The Plymouth Democrat. (Plymouth, Ind.) 1869-1941, 1870-06-30
Hcw Common Window-Glass is Made.

If ever you visit Pittsburgh, in Penn
| sylvania, you must 90 into the window
glass factories there; YOU will find them
very curious. Their furnace, in the first
place, is built in the ancient STYLE: IL has
no chimney, and the smoke from the bi
luminous coal they burn pOurs out in a
cloud into the room. There are openings
IN the roof for il to escape through, and
continual draught Of air from the doors
carries it upward, so thai it is not 50 bad
Tor the wOrkmen as one would think. Be
sides. they do not begin to blow until the
smoke is all burnt off.
There are five pots on each side of the
furnace; and Won will see FIVE men in
row. blowing all at once, with the regulari-
ty of file of soldiers exercising. Each
gathers 30 or 40 pounds of metal on his
pipe, which is very long and strong.
lhey stand on platforms, 10 get room 10
SWING the glass, pc they blow IL The
hve men begin 10 blow and swing 81 to-
gether. Each blOwsa great globe of glass,
which is stretched out gradually by the
swinging motion into cylinder, or roller,
as II is called, five feet long. Then the
i've rollers are swung up toward the fur
nace-holes. and five other soldiers spring
forward with their guns,-which in this
NDS thAN hOl Aildt AlltN etl uDflQnL uu-
der the five blowing pipes to support them
while the rollers are being reheated in
the necks of the pots. The blowers blow
In the necks of the pipes with all their
might, then clap their thumbs over the
hole to prevent the air from rushing out
again; in the meanwhile the end of the
roller is sOftened, so that at last the air,
forced in and expanded by the heat, bursts
IL outward. The glass is then a cylinder,
open at one end. II is whirled in the heat
until the edges become true, then brought
awav,-the FIVE iron supports dropping
tn the ground with a simultaneous clang.
The cylinders are laid on tables, where
the imperfect spherical end about the
blowing pipe is cracked off from the rest
by strip of melted glass drawn around
1t. The cylinder is then cracked from
end to end on one side by means of a
red hot iron passed through it.
In an adjoining building is what is
called the flattening oven The cylinders
brought there are lifted on the end of a
lever, passed in through circular open
ING just large enough 10 admit them, and
laid on flattening stones on the oven bot
tom, with the crack upnermost. The oven
bottom is circular, and IL revOlves hori-
zontally. AS the glass softens it separates
at the crack. and laws itself down gently
and gradually on the stone. The long
cylinder is then a fat sheet, three feet
wide and nearly five feet in length. There
are four openings around. the sides of the
oven at one he glass isput in, through
another workman sweeps the stone for
it. third workman smooths II do En with
a block as it comes round to him, and
fourth, at the last opening, which is close
to the one at which IL was put in, lifts the
sheet-partly cooled by this time-upon
carriage in the oven. This he does by
means of a lever furnished with sharD,
broad blades at the ends which he works
in under the glass. When the carriage is
full, it is run through annealing oven
bevOnd.
The opposite end of the annesling oven
opens into the cutting room. There the
carriages are pushed along a central track,
and unloaded al the stalls Of the cutters.
The cutter has table before him, with
measure marks on its edges. He lifts one
Of the sheets, lays it on a table, and com
mences ruling il flster than a schOOi-boy
rules his slate. His ruler is wooden rod,
FIVE feet long, and his pencil-pOint is
diamond. Every stroke is a cut Not
that he cuts the glass quite apart; indeed,
he seems sea rcely TO make a scratch. Yet
that scratch has the effect OF cracking the
glass quite through, so that il breaks
clean off at the slightest pressure. In this
way the sheets are cut up into panes of
the requisite size.
| remember one workman told me that
a single diamond would last him two or
three years. 1t has fifteen or sixteen diff
ferent edges, and when one edge is worn
ont he uses another South American
Diamonds. such as he used. cost, he told
mo from SiN m thirty I..llorc eaol
when they are worn ont for his purpose,
he sells them for Jewels to be put into
watches-J T. TrOr5ridge IN Our Young
Eya7Eo