IMPROVEMENTS IN THE MANUFACTURE OF GLASS
Year: 1852

page_text: LETTERS PATENT to Julian Bernard, of Guildford Street, Russell
Square, in the County of Middlesex, Gentleman, for the Inven-
tion of "IMPROVEMENTS IN THE MANUFACTURE OF GLASS."
Sealed the 23rd April 1858, and dated the 30th October 1852.
PROVISIONAL SPECIFICATION left by the said Julian Bernard at
the Office of the Commissioners of Patents, with his Petition,
on the 30th October 1852.
I, JULIAN BERNARD, of Guildford Street, Russell Square, in the
County of Middlesex, Gentleman, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF GLASS" to be
as follows:-
This Invention relates to the more economical and superior manu-
facture of glass than by existing processes. Instead of rolling the
glass, it is pressed or cast between two surfaces, which surfaces are
made to press or come in contact with both sides of the metal or glass.
From between these surfaces the atmosphere may be extracted by
suitable arrangements, which will have the effect of keeping the glass
free from air bubbles, and producing a flatter and more perfect surface

page_text: than hitherto. When the surfaces are made in the form of flasks or
chambers, the interior of such chambers or flasks may be put into
communication with the metal or liquid glass, the atmosphere being
then extracted to cause the metal to flow through the connection into
the chamber. These plates or surfaces may be arranged so as to be
pressed together after the metal has been introduced. By this means
the glass may be pressed into flat even plates, so as to require little or
no subsequent grinding, whilst the primary rolling process is dispensed
with, and the plate, or moulded or pressed piece, is produced quite free
from air bubbles. Then, instead of polishing the rough, rolled, or
pressed glass for mirrors and other purposes by hand, the polishing is
effected by machinery fitted with an extensive series of small polishing
buffers or rubbers, faced or not with glass or other material, working
upon the glass surface with differential motions, each acting through
an orbit or polishing motion of very limited extent, whilst the frame
containing the complete set of buffers or polishers has communicated
to it a separate motion. By such a system of polishing, the ordinary
system of expensive manual labor is done away with, whilst the glass
is better polished and more accurately than at present.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Julian Bernard in the Great Seal Patent Office
on the 30th April 1853.
TO ALL TO WHOM THESE PRESENTS SHALL
SHALL COME, I,
JULIAN BERNARD, of Guildford Street, Russell Square, in the County of
Middlesex, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirtieth day of October, in the
year of our Lord One thousand eight hundred and fifty-two, in the
sixteenth year of Her reign, did, for llerself, Her heirs and successors,
give and grant unto me, the said Julian Bernard, Her special license
that I, the said Julian Bernard, my executors, administrators, and
assigns, or such others as I, the said Julian Bernard, my executors,

page_text: administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS
IN THE MANUFACTURE OF GLASS," upon the condition (amongst others)
that I, the said Julian Bernard, by an instrument in writing under
my hand and seal, should particularly describe and ascertain the nature
of the said Invention, and in what manner the same was to be
performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date
of the said Letters Patent.
NOW KNOW YE, that 1, the said Julian Bernard, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement, reference being had to the accompanying Drawings,
and to the letters and figures marked thereon, that is to say:
My said Invention relates, first, to an improved mode of casting,
pressing, and shaping the material in the process of its manufacture;
and, secondly, to an improved arrangement of machinery for polishing
plates of glass.
Figure 1, on Sheet 1, of my Drawings, represent a vertical sec-
tion of my improved machine for casting, pressing, and shaping
the material. Figure 2, is a corresponding plan of the same,
with the upper portion removed, and uprights or guides shewn in
transverse section. Figure 3, is a detached plan view of a duct or
channel for admitting the glass into the mould. Figure 4, is a plan of
a portion of the casting table; and Figure 5, is a vertical section of a
portion of the same. A,, is the main support of the apparatus, having
a chamber B, formed within it to receive the piston or ram C, of the
rectangular casting bed or table D. This table is fitted with guiding
lugs E, which slide against the vertical supports or pillars F, F. The
ends of these pillars are let into slots in the sides of the main support A,
and upper fixed table G, and secured therein by metal plates H, bolted
over them. The upper and lower pressing tables are both made hollow,

