IMPROVEMENTS IN PROCESS OF AND FURNACES AND MACHINERY FOR TEMPERING FLAT AND SHAPED GLASS
Year: 1875

page_text: LETTERS PATENT to François Barthelemy Alfred Royer de la Bastie,
of Chateau de Richemond, par Pont d'Ain, France, for the Inven-
tion of IMPROVEMENTS IN PROCESS OF AND FURNACES AND MACHINERY FOR
TEMPERING FLAT AND SHAPED GLASS."
PROVISIONAL SPECIFICATION left by the said François Barthelemy
Alfred Royer de la Bastie at the Office of the Commissioners of
Patents, with his Petition, on the 12th June 1875.
I, FRANÇOIS BARTHELEMY ALFRED ROYER DE LA BASTIE, of Chateau
de Richemond, par Pont d'Ain, France, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN PROCESS OF AND FURNACES AND
MACHINERY FOR TEMPERING FLAT AND SHAPED GLASS," to be as follows: :-
My Invention has reference to the process and apparatus for tempering
glass, for which Letters Patent were granted to me bearing date the
12th August 1874, No. 2783, the said process consisting mainly of
A

page_text: plunging the glass when heated to about the point of softening into a
liquid bath of oleaginous substances at a somewhat lower temperature.
My present improvements have reference to the condition of the glass
at the time of plunging, to the constitution of the tempering bath, to
the manipulations required for the tempering operation, and to the
furnaces and apparatus employed.
In the Specification to my prior Patent I stated that the glass should
be plunged at the moment when it begins to soften; this is necessary
when treating articles of thick glass, but not with articles of thin glass
which I have found can be plunged at a lower temperature. Although
no doubt the best effect is produced in all cases if the glass is plunged in
the soft condition, yet with thin glass a high degree of tenacity is
attained if it is plunged even while still hard.
In my former Specification I described the bath for plunging the
glass as being composed of oils or fatty matters of animal, vegetable, or
mineral origin, and I stated that it should be heated to a lower
temperature than that of the glass to be plunged. It is however not
necessary that the bath should always be actually heated, so long as its
temperature is below that of the glass, such temperature depending
upon the nature of the glass to be tempered. Thus glass of a hard
quality requires to be tempered in a bath of high temperature,
while glass of a soft quality can be tempered in a bath of a lower
temperature; some glass can even be plunged in a cold bath at the
temperature of the surrounding atmosphere. Also the term "bath"
does not always imply that the substance composing the same should be
in a liquid condition, as the necessary cooling effect may also be
produced by plunging the articles into a bath composed of pulverulent
material or of gascous bodies, such as a current of air.
Furthermore, although I prefer to employ oils or fatty matters or
resinous materials, such as tar, pitch, bitumen, resin, and the like
for the bath, yet other substances may also be used; thus I have
found that in certain cases in place of such bodics may be used
water, saline solutions, molten metals, or alloys, alcohol, ether, glycerine,
essences, collodion, or pulverised refractory material, talc, licopodium,
plaster of Paris, vegetable flower, or molten sulphur or salts, such as
saltpetre.

page_text: Although I stated in my previous Specification that the article should
be plunged into the bath, yet it is not necessary that the article should
be precipitated into the bath, but that the substance of the bath should
be made to cover the article, which may be effected in any other known
manner besides actual immersion, such for instance as by pouring the
liquid, pulverulent or gaseous body over it. Whatever may be the
composition of the bath the glass article should be subjected to its action-
after having been raised to the necessary temperature. As this
temperature is naturally attained in the manufacture of the article it
may be at once plunged on the completion of the manufacture, thus
obviating the necessity of reheating.
Instead of effecting the tempering by one single operation of plunging,
the article may be plunged several times consecutively in order to give
it greater hardness, and the baths may be either of the same or of a
different character; thus a bath of hot oil may be first used, and the
article while still hot may be then plunged into cold or warm water;
also the article may after removal from the bath be subjected to a
reheating process.
The furnaces employed for carrying out the tempering process with
flat glass are according to my present improvements constructed with a
long compartment or passage at the side of the furnace with which it
communicates by means of a wide but very low opening. In this
passage is an endless travelling metallic web on which are placed, one
behind the other, the sheets of glass to be heated and tempered. As the
sheet of glass arrives in front of the before-mentioned opening the
workman by means of a long flat fork passed through a side hole lifts
the sheet slightly and pushes it through the opening into the heating
chamber of the furnace, where it is received on a moveable carriage
consisting of a flat slab of fire-brick on a framing supported by small
wheels running on rails on the furnace bed.
In order to insure the uniform heating of the sheet of glass, the
carriage is moved backwards and forwards in the heating chamber by
means of a long rod passed through the wall of the furnace. The bed of
the furnace is constructed with a double bottom, below which is the
framing and wheels of the carriage, which is thus protected more or
less from the heat of the furnace, a long slot being formed in the double
bottom through which passes the support for the fire-brick slab. The

