Omaha daily bee., 1906-07-29
INCREASING USES FOR MICA
Once seen Chiefly In the StOne-NONS
Employed to InsuIate Elec-
trio wires

There was a time when mica, or isinglass
as Il was far more commonly called, was
familiar In one limited use in every house
hold in which there was a parlor or sit
ting room stove, thin, transparent sheets
Of this mineral being set in the stove door
Through the "isinglass,' not destruct!bie
when subjected to heat, glass would
have been. the glow Of the FIRE within could
be seen
With long use the mica might become
smoked up and Opaque, or II might become
marred and broken. Then the head OF the
household would get and set into the stove
door fresh isinglass from the stove dealers,
while the fragments OF the old were very
probably turned over to the children. who
were likely to be surprised to find into how
much thinner sheets still the thin old pieces
from the stove door could he divided. As
matter of fact, mica is Invisible into sheets
one two-thousandth of an inch in thick
ness.
Now there are many who don't know
mica at all, not even as Il is used on stoves,
people born and raised in houses that are
heated by steam, in which no stoves are
used for heating purposes; but while the
number OF these is large and all the time
growing. the number OF people who yet
use stoves is larger still; and so while mica
may have passed entirely out OF the sight
and mind of many who once knew IL in
this use. and in this use only, the prepara-
ton OF It for stove use still constitutes a
regular branch of the mica trade; and thus
one of the old uses Of mica still continues.
The chief use to which mica is now put
is one not dreamed of until within COM
parativey few years, namely, as an in
sulating material in the construction OF
electrical apparatus, for which purpose its
use is now general and constantly increas-
ing and far larger than in any use to
which it had ever before been put.
Mica is now used also for making Chin
neys for incandescent gas lamps placed
where they would be exposed to drafts. or
out of doors, subject to the weather. Mica
is used to make protectors for ornamental
candle shades, and 1t is used for making
fancy boxes, and, in place Of glass, for COW
ering the labels on drawers, as in desk.
Ground up mica is now used in the manu-
facture OF lubricants and OF fertilizers, and
Of dynamite, and in other forms II is used
for boiler coverings.
Mica was long used for windows and for
lanterns, and IT is still used in lanterns
where such use would be advantageous. II
Is used in place Of glass In spectacles worn
by stone ana metal WOIheIss anu III IllllefS
lamps, and il has been in the past or still
is put to various other. including orna-
mental, uses; but among its various mod
ern uses the chief is in It's application to
electrical machinery. For this the mica is
cut into hundreds OF different shapes aud
sizes.
India is the chief source of the world
supply OF mica, with Canada next, the
United States next and Brazil and other
countries following. Mica from one source
and another ranges In color from white or
transparent, through various shades to
black
In the formations In which IL exists It is
found in more or less scattering deposits,
or in pockets. It's value depends, with re-
gard to the uses TO which IL may be put
on its color, its freedom from impurities
and the size of the sheets that can be OBJ
tanned from it.
Now this anciently known mineral for
many years put to varied though COM
paTatively limited uses, finds more extern
sive use than ever in applications pecu-
lisrly modern.-New York Sun.