page_text: aud fitted with ingress and egress pipes I, and J, for the admission of a
current of hot air, steam, or water within the tables, for the purpose of
heating them previously to the running in of the metal, and gradually
cooling them while the metal is hardening. K, K, are four bars of
equal thickness, which are laid upon the surface of the lower table near
its sides, as shewn in Figures 2, and 4. These bars regulate the
amount of space left between the upper and lower table, and therefore
the thickness of the plates to be cast will depend on the thickness of
the bars. They are fixed into their places by being fitted over a series
of short projecting stud pins L, L, secured to the lower table, these
pins fitting into corresponding holes in the bars. In order to allow of
the casting of plates of various thicknesses a number of these bars
are required of different dimensions. A curved duct or inlet M, for
the introduction of the metal is attached to the side of the lower table
by cotters N, N, and is supported by the bracket O, bolted to the
under side of the table. This duct is cast in two pieces longitudiually,
which are kept together by bolts passed through the flanges P, on each
piece. A stop cock Q, is fitted to the upper portion of the duct, the
extremity of which is lipped or formed with a flange R, which is slightly
dished to receive the spherical bottom of the pot or crucible S. Tho
curve of the hollow in the flange or lip R, being of larger radius than
that of the bottom of the pot, a certain amount of space is left for the
introduction of a small quantity of melted glass to form an air-tight
joint with the duct M. It will be seen, on reference to the Drawings,
that the bars K, K, form the sides of the space T, between the two
tables; aud in order that these sides may be made air-tight at the
junction surfaces, a packing of caoutchouc U, or other suitable material,
is laid against the joints all round the lower table, as shewn in the
plan view, Figure 2. An exhaust pipe V, fitted with a stop cock W,
is attached to the upper table, and connects the space T, with any
suitable exhausting apparatus. This is for the purpose of producing
a partial vacuum in the chamber or space T, by which means the glass
will be free from air bubbles, and will enter the mould more rapidly
than under the ordinary system. In casting B plate of glass by this
apparatus I close the cock Q, in the duct M, and exhaust the air from

page_text: the space T, by the pipe V, producing as perfect a vacuum as possible
The small cock W, is then closed, and the junction of the crucible and
duct M, is made air-tight by pouring a small quantity of melted glass
round it. A sufficient quantity of melted glass is then introduced into
the crucible, and the cock Q, is opened, allowing the metal to enter
at once and fill the space T, between the tables. When the glass has
become sufficiently solidified, the bars K, K, may be removed by lower.
ing the bottom table slightly, and thiuner ones inserted in their place.
The lowering of the table is effected by allowing the fluid contained
in the cylinder or chamber B, to run off by an egress cock, not shown
in the Drawings. The bars K, K, having been thus removed, and
replaced by thinner ones, the air is again exhausted, and the lower
table with the glass upon it is pressed up against the fixed upper surface
or table by hydrostatic or other suitable pressure. This pressure may be
continued during the process of cooling, thereby giving a perfectly even
surface to the plate; and consequently the subsequent operation of
polishing will be much more rapidly and easily accomplished than can
be effected on plates constructed in the ordinary manner. When the.
glass is sufficiently cool it is removed from the casting table to undergo
the next progress of its manufacture; this may be effected by lowering
the bottom table, as herein-before described, and severing the con-
nection between the glass in the duct M, and table V, by a heated iron
or other convenient means. In order to remove the cold or hard glass
out of the duct M, it is disconnected from the casting table by knocking
out the cotters, the crucible or pot S, having been previously removed
while the metal was in n plastic state. The duct being disconnected,
as stated, it is opened lengthwise by unfastening its flanges, and the
glass inside is knocked out and remelted. Although I have only shewn
the application of my process to the production of flat surfaces, it will
be obvious to the practical man that the same principle is applicable
to any form of mould or shape, suitable arrangements being made for
exhausting the air from the moulds, aud admitting the metal in a liquid
or plastic state.
Figure 1, on. Sheet 2, of my Drawings, represents a sectional eleva-
tion of my improved grinding, polishing, and smoothing machine;