page_text: slab or table of the carriage may either be fixed on its framing, or it
may be made to revolve thereon in order to present all parts of the glass
sheet to the action of the heat, and for this purpose it may be connected
by bevil gearing to a spindle extending through the wall of the furnace.
The furnace is heated by a fire-grate closed in by doors provided with
eye holes, the flames pass over a bridge to the bed of the furnace,
whence they pass partly through the side opening into the before-
mentioned passage with travelling web, and partly to a chimney.
provided with a damper for regulating the heat.
When the glass sheet has been sufficiently heated the carriage is pushed
towards a sole or moveable part of the furnace bed capable of being
canted, on to which the sheet is drawn by means of a rake. This
moveable part or sole consists of a refractory slab, which may be faced
with smooth porcelain supported on an irou frame which is mounted on
sliding rods that extend down to a shaft in the lower part of the furnace,
where they are fitted with screws for adjusting the level of the sole.
The shaft has an arm with a counterweight to balance the sole. The
supporting rods between the sole and the shaft pass through slotted holes
in a plate, which holes are covered by slides, so that heat cannot pass
down from the furnace nor air enter to inflame the material of the bath.
The glass sheet having been drawn on to the sole the attendant by
moving to an adjustable stop an external lever fixed on the shaft below
causes the sole to sway in an inclined attitude towards the bath which
is set in masonry adjoining the furnace. Between the furnace and the
bath is a long narrow opening closed by a vertical slide which is
connected by a chain passed over pullies to the lever that works the sole
shaft, so that the slide is raised as the sole is thrust partly through the
opening without admitting flame to the bath. The glass plate slides
from the inclined sole on to a grating mounted on a shaft, which passes
through the bath, the grating being inclined by means of an exterior
lever, so that it coincides with the plane of the inclined sole. The
grating for about a third of its length at the end next the sole presents
openings of losenge form, and it has longitudinal bars in the rest of its
length, and the lower end of the framing to which it is jointed has a
cushion of wire gauze, against which the edge of the glass impinges
without shock. When the glass is received on the grating the sole is
moved back into the furnace, the slide closing the opening after it.
When the glass has been immersed for sufficient time in the bath, the

page_text: grating is by means of the external lever raised to a horizontal position
in which it is retained by a latch, and the cover of the bath being raised
the glass is drawn by a rake into a receptacle divided by shelves into
several horizontal compartments, and mounted on a shaft worked by an
external lever, so that any one of these compartments can be presented
on a level with the grating for the reception of the glass sheet.
The shaft of the grating where it passes through the side of the bath
is fitted with a conical trunnion working in a conical seating adjustable
to prevent leakage, and the lever which works this shaft as well as that
fór working the shaft of the shelved receptacle is provided with a catch
engaging with notches on a fixed sector so as to hold the shaft in the
required position. The latch which holds up the grating when it has
been raised is on a spindle having on it an external arm, by moving
which after the glass is slid into the receptacle the grating is released
and drops down again into its inclined position in the bath.
Sometimes scum or crust forms on the surface of the bath; to prevent
this from interfering with the movement of the glass on to and along
the grating there is mounted near the opening from the furnace an
oscillating rake worked by a spindle and external handle, whereby the
attendant before moving the sole towards the bath removes the scum or
crust into a wire gauze receptacle under the bath cover. The bath is
provided with a syphon overflow pipe, whereby the level of its contents
is maintained constant.
In case of glass breaking on the grating the fragments may be
received on a sheet of wire gauze supported a little above the bottom of
the bath, and removed from time to time. The bath which is of metal
is set in the masonry with flues under and around it heated by a fire at
the side. Close to the fire is a chimney to which the products of com-
bustion are led from the flues by an underground channel. There is
also a direct passage into this chimney from the fire, and this passage
as well as that into the flues of the bath is provided with a damper, so
that according as the one or the other is more or less opened or closed
the temperature of the bath can be varied.
The cover of the bath is made in several parts hinged so that they
can be separately opened to give access to the receptacle of the
tempered glass, or to the crust or scum receptacle, or to the skimming
rake, and in a fixed portion of the cover is a thermometer which indicates

