Spirit of the age. [volume] (Woodstock, Vt.) 1845-1913, 1897-02-27
BLENDING CoLORs IN GLASS.
Pittsburc Glass Blowers Expert In This
Branch of the business.

PittsburG GLASS Blowers Expert In This
Branch of tn" Business.
Glassmakiug legan in the United
States about 100 years ago, and at
first was confined to the manufac-
ture of ordinary articles required in
this country in those early days.
Step by step advances have been
made until now the manufacture
covers practically all articles where
single color of glass is used. The
Westinghouse glass factory in Pitts
burg, which was started Il few years
ago to make Il better quality of glass
than could he Obtained commercial
" for incandeScent electric lamps,
also took up the manufacture Of fine
gas and electric shades and is now
introducing commercially into the
making of shades composed of two
or more glasses of different colora
laid one on top of the other while in
Il molten condition, a process known
as flashing. The shades to which
especial attention 10 being given are
those which are green outside and
white inside and which are familiar
to every user of gas and electric
light. 1t will be Il surprise to many
to learn that all of these green and
4, .,h,ln-, how, hn,.nITfn,.n hnn,,
imported, most of them coming from
Germany.
However, through the discoveries
of their chemists, the Westinghouse
people are making shades far supe-
rior to the imported ones, particu
larly in the brilliancy of the white
glass used for the inside lining and
in the fine luster and even distribu-
ton Of the green glass used for the
outside of tho shades
In making these shades the work
man first takes from the furnace on
an iron pipe about as long as a
broom handle Il small ball of the
white glass, which he expands like
a soap bubble by blowing through
tho pipe until it is little larger
than an orange. While this glass is
still white not and soft it is dipped
into the furnace or pot containing
the green glass, thus giving the
white glass Il coating of green. The
ball is then blown to the proper size
for the kind of shade to be made,
and with a tool somewhat like a
pair of shears Il hole is made in rho
bottom of the hail, and by putting
proper tools inside of the ball
through this hole tho shape of the
ball is changed to the shape of the
desired shade. During the entire
process the pipe is kept revolving by
the workman, SO that the ball of hot
glass will not get ont OF shape.
From this description the process
of "hashing Will poo,n simple
enough, and wonder will be exples
ed that these shades have not been
made in this country before. The
reason is equally simple. Glass ex-
pands and contracts, just as iron
does. When two kinds of glass arc
flashed together as described above,
if their compositions are not prac-
tically the same, their expansions
and contractions will be different,
and the shades will crack as soon as
they cool. To make the green and
white so that they will have the
same degree of expansion has been
the difficulty, the composition of the
glass used in Germany having been
kept secret.
Flashing opens the way to infinite
variety in glas5working. Combina.
tons of all shades of color are pos
sible, and by cutting through the
outer colors marvellous "camco eff.
fects' are produced. America is
thus step by step going forward III
the art of glassmaking, as she has in
iron and steel and other industries,
and it may be safely predicted that
the art of glass flashing has obtained
a commercial footho]d; that every
kind of artistic glass will be made
here within Il few years, when cX.
portations will take the place of i'm
portations, and American glassware
will take the first place in tho mar.
kets of the world. Pittsburg Dis.
patch.