Catoctin clarion. [volume] (Mechanicstown, Md.) 1871-1940, 1912-10-10
THURSDAY, OCTOBER 10, 1912
TUNGSTEN AND ITS USES.
An Unusual and Important Mineral
EMPLOYED in Various Industries.

Last year there was sharp de-
crease in the production of tungsten
ore owing to the decrease in the de-
mand for tool steels, in which the
bulk of the tungsten produced is used
according to Frank l.. Hess, in a re-
port on this metal just issued by the
United States Geological Survey. The
production of domestic tungsten ore
in 1911 amounted to l ,139 short tons
of concentrates, carrying GO per cent
of tungsten trioxide, valued at SlO',-
9S5; in 1910 the production amount
ed to 1921 short tons, valued at
sS32,992.
Tungsten is used chiefly in making
steels that will hold their temper when
heated, but it is most generally known
as supplying the fiament of tungsten
incandesccnt lamps. The great I'M
provmrnts in drawing tungsten wire
and further notable Improvements in
the size of the globe of the tungsten
lamp and in other mechanical details
that add greatly to its efficiency are
making it encroach upon the carbon
filament lamp and the arc lamp, and
it is rapidly driving from the market
the tantalum lamp, which was the
first good incandcsccnt lamp having
a metallic flamcnt. Diamonds are
used for dies in drawing tungsten
wire. At first it did not seem posi-
Bile to drill small enough holes through
the diamonds to make wire sufficient
ly fine for lamps of small candlcpow-
rr, but wire O.OO06 inch in diameter
can now be drawn in quantity. The
total quantity of tungsten ore used
for electric lights, however, amounts
to only a few tons year. New uses
of tungsten, in making electric fur
naces, electric contacts, and targets
for Roentgen rays, have been develop
ed, and the last two products are be-
ing actively manufacted.
Even for purposes of war tungsten
may have its uses, and investigations
are now being made with a view to
its application in the manufacture of
projectiles.
The present small-arm service pro-
jectile is made of lead with a Jacket
of copper-nickle alloy. The principal
advantage of lead over iron, which
would of course be cheaper, is that
it has higher specific gravity. Be
cause of this fact a lead bullet will
have a smaller cross section and will
consequently give tlatter trajectory
and longer range. An iron bullet of
the same diameter as the lead bullet
could of course be made of the same
weight by increasing its length, but
this would at once necessitate giving
it higher rotational velocity to keep
its axis tangential to it's flight. To
impart this added rotational velocity
would call for the expenditure of en-
ergy and SO leave less for velocity of
translation. With the exception of
tungsten, lead is the densest metal
which can be considered for this pur-
pose, for gold is the cheapest Of the
other elements having higher spe-
cific gravity than lead.
For military purposes the softness
of lead is not an advantage, a soft
nosed bullet being tabooed in civilized
warfare. For this reason and because
OF the fact that it is too weak to hold
the rifling it has to be jacketed with
copper-nickel alloy. To take the
rifiing and to act as gas check, the
tungsten bullet will require a copper
band or its equivalent at the base.
The hardness and high tensile
strength of wrought tungsten will give
high penetrating power. The high
melting point of tungsten will prevent
the projectile from being harmfully
upset at the base by the combined ac-
ton of the high temperature and
rapid impact due to the combustion
of the powder charge.