page_text: and Figure 2, is a corresponding plan of the same. A, A, is the
fixed bed of the machine, which is fitted with a parallel V grooves
B, B; these grooves receives the slide rails C, C, which are cast on the
under side of the moveable table D. E, is the plate of glass to be
polished; and F, F, are the polishing buffers or rubbers, the rubbing
surfaces of which are fitted with suitable material, according to the
different operations of grinding, polishing, and smoothing which they
may be required to perform. The lower portions of the spindles G, of
the polishers or buffers are fitted with a metal disc H, to which is
secured the rubbing material, whatever it may be. These spindles are
carried by the moveable plate I, and frames J, which are bolted on to
it. Each spindle of the series of buffers, only two of which are shewn
in elevation in the Drawings, is fitted with a helical spring K, which
keeps each respective buffer pressed down upon the surface to be
smoothened. A pulley L, is keyed on to each buffer spindle, and
round each pulley is passed a driving band M, for the purpose of giving
a rotatory motion to the buffers, as will be herein-after described. The
alternating movement or traverse of the table D, is effected by the
crank shaft N, which is carried in suitable plummer blocks O, O. The
crauks P, P, are connected by the rods Q, Q, with the table to be
moved or traversed. R, R, are fast and loose driving pullies, for giving
motion to the crank shaft; and S, S', are bevel wheels keyed on to the
ends of the shaft, for transmitting motion to the side shafts T, and U,
by corresponding gearing. The shaft T, carries a pinion V, which is
shown in dotted lines at Figure 1, and this pinion gears into a spur wheel
W, on the end of the upper shaft X. The opposite extremity of the
shaft has secured to it the single crank Y, which gives a lateral traverse
to the plate I, through the connecting rod Z. This plate is guided in
its movement by the pins Z, which work in the slotted brackets a, a,
bolted to the sides of the fixed bed of the machine. The shaft U,
receives its movement through the bevel wheel b, and has keyed on to
it a second bevil wheel e, which gears with a bevil wheel d, on the
vertical shaft or spindle e. This shaft is supported by the fixed bracket f,
and carries a spur wheel g, and pulley h. i,j, are similar shafts, supported
by the same bracket, and fitted also with pulleys h, and spur wheels g,

page_text: which gear one with the other. These pulleys give motion to the driving
bands M, which pass round the loose carrying pulleys M¹, and communicate
a rotatory movement to the series of buffers F, F. k, k, are chains or
ropes for raising the polishing frame after the process has been com-
pleted. In smoothing a piece of glass by this machine the plate to be
smoothed is laid on the table D, and the rubbers F, F, are brought to
bear upon it. On the machinery being set in. motion the table D, will
traverse to and fro, among the V-grooves; and the plate I, and frames J,
carrying the rubbers, will be simultaneously traversed in a transverse
direction by the crank Y. The whole of the rubbers F, F, are also
made to rotate at the same time, and it will thus be seen that they are
constantly changing the course of their various motions over the surface
of the glass. When this operation is completed the polishing frame is
elevated by suitable tackle, and the polished plate removed. The
machinery herein-before described under the second head of my Invention
is more particularly intended to be used in the process of smoothing, at
present performed by manual labor; but the same arrangement will be
obviously applicable to the processes of grinding and polishing, the best
known means or material being used on the face of the rubbers according
to the nature of the operation performed. It will be obvious, on
referring to the Drawings, that in place of making both the table D, and
plate I, moveable, the plate I, may be fixed, and the table alone moveable,
or vise versa, but I prefer the arrangement shewn in the second Sheet
of my Drawings.
Having now described and particularly ascertained the nature of my
said Invention, and the manner in which the same is or may be used or
carried into effect, I would observe, in conclusion, that I do not confine or
restrict myself to the precise details or arrangements which I have had
Occasion to describe or refer to, as many variations may be made there-
from without deviating from the principles or main features of my
Invention., But what I consider to be novel and original, and therefore
claim as the Invention secured to me by the herein-before in part recited
Letters Patent, is,-
First, the system or mode of casting, pressing, and shaping glass, as
herein-before described.

page_text: Second, the system or mode of casting glass by running it into moulds
in which a vacuum or partial vacuum has been produced, in the manner
and for the purpose herein-before described.
Third, the general arrangement and construction of mechanism
for grinding, polishing, and finishing glass plates, as herein-before
described.
Fourth, the system or mode of grinding, polishing, and smoothing glass
by a series of rotatory buffers or rubbers, arranged in a suitable frame, in
conjunction with traversing tables or slides, as described.
In witness whereof, I, the said Julian Bernard, have hereunto set my
hand and seal, the Thirtieth day of April, One thousand eight
hundred and fifty-three.
JULIAN BERNARD. (L.s.)