The Colfax chronicle. [volume] (Colfax, Grant Parish, La.) 1877-1981, 1886-07-24
MAKING PLATE-GLASS.
Flattering Results Obtained by the Use
of Natural Gas as Fuel.

Cl8tteThuk RESULTS ODV8lneO tuo W
of Natural Gas rs Fuel
"There is plate of glass 66xs4 inches
which is the largest size made in thii
country" remarked prominent glas;
merchant of this city to areporter as he
was engaged in experimenting the un-
packing Of large box.
ssIt was made in Pittsburgh manu-.
factory with natural gas as fuel, and is
much superior to that made by coal,
since the sulphur even in the best and
purest coal blurs and coats the glass
with patches, while if smoke comes in
contact with it in the soft state per.
manent stain is caused. Besides, when
coal fuel is used the best of care can
not prevent ashes, dust and solid par
ticles from the furnace falling onto the
molten glass and making flaws.
"Gas fuel, however, has changed all
Of that, and has given Pittsburgh a
great advantage, and glass can be made
so much better and cheaper there that
all of the factories have found them
selves forced to go to Pittsburgh or go
to pieces In short time America can
compete with French and German plate
glass, where manufactured gas is used"
''How is this glass madep" asked the
newsman.
swell. the hardest and most interest
ing part is the blowing" was the
reply.
1.-The entire mass of molten material
must be blown into shape by the breath.
Messrs. Appert, of Clichy, France,
claim to have discovered process that
will make glass-blowing by the mouth
unnecessary, and it is to be hoped that
they have, as the process is very pain
full, and the men after few years be-
come pale-faced, with their cheeks
hanging limp in folds, and some cases
have been known where their cheeks
have worn SO thin that they actually
cracked"
"What are the materials used to
make the CLASP" was the next question
of the reporter.
Zone hundred parts of sand, thirty
parts of lime, forty parts of alkali and
some pulverized charcoal are put in a
friedrich pot, which is set in furnace
heated to an intense heat by gas and
are brought to molten state. A work.
man then plunges long wrought-iron
tube with a wooden handle and mouth
piece into the white-hot mass, and by
alternately cooling and rolling it finally
has ball of glass many pounds in
weight adhering to the end. He turns
it about until it becomes pear-shaped,
and then hands it to the blower, who
blows gently into it, at the same time
constantly turning it, until it becomes
the shape of a huge bottle. 1t takes
very strong man to do this, since for
plate of glass of this size the molten
material will weigh thirty pounds.
"After it has been blown into the
right shape" the speaker went on,
''the end of the pipe is closed up, and
the air, expanded by the heat, breaks a
small hole in the end of the bottle,
which the blower enlarges by twisting
his tube around and putting his breath
into it until at length the bottle be-
comes cylinder. A string of red-hot
glass drawn over the upper part of the
cylinder breaks it off evenly, and it is
then cracked open lengthwise by red :
hot iron. Each side is heated, fiattened
out, tempered and polished, and finally
becomes a great sheet of clear plate
glass. Cincinnati Sun.