page_text: the temperature of the bath. There may also be a pipe for leading to
the chimney vapours evolved from the bath, and at the bottom of the
bath there is a pipe with a stop-cock or valve for emptying the bath.
The grating on which the glass plates are received may have rollers.
under which the glass slides, and by having these rollers heavier towards
the farther or lower end of the grating the velocity of the glass may be
gradually diminished before it reaches the end of its descent.
For tempering glass articles of forms other then flat sheets, I arrange
the furnace and bath in the following manner :-The sole on which the
articles are placed to be heated is mounted by arms on an axis worked
by an external lever. In its horizontal position this sole covers over the
top of the bath, which is morcover closed by a sliding plate under the
sole. When the articles are heated sufficiently they are moved by a
rake on to a narrow lateral sole, which is fixed on a level with the
moveable sole. The latter is then canted to one side so as to expose the
mouth of the bath, and the sliding plate being then withdrawn the
heated articles are pushed into the bath. To prevent them from striking
the sides there are fixed in the bath pieces of wire gauze inclining
downwards towards the middle which is open, forming a sort of funnel
by which the glass articles are guided down towards the middle opening.
Near the bottom of the bath an endless web of wire gauze is mounted
on rollers and guided by narrow rollers along its edges, and bars are
fixed at intervals across it. The glass articles are received upon this web
and when it is moved they are carried by it upwards in a sloping direction
and finally discharged from it at one end of the bath into a receptacle
made with a rounded bottom, in which receptacle there is suspended a
wire ganze basket which receives them, and by means of which they
are lifted out of the bath. Immediately under the sliding plate which
covers the opening into the bath below the moveable sole, is mounted a
wire gauze rake by which the crust and scum is withdrawn from the
surface of the bath before plunging the glass articles into it. This rake
is worked by an external handle on its spindle, and the sole is moved by
an external treadle which is connected by ratchet gearing to one of
the rollers of the endless web, so that every time the sole is moved the
web is made to advance.
For tempering special articles moveable baths may be employed
instead of the fixed bath, which I have described for tempering sheets.

page_text: In employing such a moveable bath, which is a flat rectangular vessel
containing a grating and having one end to open, I mount it by
trunnions on arms near the mouth of the furnace, and adjust it to such
an inclination as to coincide with that of the sole when it is canted. I
then open the end of the bath, and canting the sole towards it, cause the
articles to slide from the sole into the bath, which I then close and
remove, replacing it by another of the same kind.
For tempering cylindrical articles, such as lamp glasses, I employ an
apparatus which consists of a long spindle on which the glass is placed
between two cones or between a cone and a collar. This spindle is fitted
by a feather to slide through but revolve with a pinion, which can be
caused by gearing to revolve with considerable velocity, and the pinion
and its gearing are mounted by an arm on a horizontal axis. In one
position of this arm the spindle is horizontal or nearly so, and can be
slid with the glass on it through an opening into the furnace, where
being caused to revolve the glass becomes uniformly heated. The arm
is then moved into an inclined attitude whereby the end of the spindle
with the glass on it is canted down into a bath below the furnace
chamber.
The end of the spindle may be fitted with sleeves or collars of
refractory material to suit glasses of different forms, or may carry a
hollow cylinder of pipe clay or other refractory material, within which
a glass tube or other cylindrical piece can be placed, and out of which
it is dropped into the bath when the spindle is canted.
Tongs of various forms may also be employed to hold between their
jaws the glasses to be tempered while they are being heated, so that on
opening the jaws they drop into the bath, and when such tongs are.
employed I make them with a third arm besides the two which work
the jaws, this arm having attached to it a ring or parts of a ring, by
moving which the glass is separated from the jaws when it happens to
adhere thereto.
Small articles such as dishes, cups, and the like may be heated in
refractory moulds, so as to avoid spoiling their shapes, and plunged by
inverting these moulds and allowing them to drop into the bath.

