IMPROVEMENTS IN THE MANUFACTURE OF GLASS BOTTLES AND OTHER GLASS GOODS, AND IN THE APPARATUS EMPLOYED THEREIN.
Year: 1879

page_text: LETTERS PATENT to George Grey Eunson, of Sunderland, in the County of
Durham, for the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF GLASS
BOTTLES AND OTHER GLASS GOODS, AND IN THE APPARATUS EMPLOYED
THEREIN.
"
Sealed the 1st July 1879, and dated the 17th April 1879.
PROVISIONAL SPECIFICATION left by the said George Grey Eunson at the
Office of the Commissioners of Patents on the 17th April 1879.
GEORGE GREY EUNSON, of Sunderland, in the County of Durham. "IMPROVE-
MENTS IN THE MANUFACTURE OF GLASS BOTTLES AND OTHER GLASS GOODS, AND
IN THE APPARATUS EMPLOYED THEREIN."
The Invention has reference more particularly to the manufacture of glass bottles,
but may also be applied with advantage in the manufacture of other glass goods,
and its objects are to avoid the formation of mould marks and the unevenness
generally called "hammering" or "hammer marks" and to put a finer polish or
"skin" on the glass.
The improvements consist in forming several openings in suitable parts of the
mould in addition to the ordinary outlets for air therefrom, and in the introduction
into the mould of any suitable substance, such for example as a mixture of plumbago
and oil or tallow, which as it vaporizes will constitute a sort of lining to the mould
and allow of the bottle being turned in the mould, or of the mould being turned on
the bottle during the blowing process, the effect of which is that no mould marks
or "hammering" are produced, while the glass receives a much better polish or
skin than when the ordinary mode of manufacture is followed.
The openings before referred to may be made at the bottom of the mould and
at the shoulder, or at such other parts as experience may dictate.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said George Grey Eunson in the Great Seal Patent Office on the 17th
October 1879.
GEORGE GREY EUNSON, of Sunderland, in the County of Durham.
"IMPROVE-
MENTS IN THE MANUFACTURE OF GLASS BOTTLES AND OTHER GLASS GOODS, AND
IN THE APPARATUS EMPLOYED THEREIN."
The Invention has reference more particularly to the manufacture of glass bottles,
but may also be applied with advantage in the manufacture of other glass goods
which are circular in section, and its objects are to avoid the formation of mould
marks and the unevenness generally called "hammering" or "hammer marks" and
to put a finer polish or skin on the glass.
The improvements consists in the introduction into the mould of any suitable
substance, such for example as a mixture of plumbago and oil or tallow, which by
combustion will produce a gas to form a sort of lubricating lining to the mould and
allow of the bottle being turned in the mould, or of the mould being turned on the
bottle during the blowing process, the effect of which is that no mould marks or
hammering are produced, while the glass receives a much better polish or skin than
when the ordinary mode of manufacture is followed.
Instead of or in addition to the ordinary outlets for air from the mould which it
has been the custom to make at or near the centre of the bottom, I am enabled, owing
to the turning of the bottle and to the glass therefore not blowing into the holes, to
have openings at those parts of the mould where the glass is longest in taking its form,
which in the case of bottles will be at the edge (where the bottom joins the sides)
and at the neck and shoulder. The air and gases will thus readily escape, and the
glass will take the forn: of the mould more easily; the openings at the edge will
also allow any of the plumbago or other material used to form a lining as aforesaid,
and which may fall to the bottom of the mould, as well as particles of loose glass
to escape.
In the accompanying Drawings I show several forms of moulds suitable for
carrying my Invention into effect. Figure 1 represents in side elevation, and
Figure 2 in horizontal section through the line x, x, a mould composed of halves a, a,
which open the full length of the bottle and are hinged in the ordinary manner;
c is the mould bottom which is formed separately from the body a. There are four
openings d, d, (there may be more or less) at the edge of the mould, which openings
may be formed either by cutting away parts from the body a, as clearly seen in
Figure 2, or by forming openings at the edges of the bottom as shown at d, d, Figures 5
and 6. In addition to the openings d, d, there may be one or more air outlets e as
usual near the centre of the bottom, but I find in practice that with the openings
d, d, the ordinary air outlets e may be dispensed with. The joint 6 between the
halves a, a, of the body is not as has hitherto been the case made as close as
practicable; on the contrary I make the joint open as shewn, so that air and gases
may escape through the same. As the bottle is caused to turn with a reciprocating
rotary motion during the blowing operation the glass will not, as would otherwise
be the case, get blown into the holes d, d, or into the joint b, but the rotation of the
bottle will have the effect of putting a good skin thereon and of entirely preventing
mould marks and "hammering.'
"
In order to enable the blower the better to turn or hold the pipe it should have
a wooden handle fixed round it, about 6 inches long, or instead of turning the bottle
the mould may be made to revolve by any suitable mechanical means, but I prefer
to turn the bottle itself.

