Clinch Valley news. [volume] (Jeffersonville, Va.) 18??-2019, 1902-08-15
GLASS FOR WINDOWS
THE METHOD AND THE MATERIALS
OF ITS MANUFACTURE.

1 y
People who have glass windows In
their homes do not know that the glass
contains enough arsenic to make IL q
deadly poison. Glassmakers say that
the windows OF an ordinary home con-
tain enough Of this poison TO kill a reg
iment OF men. The popular superstition
that glass Is made of sand is a correct
one. but quantity of other articles en-
tiers into Its composition.
Window glass factories are divided
into two departments, a tankhouse and
| pothouse- The process OF glassmak-
| Ing In one OF these departments IN prac-
tically the same as In the other. In the
farmhouse the glass is all melted In i'm
mense tanks which will hold thou
sands OF tons. In the pothouse the
glass is made In pots.
After the fires are lighted and tank
is heated the glass mixture Is shOveled
In 1t includes glass left over from the
former season. glass refuse. sand and
salt cake. Arsenic is not used In the
tankhouse for the reason that the heat
Is so intense that the drug Is volatilized
and escapes into the air without enter
Ing the mixture. AS one mixture melts
and flows to one end of tank fresh
supplies are shoveled In Mt the other
end
The molten mass seethes and
works" in a manner similar to that OF
mash I'm a distillery. From the salt
cake comes a salt water that has to be
separated from the mass, and the east
est way to remove 1t is to burn it out.
This is done by throwing stove wood
into the tank on top OF the molten
glass The water is converted into
steam. which is destroyed by the in
tense heat from the glass. The melted
glass is then skinned by an automatic
skinner. and Ii Is ready for the gath
erer
A gatherer thrusts q long steel blow
pipe Into one OF the rings at the lower
end OF the tank. He twists and turns
It until a small bah of glass gathers on
the end. This ball is partially cooled,
polished by being turned in a box OF
sawdust and then passed on TO the
blower. who heats II again until II be-
comes like taffy. The blower swings
the ball over a pit that is twelve feet
deep and rapidly blows it into an elon-
gated pear shape. When a blower Is
through, the melted glass becomes a
perfect cylinder about feet long and
feet across. 1t then passes to g SNAP
per-" who takes IL to a rack and breaks
the roller loose from the blowpipe.
The snapper gathers a small lump
or melted glass on the end OF n rod
and dexterously runs n narrow ribbon
OF the stun around the ends OF the
roller, both at the blowpipe end and
the closed end The little ribbons of
melted glass cool in a few seconds
when they are removed, leaving a mar
row zone OF almost redhot glass
around the rollers at each end. Then,
taking tool that resembles a soldering
iron. the snapper rubs IT for moment
on his forehead, and when the point OF
1t Is moistened with perspirntion he
runs the iron around the rollers at the
heated spot. The glass cracks and
separates as Clearly as II cut with a
diamond, the blowpipe is removed. and
the closed cylinder has become q roller
and is then ready to so to the fat
tener
The .hattener works In another part
OF the building, where are located the
hattentng ovens. These ovens are heat
ed to temperature sufficient to soften
the glass so that it may be rolled out
into sheets. A series Of fireclay tables
placed In a circle like the spokes of O
wheel revOlve in the ovens, and on
these tables the rollers are fattened.
They are placed inside, allowed to be.
come hot. and then cold iron is run
along the inside from end to end The
contact OF the iron cuts the glass.
which Is then Strengthened out upon
| the table.
The hattener has number OF bilIets
OF green wood attached to long iron
handles. and with these billets. which
are shaped in such manner as to do
the work expected of them, he irons"
the softened sheet of glass until Il Ia
| perfectly fiat and smooth The tables
inside the oven revOlve. the fattened
sheet is carried away. and another roll
er Is brought into position before the
hattener. AS the fattened sheets cool
they are lifted to a place on a long
travelling rack. on which they are by
stages removed from the ovens, being
allowed to cool as they go. This is done
In order that the glass may not be
shattered by too quick an exposure to
| the air.
When the sheets are taken from the
hattening ovens. they are covered with
greasy. dirty looking coat OF chem
icals-soda, potash. silicateS OF the DIFF.
rerent salts, etc.-which must be re-
moved, and for this purpose the rough
sheets are placed In an acid bath COM
posed OF hydrochloric and sulphuric
acids more or less diluted. After theIr
immersion In this bath the sheets are
taken to the cutting room. where work.
men cut them into sizes and mako
them ready for the packers. Hardly a
scrap OF the glass except the rough
edges Is wasted In fact. none Is vast
ed. as all refuse goes back to be melt
ed After the cutters have finished
their work the glass is packed In boxes
and Is then ready for the market.-In>
dianapolis News.