The Washington herald., 1914-11-22
ASBESTOS
WRITING
PAPER
NEXT!

- ONE new uses of asbestos, generally
known as a fire and heat proof
- substance. are in filtration. refrig-
Grafton, and the manufacture of
paper Christmas trees, building material,
rope, yarn, and clothing. Many of the
finished products and samples of the raw
material are now exhibited in the Division
of Mineral Technology Of the older Unit
ed States National Museum building in
Washington.
Most of the asbestos mineral fbers
we're obtained from the large deposits of
asbestos found in the province Of On
tario. Canada, which supplies practically
the whole world This substance occurs
in veins varying in width from a small
fraction of an inch to three and four
inches. The fbers lie across the vein.
so that their length is determined by the
width of the vein, the usual width being
from L to q of an inch. The rock
containing the fiber is Quarried by sur
face methods much as is limestone.
After being blasted down. the rock is
usually hand sorted, the material con-
tanning fberS over one inch in length
being hand-cObbed, or Carded, a process
which tears the fiber from the rock. The
larger fibers are then packed into hun
dred pound sacks and shipped to tn"
market. The usual price per ton is about
$500.
The minute individual fibers of ashes
toS are not even microscopic, being finer
than any other organic or inorganic fiber
known, thus necessitating special ma-
chinery for spinning and weaving.
The hand-cObbed raw material of long
fiber is used in making asbestos gas-logs.
spun into yarn. twisted into rope used by
fire departments, and woven into fire
proof cloth for theater curtains. clothing.
etc. The theater curtain manufacturing
business alone is an enormous one, over
1000 curtains of different sizes being
made annually. The largest one of these
is that at the HippOdrome in New York.
Other theatriCal uses for asbestos ire wall
coverings and Innings. and scenery where
municipal regulations demand absolute
fire precautions. This same form il used
with rubber coating in steam fitting, for
valve and bearing packing. gaskets and
sheet packing. as well as to cover mangles
in steam laundries II enters into auto
mobile construction for general packing
and heat insulation, and as brakC-shue
lining.
All the material with fibers less than
:. inch in length goes through milling
first it is passed through a crusher which
breaks it up into inch sizes. then into
4 dryer where all the moisture is re-
moved, and over a set of screens separat-
ing the fbers into various sizes which
are again crushed and sorted. The finest
screenings with tbers less than 1-16 inch
are called asbestos sand from which wall
plaster and shingles are made. and. when
mixed with cement. building material
and mill board. The coarser material
from the screens is fed into d cylindrical
tub called a "fberizer' which beats up
the rock, tearing loose the fbers which
are drawn out at the top by means of a
suction fan. These fibers are sorted by
shaking screens. into what is known as
Mill No l and No. =: the former. being
over = inch in length, sell at 500 tho
ton. while the latter, the smaller. sell for
about $50 the ton.
Milled material is used in the manu-
facture of paper. mats for stoves. and
other kitchen utensils; heat insulating
materials such as pipe covering. boiler
plate and firebrick; building materials
including roofing boards and shingles.
laths, plaster and paint; besides gloves.
clothing for firemen, and socks said TO be
very cheap and practically indeStTuctible.
One firm is trying to make writing paper
but SO far has not succeeded on account
of the blOtter-like absorption of the
paper, and the fact that while the paper
does not burn, the inscriptions in ink
or pencil disappear at a red heat. With
the perfection of this phase OF paper
making, future generations will hp en-
abled to preserve manuscripts without
fireproOf safes and vaults.