The Florida agriculturist. [volume] (DeLand, Fla.) 1878-1911, 1883-01-17

| try on guard. all carved lrOm IniS
same marvellous sfrozen water"
And now few words in conclu-
sion concerning those wonderful ice
mountains called glaciers.
| The first adventurous mortals who
ventured to advance their opinions
that glaciers were not the immovable
masses they were supposed to be,
but in reality were capable OF moves
meut, and dii move with constant
though almost imperceptible move
ment, were laughed to scorn.
What those immense mountains
Gus seas of ice move? flow down.
words like rivers The idea was
naly worthy of lnadmen
But nevertheless, the subject once
preached, biologists began to watch,
and then to doubt, and by and bye
it was seen that little stone hut,
which was built on the side OF the
Lower Aar glacier, in the upper Alps,
had decidedly changed its positions;
it was nearer TO the houses in the
valley than when it was built, and
certainly no one had picked up that
stone hut and carried it down the
| glacier
1t was a great mystery, but there
was one illustrious man who had
nerve enough, and courage enough
to determine to solve 1t.
The great Agasslz shut himself out
from the world for two years, living
in little hut on the glacier, shelters
ed from the storms by fragment OF
rock, content to suffer cold and pri
walton, if, as his reward, he might
penetrate this strange secret of ma
ture.
And he succeeded; by patient and
ingenious experiments and measure.
ments, he found that the little stone
hut above alluded TO, had moved il
thirteen years, four thousand nine
and forty feet, showing that the gla
cier on which it rested had an annual
forward and downward movement,
OF three hundred and eighty feet.
! Yes, it was indeed true that gla-
ciers moved. The fact became es>
tablished, and its supporters trium>
plant; but how? by what means?
The mystery, too, soon came to be
! solved. 4 is well known that the
freezing point of water, OF The meIt-
ing point of ice, is lowered by press
sure, and in this fact we have the ex-
PLANTATION OF the movement OF gla-
eiers.
These great masses of ice are nat
urally full of cracks and assures, and
some portions ale exposed to great
er strain than Others
The pressure thus exerted CORE
spends to melting point very much
below the temperature of the whole
mass, aud so, just at these points o!
pressure, the ice melts, the strain is
uplifted, and for an instant the mass
is free to move forward like a fluid;
almost directly, however, the pres
sure being removed, the water freezes
again, and the motion at that point
is arrested, but only to be renewed
at some other.
And this is the phenomena Of
melting and freezing which is going
on all the time, all over the glacier,
causing the strange spectacle of an
immense mass OF rugged, solid ice
creeping down over its rocky bed
like a sluggish stream OF tar or syrup,
Who can wonder that the statement
of such marvel was at first received
with Gerision and scorn?
But now that it is a proven fact
much that was before mysterious in
the formation of our earth's surface
marks is cleared away.
Not SO many years ago. had ge-
ologist been asked, "To what power
does the United States owe its great
northern lakes?" the answer would
have been, ITO the power of the ter
rible upheavals which once convulsed
the earth" But ask the same ques.
ton now, and the answer would be
different-"It owes them to the pow
er OF ICE!''
For this is what Agassiz, the king
| of scientists has shown us; that in
ages long gone by, immense masses
OF glacier ice moved with slow, but
irresistible majesty over the face OF
the earth, leveling mountains and
digging great pits III its surface; pow.
dering, grinding, excavatlng, raising
up and throwing down, the fearful
mass moved on, doing It's appointed
work well and thoroughly, and final
ly passed away, leaving scarce any
other trace behind it, save lofty noun
tains piled up and vast inland seas