page_text: SPECIFICATION filed in pursuance of the conditions of the Letters
Patent, and of an Order of the Lord Chancellor, by the said François
Barthelemy Alfred Royer de la Bastic in the Great Seal Patent
Office on the 18th April 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FRANÇOIS
BARTHELEMY ALFRED ROYER DE LA BASTIE, of Chateau de Richemond,
par Pont d'Ain, France, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twelfth day of June, in the
year of our Lord One thousand eight hundred and seventy-five, in
the thirty-eighth year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said François Barthelemy
Alfred Royer de la Bastic, Her special license that I, the said François
Barthelemy Alfred Royer de la Bastic, my executors, administrators,
and assigns, or such others as I, the said François Barthelemy
Alfred Royer de la Bastic, my executors, 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 PROCESS OF AND FURNACES AND
MACHINERY FOR TEMPERING FLAT AND SHAPED GLASS," upon the condition
(amongst others) that I, the said François Barthelemy Alfred Royer.
de la Bastie, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and scals, 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 Scal Patent Office on or before the
Twentieth day of April 1876.
NOW KNOW YE, that I, the said François Barthelemy Alfred Royer
de la Bastie, do hereby declare the nature of the said Invention, and
in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement thereof,
reference being had to the accompanying Sheets of Drawings, and to
the figures and letters marked thereon, that is to say :-
My Invention has reference to the process and apparatus for
tempering glass, for which Letters Patent were granted to me bearing

page_text: date the 12th August, 1874, No. 2783; the said process consisting
mainly of plunging the glass when heated to about the point of
softening into a liquid bath of oleaginous substances at. a somewhat
lower temperature.
My present improvements have reference to the condition of the glass
at the time of plunging, to the constitution of the tempering bath, to
the manipulations required for the tempering operation, and to the
furnaces and apparatus employed.
In the Specification to my prior Patent I stated that the glass should
be plunged at the moment when it begins to soften, this is necessary
when treating articles of thick glass, but not with articles of thin glass,
which I have found can be plunged at a lower temperature. Although
no doubt the best effect is produced in all cases if the glass is plunged
in the soft condition, yet with thin glass a high degree of tenacity is
attained if it is plunged even while still hard.
In my former Specification I described the bath for plunging the
glass as being composed of oils or fatty matters of animal, vegetable,
or mineral origin; and I stated that it should be heated to a lower
temperature than that of the glass to be plunged. It is however not
necessary that the bath should always be actually heated so long as its
temperature is below that of the glass, such temperature depending
upon the nature of the glass to be tempered. Thus glass of a hard
quality requires to be tempered in a bath of high temperature, while
glass of a soft quality can be tempered in a bath of lower temperature;
some glass can even be plunged in a cold bath at the temperature of the
surrounding atmosphere. Also the term "bath" does not always imply
that the substance composing the same should be in a liquid condition,
as the necessary cooling effect may also be produced by plunging the
articles into a bath composed of pulverulent material, or of gascous
bodies, such as a current of air.
Furthermore, although I prefer to employ oils or fatty matters, or
resinous materials, such as tar, pitch, bitumen, resin, and the like for the
bath, yet other substances may also be used; thus I have found that
in certain cases in place of such bodies may be used water, saline
solutions, molten metals or alloys, alcohol, ether, glycerine, essences,
collodion, or pulverised refractory material, tale, licopodium, plaster of
Paris, vegetable flour, or molten sulphur, or salts, such as saltpetre.

