Evening star., 1914-07-18
NEW MUSEUM EXHIBIT
SHOWS GLASS WORKERS
Gift of Pittsburgh Concern Regard
ed as a Valuable Ac-
QUESTION.
Shows Processes From Assembling
of Materials to the Com
pleted Product.

sion of mineral technology of the Ma
tional Museum is an industrial series
in glass manufacture. The series shows
the original ingredients with their
natural sources. leads through the
different stages in the process of their
conversion from a granular mixture
to pure, amorphous glass, and gives a
faithful representation in model form
both of the furnaces and of the work.
ers engaged in the art of blowing.
molding and trimming the familiar
glassware, from the molten liquid Of
the furnace to the finished product
The exhibit Is the gift of a large glass
company Of Pittsburgh. and was de-
signed and prepared under the per-
sonal direction of the president of the
company.
When completed the series will start
with the ingredients entering into the
composition of glass essentially.
quartz sand. with alkali and alkalt
earth compounds. to lower the melting
point of the quartz together with the
coloring matter-showing these in their
natural state, both as the mineral
crystal and in the more common ore
form. and also the refined article pre-
pared for use. The refined samples, by
their relative sizes, indicate the gen.
eral proportions in which the different
ingredients enter into glass. The va
rious stages in the melting down and
fusing of these into molten glass are
demonstrated by series of large sam
pies showing successive conditions to
the final one where the glass is ready
for the worker.
Two Types of Furnaces.
Two standard types of furnaces in
which to melt glass, known respectively
as the tank and the pot furnace. are
in current use. The series includes a
model of each type along lines showing
the most up-to-date practice. These
are about one-sixteenth natural size
and are so constructed as to reveal
working details throughout with a re-
finement of method calculated to ap-
peal to technical as well as popular
interest Each Is of the gas-hred re-
generative type, fed from Swindel
patent producer. also shown in its
proper relationship to the furnace.
The tank furnace, as may be inferred.
derives its name from the receptacle
in which the molten glass is held. The
furnace proper consists of two COM
partments, a rectangular vault and a
dome-covered circular tank. The In
gradients are fed in at one end of the
former. which is also the combustion
ess of fusion proceeds under the infiu-
ence of the heat of the burning gas
above, the resultant molten glass keeps
flowing toward the opposite end. where
it passes into the tank compartment.
/ Workers Modelled to Scale.
The cylindrical wall. inclosing the
latter. is supplied with a number of
openings or ports through which the
gatherers. as they are called. have ac-
cess to the glass. Outside. on the main
floor of the building. around the tank,
fifteen workers. modelled to scale, will
show the various operations from the
first gathering" of the fluid glass on
the end of the blow pipe. through the
various acts of blowing up" mold
blowing. blocking. shaping, trimming,
ETC.. to the finished bottle lamp Chin
ney or other familiar article of every
day life.
In the pot furnace. as the name i'm
plies. the ingredients are in large re-
fractory pot or crucible. which is insert
and left to fuse. Subsequent opera
tions conform with those shown in
connection with the tank furnace and
smaller detail models serve to exem-
plify Incidental operations.
An alcove of upright cases will in
close the models on three sides and
will afford an historical resume of the
glass industry. A selection of speci-
mems will exemplify the refnements of
modern attainment in the art of glass
making.
Taken as a whole the series with its
accompaniment of descriptive labels
will reproduce and summarize an in
dustry which, owing to the extreme
delicacy and beauty of the medium
treated and to its significance in every
ing of any in the industrial world.