The Democratic advocate. [volume] (Westminster, Md.) 1865-1972, 1869-06-17
Mistellaneous.
Manufacture of Glass Ware.

Having described, in former articles,
the composition and modes Of manuiac
turing bottles and window glass, our
readers will understand the methods
employed for pressed glass ware by
very brief description. The pressed
glassware is made by pressing glass into
molds Of iron, and the articles thus
formed Approximate in beauty and regu
larity OF form to those of cut glass, de.
scribed further on. The operation re.
quires less skill in manipulation than
glass blowing, but is, nevertheless, iu-
teresting.
1t will be best understood by dcscrib-
ing the manufacture of some special
article-say fruit dish, the bowl Of
which is shaped, aud its foot
formed like the bell OF trumpet. Such
an article would be made iu two parts,
the bowl aud the foot being pressed in
separate molds, aud afterwards Joined
together. A boy takes upon the end
OF an iron rod or "punty,' a quantity
of glass from the melting pot, aud holds
it over the open mold. The weight of
the molten glass causes it to depend 10
the form Of large pcar.shaped drop
The principal work man, who has charge
OF the mold, cuts off this drop with a
pair of shears, as soon as, in his Judge
ment, enough has depended to exactly
fill the mold. As soon as the glass has
fallen into the mold, it is closed with
lever which forces the glass into every
part Of the matrix. The molds are
made in two parts corresponding to the
convex and concave sides of the piece.
So accurate is the Judgment of the
skilled operators in this process that
they rarely fail to properly apportion
the glass to the capacity Of the closed
mold. The glass is removed from the
mold as soon as it cools enough to be-
come rigid, and is carried by an assist
ant to the annealing oven, If, as 10 the
particular case of the fruit dish, it re-
quires to be joined TO another portion,
it is cemented to its fellow by small
portion Of plastic glass, and then placed
in the annealing oven. Varieties Of
form and pattern may be attained by
this method which are impossible 10 the
blowing process, and the larger portion
of goblets, salt.cellars, and other glass
table ware, in common use, Is made in
this manner.
The finer and most costly articles of
glass ware, are finished by process
called cutting, which is, however, really
a grinding process, performed by means
of iron, sandstone, or copper disks, Of
various sizes aud forms, according to
the nature of the work to be performed.
The disks are fixed, by proper ehucks,
to lathes, and are supplied with sand
for rough grinding, and emery for finer
work. A stone wheel is also used to
efface the sand marks, and wood disks
are used for polishing, supplied, at first,
with mixture of pumice and rotten
stone, and finally with putty powder"
preparation of tin aud lead. Flint
glass is the best for this purpose, as its
superior hardness enables it to take
6ner polish. Great skill and artistic
taste is shown by the artisans, in this
department, aud cut-glass wares com
maud higher price than any others.
Plate glass constitutes large and
important branch Of the glass manufac-
ture, and may form the subject of
future article. The numberless uses to
which glass is now applied, render all
information, respecting its manufacture,
of value, and although the manufacture
Of plate glass has not yet been success
fully introduced into the United States,
the extent Of the demand here would
seem to justify further attempts at
home prodactiou.- Scientific Amsrican. ,