Delaware gazette and state journal. (Wilmington, Del.) 1883-1902, 1899-10-12
MAKING or "LBA y. PENCILS.
Graphite, Nor Lead, Enters into Their Con-
posiLinn.


Graphite, Nor Lead, Enters Into Their Com.
posiuon.
School and Home.
The first thing to be said about lead
pencils is that they are not lead pen
ellis at all. Once upon time sticks
of lead were used for making marks on
paper and wood, and the name has sur.
wired, though nowadays all the pencils
are filled with graphite, or glumbago
This mineral is found in only o few
places in the world--in Cumberland,
England, along the Laurentian ranges
in the Province of Quebec, and OF
Ticonderoga, Vt. The largest mines
on this continent are at the latter place
The graphite is taken in the lump
from the mines and carried to the re.
ducing mill, whore it is ground or pull
verified in stamp mills under water
The fine particles Of graphite float
away with the water through number
OF tanks, collecting at the bottom Of
these reservoirs. 1t is packed in
barrels in the form of dust and sent to
the factory, where tens of thousands Of
lead pencils arc turned out every day,
The pulyerized graphite is SO fine that
it really is dust, dingy in color and
smooth and oily to the touch. II is
divided into various grades of iineness
by floating it on water from one tank
to another. The coarse dust sinks to
the bottom of the first tank, the next
finer to the bottom of the second tank,
and so on down the line. the finest
powder for the finest pencils settling in
tho last tank
In another series of tanks the Ger
man pipe clay, which is mixed with
graphite to secure the different grades
OF pencils from very soft to extra hard,
is graded in the same way. by floating.
The finest clay is mixed with the finest
graphite, being ground together be.
tween stones, and the hardness OF the
pencil is secured by increasing the pro-
portion of clay in the mixture.
For the medium grades seven parts
byweight of clay are mixed with 10
parts Of graphite. After the graphite
and clay are ground together the mix
ture IS put in canvas bags and the
water Is squeezed out under hydraulic
press, leaving mass the consistency
OF putty. The plaster is placed in q
forming press, which is q small iron
cylinder. in which a solid pluneer or
piston works up and down. A steel
plate having hole the size and shape
OF the lead" is put under tho OPEN
nd OF the cylinder, and the plunger
pressing down forces the graphite
through the hole, making continuous
thread of wire of graphite.
AS long as this thread is moist it is
pliable, but it becomes brittle when
dry, SO it is handled rapidly. 1t is cut
into three lead lengths, Strengthened
out, and then hardened in crucibe
over coal fire. Theleads when taken
from the crucibles are ready for the
wood. which is pine for cheap pencils
ana cedar for more expensive ones.
When the strips of wood are received at
the factory they are run through
machine which cuts in each one six
groves. round or square, and at the
same time smoothes the face of the
wood.
Tho filling of the strips is done by
girls. Inc tirst ono takes a grooved
strip OF wood in her left hand and
bunch OF leads in the right. She
spreads the leads out fan shape, and
with one motion she fills the six grooves
with lead. Next to her sits another
girl, who takes the filled strips and
quickly and neatly lays on another
grooved strip which has Just been
coated &C, with hot glue by third girl;
Inc Tiled and glued strips are piled
upon each other and put in q press,
where they are left to dry. Tho ends
of the strip are evened off under a
sandpaper wheel, and then the strips
are fed into machine which cuts out
the individual pencils, shapes them
and delivers them smooth and ready for
the color and polish in six streams.
The coloring is done with LIQUID dyes,
nfter which the pencils are sent
throuph tho parnishinn ,,,nnhina