page_text: Although I stated in my previous Specification that the articles
should be plunged into the bath, yet it is not necessary that the articles-
should be precipitated into the bath, but that the substance of the bath
should be made to cover the article, which may be effected in any
other known manner besides actual immersion, such for instance as
by pouring the liquid, pulverulent or gascous body over it. Whatever
may be the composition of the bath the glass article should be subjected
to its action after having been raised to the necessary temperature.
As this temperature is naturally attained in the manufacture of the
article it may be at once plunged on the completion of the manufacture,
thus obviating the necessity of reheating.
Instead of effecting the tempering by one single operation of plunging,
the article may be plunged several times consecutively in order to give
it greater hardness, and the baths may be either of the same or of
a different character; thus a bath of hot oil may be first used, and the
article while still hot may be then plunged into cold or warm water.
Also the article may after removal from the bath be subjected to a
reheating process.
The furnaces employed for carrying out the tempering process with
flat glass are according to my present improvements constructed with
a long compartment or passage at the side of the furnace with which it
communicates by means of a wide but very low opening. In this
passage is an endless travelling metallic web, on which are placed, one
behind the other, the sheets of glass to be heated and tempered. As a
sheet of glass arrives in front of the before mentioned opening the
workman by means of a long flat fork passed through a side hole lifts
the sheet slightly and pushes it through the opening into the heating
chamber of the furnace, where it is received on a moveable carriage
consisting of a flat slab of firebrick on a framing supported by small
wheels running on rails on the furnace bed.
In order to insure the uniform heating of the sheet of glass the
carriage is moved backwards and forwards in the heating chamber by
means of a long rod passed through the wall of the furnace. The bed
of the furnace is constructed with a double bottom, below which is the
framing and wheels of the carriage, which is thus protected more or less
from the heat of the furnace, a long slot being formed in the double
bottom, through which passes the support for the fire-brick slab. The

page_text: slab or table of the carriage may either be, fixed on its framing or it
may be made to revolve thereon, in order to present all parts of the
glass sheet to the action of the heat; and for this purpose it may be
connected by bevil gearing to a spindle extending through the wall of.
the furnace. The furnace is heated by a fire-grate closed in by doors
provided with eye holes. The flames pass over a bridge to the bed of
the furnace, whence they pass partly through the side opening into the
before-mentioned passage with travelling web, and partly to a chimney
provided with a damper for regulating the heat.
When the glass sheet has been sufficiently heated the carriage is
pushed towards a sole or moveable part of the furnace bed capable of
being canted, on to which the sheet is drawn by means of a rake.
This moveable part or sole consists of a refractory slab, which may be
faced with smooth porcelain, supported on an iron frame which is
mounted on sliding rods that extend down to a shaft in the lower part
of the furnace, where they are fitted with screws for adjusting the level
of the sole. The shaft has an arm with a counterweight to balance the
sole. The supporting rods between the sole and the shaft pass through
slotted holes in a plate, which holes are covered by slides, so that heat
O cannot pass down from the furnace nor air enter to inflame the material
of the bath. The glass sheet having been drawn on to the sole, the
attendant by moving to an adjustable stop an external lever fixed on
the shaft below, causes the sole to sway in an inclined attitude towards
the bath, which is set in masonry adjoining the furnace. Between the
5 furnace and the bath is a long narrow opening closed by a vertical slide,
which is connected by a chain passed over pullies to the lever that
works the sole shaft, so that the slide is raised as the sole is thrust
partly through the opening without admitting flame to the bath. The
glass plate slides from the inclined sole on to a grating mounted on a
shaft which passes through the bath, the grating being inclined by
means of an exterior lever, so that it coincides with the plane of the
inclined sole. The grating for about a third of its length at the end
next the sole presents openings of losenge form, and it has longitudinal
bars in the rest of its length; and the lower end of the framing to which
it is jointed has a cushion of wire gauze, against which the edge of the
glass impinges without shock. When the glass is received on the
grating the sole is moved back into the furnace, the slide closing the
opening after it. When the glass has been immersed for sufficient time
c

page_text: in the bath the grating is by means of the external lever raised to a
horizontal position, in which it is retained by a latch; and the cover
of the bath being raised, the glass is drawn by a rake into a receptacle
divided by shelves into several horizontal compartments and mounted
on a shaft worked by an external lever, so that any one of these
compartments can be presented on a level with the grating for the
reception of the glass sheet.
The shaft of the grating, where it passes through the side of the bath,
is fitted with a conical trunnion working in a conical scating adjustable
to prevent leakage, and the lever which works this shaft, as well as that
for working the shaft of the shelved receptacle, is provided with a catch
engaging with notches on a fixed sector, so as to hold the shaft in the
required position. The latch, which holds up the grating when it has
been raised, is on a spindle, having on it an external arm, by moving
which after the glass is slid into the receptacle the grating is released,
and drops down again into its inclined position in the bath.
Sometimes scum or crust forms on the surface of the bath. To
prevent this from interfering with the movement of the glass on to and
along the grating there is mounted near the opening from the furnace
an oscillating rake worked by a spindle and external handle, whereby
the attendant before moving the sole towards the bath removes the
scum or crust into a wire gauze receptacle under the bath cover. The
bath is provided with a syphon overflow pipe, whereby the level of its
contents is maintained constant.
In case of glass breaking on the grating the fragments may be
received on a sheet of wire gauze supported a little above the bottom
of the bath and removed from time to time. The bath, which is of
metal, is set in the masonry with flues under and around it heated by a
fire at the side. Close to the fire is a chimney, to which the products
of combustion are led from the flues by an underground channel.
There is also a direct passage into this chimney from the fire, and this
passage as well as that into the flues of the bath is provided with a
damper, so that according as the one or the other is more or less opened
or closed the temperature of the bath can be varied.
The cover of the bath is made in several parts hinged, so that they
can be separately opened to give access to the receptacle of the tempered
glass, or to the crust or scum receptacle, or to the skimming rake, and

