Evening star., 1896-01-11

10 ne IOunQ great Oc-
posits Of mineral rubbeT-enough to make
gum shoes for large part of the popuia-
ton of the United States. piece OF this
substance about eight inches square and an
inch thick was lying on his desk recently.
1t was black and it looked and felt exactly
like ordinary rubber.
"You see, 1t is quite elastic" said Mr.
Eldridge, in course of a conversation with
writer for The Star, bending 1t with his
fingers. There is no telling how many val
liable uses it may be put to in the future,
But 1 imagine that it will be employed
largely mixed with the vegetable rubber OF
commerce For roofing material 1t has
already been proved excellent. In the min
ing towns Of Utah mineral rubber Is util-
lied commonly for roofing, being prepared
in sheets consisting of layer OF burlap
with the rubber on both sides. Nothing
could be more thoroughly waterproof. Be
cause 1t Is so new, not much is known
about this peculiar stuff and its possibiii-
ties Only few tons of it have been mined
near the Ui1 tab reservation, where 1t is
chiefly found. 1t occurs in veins. but the
number and size of the latter are not re-
liably known as yet.
Mr. Eldridge took up from his desk
qreer-looking. black:sh chunk OF som ethng
1t was somewhat soft to the feel.
THAT is another unexplored mineral,
said he, in explanation. Very little is
krown about it yet. 1t is called mineral
wax. In parts of Utah it is found in veins
Ike the mineral rubber. Its scientific name
is 'oZokerite.' The mineral rubber we know
as elaterte.' Sometimes the ozokerite oc-
ours in pockets between layers OF shale
1t has not been mined at ALL Many uses
for it are likely to be discovered in the
future. To electricians 1t will be valuable
doubtless. inasmuch as it is one of the best
insulating materials for employment in
their business. But here is another inter-
esting mineral substance from the same
state. What should you take 1t to be?'
Deposits Of Gum Asphalt.
The object referred to by Mr.. Eldridge
was about as big as his head and looked
exactly like a piece of obsidian, or black
volcanic glass. 1t was hard as any rock.
THAT is gum asphalt" said he. MY
chief business in Utah was to examine the
deposits of this material 1t is a wonder
fui substance and represents a great min
eral resource that has hardly been touched
as yet. However, it has been mined to
small extent, and two companies are at
present engaged in taking it out of the
ground 1t is nothing more nor less than
an exceedingly pure kind of asphalt and
| Its important usefulness is in the manu-
| facture OF varnshes. You must observe
| that varnishes ordinarily are given to
cracking, but not so with any varnish made
| from this stuff. Here is a sheet of tin COW
cred with such varnish. You see, l can
bend and crumple it as much as 1 choose
without a crack; the metal will break be-
fere the vdrnish. That is because the gum
asphalt is elastic
"Under what conditions is the substance
found?" inquired The Star man.
Under conditions so extraordinary that
| nobody has been able to account for them
very satisfactorily replied Mr. Eldridse.
The deposits are found chiefly within and
| in the neighborhood of the Uncompahgre
| reservation. You are walking across the
country, let us suppose. and you come upon
| a queer-looking streak that runs straight
| as an arrow flies. Perhaps the streak is
| of ribbon along the ground, over hill and
| dale, so that standing upon 1t, You can
| follow 1t with your eye for miles. This. not
| so much by reason Uf its color as because
| it makes a sort of swath through the vege-
| tation. The surface sand supports a few
| plants, but they do not grow to advantage.
You brush away the sand. and beneath it
| you find that the streak is perfectly black
1t is a vein of gum asphalt.
How the Veins Run.
| There are many such veins near the
eastern edge of Utah, and some of them
run over into Colorado. They have tend
| ency tn run parallel to each other, with
a. trend from northwest to southeast. They
vary in width from quarter of an inch to
| eighteen feet, and they are from half a
| mile to six miles in length. Nobody knows
how deep they are. 1t is believed that they
extend to depth of at least 1000 feet, so
that the quantity of material obtainable
| is enormous. The greatest depth thus far
| reached is 12o feet. Thus far mining for
| the stuff has hardly got beyond the pros
| pecting stage. The veins are perfectly YER
tical For a few feet from the surface the
| substance is more or less impure, owing to
| weathering, but lower down it is entirely
free from impurities. Digging for it is
the hardest work imaginable. owing chief
! ly to the dust. The atmosphere of the
shafts becomes literally loaded with asphalt
| dust. which is highly explosive. The body
| heat melts it, SO that it forms brown
| coat all over person exposed to it. Soap
| and water are 10 good at all for washing
| it off; the only thing that will remove it
is kerosene. A tank of kerosene is kept
| handy, so that everybody who comes out
of the mine may take bath. I can state
| from personal experience that kerosene
| baths are no. SO agreeable as the ordinary
kind but they are luxury under such con-
| ditions."
| Theory Of It's Origin.
"How did these veins Of gum asphalt
come to be formed, Mr.. Eldridge?"
"They represent cracks in the crust OF
the earth, made in a distant geologic epoch
and subsequently filled in with gum as
| phalt. The stuff has much of the appear
| ance and hardness of jet you observe
Of course, it is only useful for MAX
ing black varnishes. No, it will never be
rsed for paving streets, unless perhaps as
| an admixture with ordinary asphalt to i'm
prove the quality of the latter: it is too
| valuable, you see 1 cannot tell you from
| what source the substance was originally
| derived. 1t is believed that all asphalts
| are of vegetable origin. We know that
during the conforming period vast ac-
cumulations of vegetable material We're laid
| down in beds and became transformed in
| various ways subsequently by chemical
| processes. According to conditions govern
| ing, they We're metamorphosed into deposits
| Of coal, petroleum or bitumen-the last be-
| ing what we call asphalt.
| at is imagined that the vegetable beds
| that were changed into bitumen were laid
| down in the bottoms of rivers and lakes,
| where they were covered up by sand or
clay, and underwent decomposition while
| m oistened by water, but without contact
| with air. One spot where this occurred
vas in the neighborheod of the Dead sea,
| whence formerly great quantities of as
phalt were obtained Very little is got from
there now, the most important source of
the worlds supply being the famous Tar
lake of Trinidad This lake is filled with
bitumen instead of water, being about a
mile and q half in diameter. Its surface is
so smooth that it looks like lake of wa.
ter, and in hot weather the sun melts it to
depth of some inches. In the center OF
the lake the asphalt is boiling.
l nf