Year: 1869

"There is another process" con-
tinued the gafer, "by which our
common window glass is made. By
the way, if ever you visit Pittsburg,
in Pennsylvania, you must go into
the window glass factory there; you
will find them very curious. Their
furnace. in the first place, is built in
the ancient style; it has no chin
ney, and the smoke from the bitum-
inous coal they burn, pours out in a
cloud into the room. There are
openings in the roof for it to escape
through, and continual draught of
air from the doors carries it upward,
so that it is not so bad for the work
men as one would think Besides,
they do not begin to blow until the
smoke is all burnt off.


"There are five pots on each side
of the furnace; and you will see five
men IN a row, blowing all at once,
with the regularity of a file of sol
diers exercising. Each one gathers
thirty or forty pounds of metal on
his pipe, which is very long and
strong. They stand on platforms,
to get room to SWING the glass, as
they blow it. The five men begin
to blow and swing altogether. Each
blows 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 five rollers are swung up
towards the furnace 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 sup
port them while the rollers are being
reheated in the necks of the pots
The blowers blow in the necks OF
pipes with all their might, then clap
their thumbs over the holes to pre-
vent 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 it outwards. The glass
is then cylinder, opened at one
end. 1t is whirled in the heat until
the edges become true, then brought
away-the five iron supports drop.
ping to the ground with simulta-
neous clang. The cylinders are laid
on tables, where the imperfect srher-
ical end about the blowing pipe is
cracked off from the rest by stripe
of melted glass drawn around it.
The cylinder is then cracked from
end to end on one side by means ot
red hot iron passed through it.
''In the adjoining building is what
is called the fattening oven. The
cylinders brought there are lifted on
the end of a lever, passed in through
a circular opening just large enough
to admit them, and laid on some flat
tening stones on the oven bottom
with the crack uppermost. The
oven bottom is circular, and it re-
wolves horizontally. AS the glass
softens, it separates at the crack,
and lays itself down gently and grad.
ual1y on the stone. The long cylin-
der is then a fiat sheet, three feet
wide, and nearly five feet in length
There are four openings around the
sides of the oven; at one the glass
is put in, through another a work
man sweeps the stone for it, a third
workman smooths it down with 6
| block as it comes around 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 a carriage
in the oven. This he does by means
of lever, furnished with sharp
broad blades at the end, which he
works in under the glass. When the
carriage is full, it is run through ar
annealing oven beyond.


"The opposite end Of the anneal-
ing 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 the table, and
commences ruling it faster than a
school boy rules his slate. His rule
is wooden rod five feet long, and
his pencil point is diamond. Ev-
cry stroke is cut. Not that he cuts
the glass quite apart indeed, he
seems scarcely to make scratch
Yet that scratch has the effect of
cracking the glass quite through, so
that it breaks clean off at the slight
est pressure. In this way the sheets
are cut up into panes of the requi-
site SIZE"


81 should think the diamonds
would wear OUT said Lawrence.


II remember" said the gaffer,
zone workman told me that single
diamond would last him two or three
years. 1t has fifteen or sixteen diff
ferent edges, and when one edge is