page_text: in a fixed portion of the cover is a thermometer, which indicates the
temperature of the bath. There may also be a pipe for leading to the
chimney vapours evolved from the bath, and at the bottom of the bath
there is a pipe with a stop-cock or valve for emptying the bath.
The grating on which the glass plates are received may have rollers,
under which the glass slides, and by having these rollers heavier towards
the farther or lower end of the grating the velocity of the glass may be
gradually diminished before it reaches the end of its descent.
For tempering glass articles of forms other than flat sheets I arrange
the furnace and bath in the following manner:-The sole on which the
articles are placed to be heated is mounted by arms on an axis worked
by an external lever. In its horizontal position this sole covers over
the top of the bath, which is moreover closed by a sliding plate under
the sole. When the articles are heated sufficiently they are moved by
a rake on to a narrow lateral sole which is fixed on a level with the
moveable sole; the latter is then canted to one side, so as to expose the
mouth of the bath, and the sliding plate being then withdrawn
the heated articles are pushed into the bath. To prevent them from
striking the sides there are fixed in the bath pieces of wire gauze
inclining downwards towards the middle, which is open, forming a sort
of funnel, by which the glass articles are guided down towards the
middle opening. Near the bottom of the bath an endless web of wire
gauze is mounted on rollers and guided by narrow rollers along its
edges, and bars are fixed at intervals across it. The glass articles are
received upon this web, and when it is moved they are carried by it
upwards in a sloping direction and finally discharged from it at one end
of the bath into a receptacle made with a rounded bottom, in which
receptacle there is suspended a wire gauze basket which receives them,
and by means of which they are lifted out of the bath. Immediately
under the sliding plate which covers the opening into the bath below
the moveable slab is mounted a wire gauze rake, by which the crust and
scum is withdrawn from the surface of the bath before plunging the
glass articles into it. This rake is worked by an external handle on its
spindle, and the sole is moved by an external treadle, which is con-
nected by ratchet gearing to one of the rollers of the endless web, so
that every time the sole is moved the web is made to advance.
•
1

page_text: instead of the fixed bath which I have described for tempering sheets.
In employing such a moveable bath, which is a flat rectangular vessel
containing a grating and having one end to open, I mount it by
trunnions on arms near the mouth of the furnace, and adjust it to such
an inclination as to coincide with that of the sole when it is canted; I
then open the end of the bath, and canting the sole towards it cause
the articles to slide from the sole into the bath, which I then close and
remove, replacing it by another of the same kind.
For tempering cylindrical articles such as lamp glasses I employ an
apparatus which consists of a long spindle, on which the glass is placed
between two cones or between a cone and a collar. This spindle is
fitted by a feather to slide through, but revolve with a pinion, which
can be caused by gearing to revolve with considerable velocity, and the
pinion and its gearing are mounted by an arm on a horizontal axis. In
one position of this arm the spindle is horizontal, or nearly so, and cau
be slid with the glass on it through an opening into the furnace, where
being caused to revolve the glass becomes uniformly heated; the arm
is then moved into an inclined attitude, whereby the end of the spindle
with the glass on it is canted down into a bath below the furnace
chamber.
The end of the spindle may be fitted with sleeves or collars of
refractory material to suit glasses of different forms, or may carry a
hollow cylinder of pipeclay or other refractory material, within which a
glass tube or other cylindrical piece can be placed, and out of which it
is dropped into the bath when the spindle is canted.
Tongs of various forms may also be employed to hold between their
jaws the glasses to be tempered while they are being heated, so that on
opening the jaws they drop into the bath, and when such tongs are
employed I make them with a third arm besides the two which work
the jaws, this arm having attached to it a ring, or parts of a ring, by
moving which the glass is separated from the jaws when it happens to
adhere thereto.
Small articles, such as dishes, cups, and the like may be heated in
refractory moulds, so as to avoid spoiling their shapes, and plunged by

