Savannah courier. (Savannah, Tenn.) 1885-1979, 1892-05-19
TREASURES FROM THE ROCKS,
Remarkable Curlosities at the Geological
Survey-How Mountains Are Made.

Remarkable Curlosities at the Geological
Survey-How Mountains Are Made.
Two very remarkable clrriosities are
placed side by side ona little shelfat the
geological survey. One is lump Of
chalcedony as big as childs fist, white
and translucent 1t is but thin shell,
and when held to the light is seen to be
nearly filled with water, which flows
about as the object is turned this way
and that. What makes 1t interesting
is that the water has undoubtedly been
inclosed and hermetically sealed in this
natural receptacle for thousands and
thousands of years. Probably it was
there long before Moses was born, and
yet not drop of IL has evaborated.
Originally there was cavity in
the rock, formed by volcanic bub'
BILE. Water percolated into it, bringing
in solution silex, which was deposited
on the walls of the little hollow in
coating of chalcedony. At length it
would have been filed up solid with
beautiful crystals, forming one of those
RtONCN, dS lilNN ulC NaiiNbs NbiNi oiN
natures treasure caskets, found con-
cealed in rocky formations where least
expected, and revealing wonders of
brilliant color. Agates are made in the
same fashion. However, in this in
stance the small channel by which the
water flowed in and odt became closed
up in some way and so the process
stopped. After the lapse of no one can
tell how many centuries the stony mass
containing the chalcedony chamber
with its liquid contents was broken open
and it fell out, being loose.
The other curious object above re.
ferred to is what appears to be petri.
fed oyster, cut through so that one sees
it apparently on the half-shcll, just as
| it would look when opened fresh for o
customer. 1t was found in challz-beds
formed largely of the shells of various
bivalvcs, probably many oysters anC
clans among them. The so-called
"heart of the animal, which is its big
wonderfully distinct There is even q
small pearl in it seemingly. Yet it is
not an oyster at all, but merely one OF
those marvellous limitations which ma
ture makes of her own works in freak
ish moods.
The government rock sharps fine
many surprising curiosity among the
rocks which it is their business to inves
tigate. Just now at the Office of the
geological survey they are engaged IN
building imitation mountains for the
purpose of studying the way in which
the eternal hills were formed by the
crumpling due to the contraction of the
earth's crust. The coal basins and Other
valuable mineral deposits in many parts
of the United States have undergone
just such crumpiing, so that it will b,
profitable to ascertain the laws govern
ing it.
These imitation mountains are bull
of wax, hardened or softencd by mixing
it with othersubstances, so that it shal
resemble in consistency the brittle rock
near the surface of the earth or th,
plastic rocks which are in that condi
tion because of the great pressure tina
exists even at depths of only two o.
three miles, as the case may be. TIL,
mixture is cast in layers of giver
thickness by melting and flowing it il
a wooden trough. When each layer ha
hardened it is taken out and Il nun
Der of the layers thus made are super
imposed one upon the other, like layer
of jelly cake, representing geological
strata. The next process is to plac,
the layers in a machine, piling shot OF
top of them to represent the force o
gravity, after which pressure is applied
from the ends very slowly by piston
advanced with screw. This cause
them to crumple up, and under tn
artificial contraction they are found t,
take precisely the forms of mountain
ranges like the Alleghenies.-Wa Washing
ton Star,