of the
glacier bur1es itself more and more in
the water, the tendency to rise becomes
stronger and stronger, and finally the
force thus generated is sufficient tC
break off a fragment, which, once free
is buoyel up to the level that is natural
to it. This fragment may be solid
cube half mile through, or even OF
much greater dimensions. This dis
ruption is attended with a great dis
trrbance of the waters, and with VIC
lent sounds, which may be heard fol
many miles but floating now free in
the water, the oscillations which tho
sudden change impaired to it gradually
snbside; and after acquiring its natural
equilibrium the crystal mass drifts
slowly out to sea with the current and
is called an iceberg.
And thus the glacier has filled its
part in the great law of circulation and
change.
! The dew-drop, distilled upon the
tropic palm-leaf, falling to the earth,
has reappeared in the gurgling spring
OF the primeval forest, has flown Will
the 1ivulet to the river, and with the
river to the ocean, has then vanished
into the air, and waited northward by
the unseen wind, has fallen rs q downy
snowflake upon the lofty mountain,
where, penetrated by solar ray, il
has become again a little globule Of
water, and the chilly wind, following
the sun, has converted this globult
into a crystal, and the crystal takes ul
its wandering couse again, seeking the
ocean.
But where tho movement was once
rapid it is now slow; where it tn en-
flowed with the river miles in an hour,
it will now flow with the glacier moi
more in centuries; and where it once
entered calmly into the sea, it will now
join the world Of waters in the midst
of violent convulsion.
We have thus seen that the iceberg
is the discharge Of the Arctic river
that the Arctic river is the glacier, and
that the glacier is tho accumulation OF
the frozen vapors Of the air. We have
watched this river moving Oh its slow
and steady course from the distant
hills, until it has at length reached the
sea ; and we have seen tho sea tear
from the slothful stream monstrous
fragment, and takc' back to itself its
own again. Freed from the shackles
which it has borne in silence through
unnumbered centuries, this newborn
child OF the ocean ruslles with wild
bound into the arms OF the parent
water, where it is carcsscd by the surf
and nursed into life again, and the
crystal drops receive their long lost
freedom, and fly away Oh the laughing
waves to catch once more the sunbeam
and to run against their course through,
the long cycle of the ages.
And the iceberg has more significance
than tho great food which the glacicr's
southern sister, tho broad Amazon,
pours into the ocean from the slopes
of the Andes and the mountains of
Brazil. Solemn, stately, and deep, III
tempest and in calm, it rides the deep.