page_text: Figures 3 and 4 represent a mould in which the body part a is in one piece while
the part for the shoulders and neck is made in halves f,f, hinged to the body part a,
the joint b between them being open as with the joint in Figure 1. I prevent mould
marks at the joint g between the body and shoulders by having projecting pieces h, h,
on the body a to take into corresponding recesses in the parts f, f, so that as the
bottle goes round these pieces will rub out or efface the joint mark, or any other
suitable arrangement for the same purpose may be adopted, such for instance as
making the joint g' zigzag, or wavy, or vandyked, or by having it inclined instead
of horizontal.
In order to enable the plumbago or other material the better to adhere to the
mould the latter had better not be smooth; therefore instead turning out or scraping
and then polishing the interior of the mould as has hitherto been usual, I use the
mould, if cast truly internally, as it comes from the foundry with its rough skin, or
it may be roughly trued if necessary. Existing moulds may be adapted for use
according to my Invention by roughening the inside like a file or otherwise. The
mould should be cleaned occasionally, say once or twice daily. The mould must be
slightly larger than the bottles are intended to be; it should be prevented getting 80
hot as to burn off the lining rapidly; for this purpose either the mould may be cast
very heavy or two (or more) moulds may be worked alternately, or other suitable
means may be adopted to keep the mould from getting too hot."
When it is required to have letters or other marks on the bottom of the bottle
the piece on which the letters or marks are engraved should be circular and loose,
so as to go round with the bottle, see Figures 5 and 6, in which i is the loose piece
and c the mould bottom.
With regard to the material used for the lining I prefer to employ powdered
plumbago mixed with oil or tallow, it may be conveniently introduced into the mould
by dipping into the mixture a cloth tied round one end of a stick and then rubbing it
round the interior of the mould as required; care should be taken not to have the
mixture clotted as streaks would be formed round the bottle. Various other substances
may be used instead of the plumbago and oil or tallow, for instance the different forms
of charcoal, or soot, or resin mixed with oil, tallow, or wax; oil, tallow, or wax may
be used alone in a smooth mould, but this is not to be recommended as I find that it
burns off very rapidly and has to be renewed every time, while a mixture of
plumbago and oil will generally last for 2 or 3 dozen bottles.
By means of my Invention I am able to make in a more regular shape, and with
a good polish or skin water bottles, decanters, and other like articles which it has
hitherto been the practice to make without moulds because the mould marks and
hammering" have spoiled their appearance.
And having now described the nature of my said Invention, and in what manner
the same is to be performed, I declare that I claim as my improvements in the
manufacture of glass bottles and other glass goods, and in apparatus employed
therein,―
First. The introduction into or employment in the moulds of a substance which
by combustion will produce a gas to form a sort of lubricating lining thereto, sub-
stantially as and for the purpose herein before described.
Second. The causing of glass goods to revolve in their moulds, or the moulds to
revolve around the glass goods during the blowing operation, substantially as and
for the purpose herein before described.
Third. Constructing the moulds with openings for the escape of air and gas at
those parts where the glass is longest in taking the form of the mould, substantially
as and for the purpose hereinbefore described.
Fourth. Constructing moulds substantially as represented in Figures 1 and 2 and
hereinbefore described.
Fifth. Constructing moulds substantially as represented in Figures 3 and 4 and
herein before described.
Sixth. In moulds in which the bottle or other article is made to revolve, or which

page_text: are made to revolve around the bottle or other article as hereinbefore described, I
claim a loose piece or ring, substantially as shewn in Figures 5 and 6, and for the
purpose set forth.
In witness whereof, I, the said George Grey Eunson, have hereunto set my
hand and seal, this Fifteenth day of October, One thousand eight hundred
and seventy nine.
GEORGE GREY EUNSON. (LS.)