Perrysburg journal. (Perrysburg, Wood Co., O. [Ohio]) 186?-1965, 1870-07-01
How Common window-Glass is Made.

IT ever you visit Pittsburgh, in Penn
sylvania, you must go into the window
glass factories there you will find them
very curious Their furnace, in the first
place, is built in the ancient style 1t has
no chimney, and the smoke from the BIZ
luminous coal they burn pours out in q
cloud into the room. There are openings
in the roof for it to escape through, and
continual draught of air from the doors
carries 1t upward, 80 thai It is not 80 bad
for 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
furnaces and you will see five men in a
row, blowing all Mt 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.
They stand on platforms, to get room to
swing the glass, az they blow it. The
i've men begin to blow and swing all to-
gether. Each blowsa great globe of glass,
which is stretched out gradually by the
swinging motion into a cylinder, or roller,
as it 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
case are iron bars, that they set upright un-
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
1t outward. The glass is then cylinder,
open at one end. 1t is whirled in the heat
until the edges become true, then brought
away,-the five iron supports dropping
to the ground with 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
it. The cylinder is then cracked from
end to end on one side by means of
red hot iron passed through it.
In an adjoining building is what is
called the f1attening oven. The cylinders
brought there are lifted on the end of
lever, passed in through a circular open
| ing just large enough to admit them, and
laid on fattening stones on the oven bot
| tom, with the crack uppermost. The oven
bottom is circular, and it revolves hori-
zontally. As the glass softens, 1t separates
at the crack, and lays itself down gently
| and gradually on the stone. The long
| cylinder is then fiat sheet, three feet
wide and nearly five feet in length. There
are four openings aroundss the sides of the
| oven at one Il he glass isput in, through
| another a workman sweeps the stone for
| it, third workman smooths it down with
a block as it comes round to him, and a
| fourth, at the last opening, which is close
to the one at which it was put in, lifts the
sheet-partly cooled by this time-upon a
carriage in the oven. This he does by
means of a lever furnished with sharp,
broad blades at the ends, which he works
in under the glass. When the carriage is
full, it is run through an annealing oven
beyond
The opposite end of the annealing oven
opens into the cutting room. There the
carriages are pushed along central track
and unloaded at the stalls of the cutters.
The cutter has a table before him, with
measure marks on its edges. He lifts one
of the sheets, lays it on table, and com
mences ruling il faster than school boy
rules his slate. His ruler is wooden rod
five feet long, and his pencil-point is a
diamond. Every stroke is a cut. Not
that he cuts the glass quite apart indeed
he seems scarcely to make a scratch. YET
that scratch has the effect of cracking the
glass quite through, so that it breaks
clean off at the slightest pressure. In this
way the sheets are cut up into panes of
the requisite size.
l remember, one workman told me that
a single diamond would last him two OF
three years. 1t has fifteen or sixteen diff
ferent edges, and when one edge is worn
out he uses another. South American
Diamonds, such as he used, cost, he told
me, from six to thirty dollars each and
when they are worn out for his purpose,
he sells them for jewels to be put into
watches-J Z. Tr0sobTidge, IN Our Young
| Hnlka