page_text: Fig. 1, Pl. 1, represents a side view; Fig. 2, Pl. 1, a longitudinal
section; and Fig. 3, Pl. 1, a sectional plan of my improved furnace,
bath, and apparaius for tempering flat sheets of glass..
A is a side compartment of considerable length, having mounted on
rollers within it a travelling metallic web a, on which are placed in
succession the sheets to be treated. The last of the rollers a' is worked
by a winch outside the wall. The compartment A. communicates with
the heating furnace C by a broad low side opening B, facing a hole b
in the outer wall. When a sheet has been brought by the web to face
the opening B, the attendant introduces through a flat fork, slightly
raises the sheet and pushes it through the hole B into the furnace where
it is heated to softening. The sheet lies upon a carriage c, which
consists of an iron framing c¹, having a facing of stone or other
refractory material level with the opening B, and the frame has rollers
running on a pair of small rails below, and a handle c³, by which it is
moved to and fro, so as to cause the sheet to be uniformly heated.
protect the lower part of the carriage and to economise heat, a refractory
arch or floor is formed a little below the table of the carriage, the stem
thereof passing down through a hole which is elongated to allow of the
to-and-fro movement of the carriage.
То
For the purpose of more uniformly heating the glass, the table of the
carriage might be made to rotate as well as to move to and fro by
constructing the carriage, as shown in Fig. 3, Pl. 3, where e is the
refractory table mounted by a vertical spindle on the carriage f, which
has its rollers running on the rails t. The handle which extends
through the wall of the furnace turns in a bracket bearing, having
collars on each side to prevent it from moving longitudinally, and is
connected by bevil gear to the spindle of e, so that by turning the
handle the table e can be rotated, and also by pulling or pushing i it
can be moved to and fro. In front of the compartment of the furnace C
which contains the moving table there is another compartment D,
which as well as C is heated from a fire F on the grate bars. This
fire-place is provided with an ash-pit door ſ, and a fire door ", in which
is a sight hole f³ for observing the state of the fire. The flames and
products of combustion passing over the bridge & heat the furnace and
escape by the opening B, heating the compartment A. The heat within

page_text: the furnace is regulated by a chimney G, which has a damper or cap
for adjusting the draught.
When the glass sheet is sufficiently heated on the table c², which can
be seen through the sight hole d¹, the carriage is pushed close up to the
oscillating sole E, which consists of a stone or other refractory table e
faced if desired with smooth porcelain, and resting on a framing e',
carried by two arms c, projecting upwards from a rocking shaft e³,
mounted near the bottom of the furnace and carrying a counter-
weight . Each of the arms e is made in two parts, the one sliding
along the other, with a screw and nut g by which the height and level
of the sole can be accurately adjusted. The lower part of the furnace h,
in which the rocking shaft e is mounted, is open in front and is covered
in by a plate through which are slotted holes for the arms e², and these
holes are covered by sliding plates through which the arms pass.
Thus
the flame is prevented from extending down to h, and also leakage of
cold air from into the furnace is avoided. The sole E being by partly
turning the rocking shaft brought to a level with the table c, the work-
man by means of a rake introduced through a side hole d² draws the sheet
of glass on to the sole, and then by means of a rake introduced through a
side hole d draws the sheet of glass on to the sole, and then by means of
an external lever I, fixed on the shaft e³, cants the sole towards the
mouth E of the bath J, as shown.in Fig. 2, Pl. 1. This movement of the
solc is limited by an adjustable stop on a quadrant along which the lever I
is moved. To prevent flame from entering the bath J from the furnace,
the mouth is closed by a vertical slide K suspended by a chain which
passes over guide pullies k, l, and is attached to the lower arm of the
lever I. When this lever is moved to cant the sole E into the mouth E¹,
the chain being at the same time pulled raises the slide K to allow for
the passage of the sole. When the sole is canted back to its horizontal
position where it rests against an iron bar, the chain is slacked out and
the slide K descends and closes the mouth of the bath. The sheet of glass
sliding from the inclined sole is received on a grating in the bath lying
at the same inclination. This grating rests on two side bars, 1, which
are pivotted at o' to the side frames 1, 1, fixed on a rocking shaft o; the
upper edge of the side frames rise a little above the face of the grating
to serve as side guides for the glass sheet, and their lower ends are tied
across by a piece of bent plate in which is placed a roll of wire gauze /
as an elastic buffer to receive the glass when it slides down.

