The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1898-08-14

white posts at the corners of the different
properties. Outside of these there are no
marks There is not enough waste wood IN
the whole desert to make q line fence about
a city lot. There is not a blade of grass,
and, with the exception of here and there
scrubby tree, all is bare, gray. desolate
sand. with here and there a CLINT of white
where the salt rock has caught the rays Of
the SUM- There are few more barren places
in the world than the Chilean desert. The
coasts of the upper part of the country are
as bleak as the most barren parts of the
Rocky mountains, and this sand and rock
extend inland almost to the tops of the
Andes. Along the coast there is a low range
of foothills rising in places to the height of
a mile and more above the sea. Beyond
this there is a rolling valley, which runs
from north to south, and on the other side
of this valley the foothills of the Andes
begin. 1t is along the western edge of this
valley that the nitrate is found In some
places it is not more than fifteen miles and
in others as far as ninety miles from the
sea, but the deposits all lie along the west
ern edge of the valley, forming strip Of
an average width of about mile and run
ming irregularly, as / have said, from north
to south for distance of more than three
hundred miles. In some places the deposit
is four miles wide, and in others it plays
out altogether and crops out some distance
farther on. In some fields the nitrate rock
lies on the top of the ground. In others it
is found from thirty to forty feet below the
surface, with a strata of salt rock on top Of
it. The nitrate itself is seldom found pure
in nature, though much of the rock con-
tains from 40 to 60 per cent. Of nitrate The
AntofagaSta rock does not contain more
than IA per cent. of nitrate, and other fields
vary with the nature of the deposit. 1t is
getting the nitrate rock out of the earth
and extracting the pure nitrate salts
from it that constitutes the immense indus
try of the pampas or nitrate fields. AS to
where the nitrate comes from there are a
number of theories One is that the desert
was once the bed of an inland sea and that
the nitrate came from the decaying of the
heterogeneous sea weed Another theory is
that the ammonia rising from the vast beds
of guano on the islands off the coast was
carried by the winds over the range of hills
near the sea and there condensed, settled
and united with other chemicals of the soil
to form the deposits, and still third is that
the electrical discharges of the Andes COM
bine with the elements of the air to make
nitric acid This acid was carried down
through the ages in the floods of the Andes
and was deposited these beds in the
form of nitrate of soda. None of these
theories are entirely satisfactory and
yet no one has absolutely solved the problem
as to whence the nitrate comes.
HOW NITRATE IS MINED.
We shall see how nitrate is mined by a
visit to the great pampa of Tamrugal.
This pampa or field has sixty miles of
oficinas and nitrate fields. A railroad has
been built through it to carry the nitrate
to the seacoast at Iquique, and on it have
grown up vast factories, towns of CORFU
gated iron huts, in which the tens of thou
sands of workmen employed in the bust
ness live and the homes of the scores of
vell-educated Europeans who live here and
manage the properties. Leaving Iquique
the railroad carries you up the hills and
brings you right into the nitrate fields.
You are soon in plain about twenty miles
wide, with low hills rising upward on the
right and left. On the side of this plain
nearest the sea the earth looks as
though it had been plowed by giants. and
it lies in mammoth clods of all shapes and
sizes. These are the nitrate fields which
have been or are being worked. The rest
of the land is bleak, bare sand. There is
no vegetation and no sign of life of any
cods, nitrate rock, which is called caliche.
1t is q soluble rock of different colors. In
some places it is almost white and looks
like rock salt. In others it is yellow, and
in others all shades of gray lemon. violet
and green. The strata of nitrate usually
lies two feet or more under the earth. and
there is often salt rock or conglomerate
above it. The method of getting it out is
to bore round hole about a foot in diam
eter through the upper crust and to eX-
tend it down for a few inches into the
soft earth below it, Now, into this hole a.
boy is let down. He scoops out a pocket
for the blasting powder and arranges the
fuse. He is then pulled out and the fuse
is lighted An explosion follows. A great
yellow cloud of smoke and dust goes up
into the air and the earth Is broken up
for a radius of about thirty feet about
the hole. The nitrate rock is now dug off
with picks and crowbars. 1t is broken into
pieces of thirty pounds or less and is load
ed upon iron carts to be taken to the fac
tory Each of these carts will hold three
tons Of rock and each is hauled by three
mules, the driver sitting upon one of the
animals.
AT THE FACTORY.
The caliche or nitrate rock is taken in
these carts from the fields to the oficina or
factory. This usually stands in the midst
of the fields. 1t is a collection of buildings
with great smoke stacks rising above them
1t contains thousands of dollars worth of
costly machinery, vast tanks for boiling
the nitrate rock, crushers like those of q
smelter to break it to pieces and settling
watts in which the liquor containing the pure
nitrate of soda is left until it has dropped
it's burden of valuable salt The nitrate
rock Of the Aqua Santa fields as we saw 1t
blasted out of the earth has only about 40
per cent. of nitrate of soda in it. The nj
trate sent to the markets is from SO to So
per cent. pure, and the rock must be so
treated as to bring about this result. This
is done by boiling the rock just so much
and no more. The crushers reduce the
caliche to pieces about two inches thick and
il is then taken to the boiling tanks which
are situated in building perhaps fifty feet
above the ground. These tanks are each
big enough to form a bath tub for an ele-
plant. They are twenty-four feet long,
nine feet wide and eight feet deep. In them
there are coils of pipe into which steam is
running, raising the temperature Of the fluid
in the tank to any desired point The cali
che is carried in cars up an inclined railway
and dumped into the tanks. Then water is
admitted and is allowed to flow from tank
L iy,c TO he