page_text: The upper part of the grating for about one-fourth of its length has
losenge or diamond openings separated by bars sharp on their upper
edges, and for the rest of its length it consists of thin bars fixed at one end
to the points of the diamonds, and at the other end to a cross bar joining
the two side bars 1,, and projecting a little beyond them at each side, so
as to rest on the side frames 1, 1. A grating of the kind described gives
the liquid of the bath access to all parts of the glass. When it has
been immersed for the required time the grating L is canted back to its
level attitude by means of an external lever O fixed on the shaft o.
The lever O consists of two parts, the one part of fixed on the shaft, and
the other o sliding through guides on of and terminating in a claw,
which resting on a toothed segment p¹.holds the lever in any desired
position. On grasping the handle at the top of the lever (which handle
is made in halves, the one half fixed to o² and the other to o³) the claw
of o³ is released from the teeth of the segment, and the lever can be
moved. Adjustable stops p are provided to limit the throw of the lever.
The shaft o is at one end pivotted in the one side of the bath, and it
passes through the other side, having a cone fitting a conical seat, which
is kept tight against leakage by a spring pressing against the end of
the shaft. This spring also serves as a break to the movement of the
shaft, and its pressure can be adjusted by a screw . A counterweight
to balance the grating might be attached to the shaft o.
For light sheets the grating may be modified in the manner shown in
Fig. 1, Pl. 3, where rollers of wire gauze a are mounted so as to leave
room for the sheet to slide under them, while they bear with their
weight upon it, steadying it and retarding it in its descent. These rollers
are mounted on a separate framing, which when the grating is raised is
held up by an additional swing hook c. When the grating L has been by
the lever O raised to the horizontal position one of the projecting ends
of the cross bar at its lower end catches on a swing hook, which is
fixed on a spindle with an external handle, the weight of the handle
causing the hook to catch. The grating itself being thus held up the
side frames,, are lowered by means of the lever O till the buffer is
brought quite below the level of the grating. The workman then raises
the cover of the bath, and by means of a rake draws the glass sheet off
the grating into a shelved receptacle P. This done the frames 1, 1, are ·
again raised up to the grating, and the hook being disengaged, the
grating and frames are lowered to the inclined attitude. The recep-
B

page_text: tacle P, made of thin sheet metal, is divided by shelves so as to receive
a number of glass sheets. It is placed on a frame Q, which is fixed to
a rocking shaft p² mounted like the shaft o across the bath. On this
shaft is an external lever p³ with a catch engaging with a toothed
segment, so that the lever p³ can be moved and held in various attitudes
to bring the several compartments of the receptacle P in line with the
grating.
To remove scum or crust from the surface of the liquid in the bath a
skimmer is placed near the mouth E'. It consists of a blade worked by
an external handle 8, so as to push the scum along a curved plate into a
small wire gauze basket t, where it drains, the basket being taken out
and emptied when it has been filled up. The liquid is kept down to the
required level by a syphon overflow pipe u. The bath is suspended by
its upper flange on the walls of its setting, with flue space under and
around it. It is heated by the products of combustion from a fire T,
which after passing through the bath flues escape by a passage to the
chimney. From the fire T, besides the passage to the flues of the
bath governed by a damper , there is also a direct passage u² to
the chimney ', with a damper ³. By means of these dampers the
heat of the bath can be easily regulated.
The cover of the bath is made in several parts; the first part vis
hinged at to a fixed part a so that it can be raised as a door, and there
are two other doors and y', the one for access to the scum basket 4,
and the other for observing the adjustment of the sole E and grating L.
In the fixed part of the cover is placed a thermometer tube V,
preferably close to one side of the bath, and a pipe may be connected
from a to the chimney to carry off vapour; a cock y serves to empty
the bath.
The apparatus for tempering glass articles of various shapes is con-
structed on the same principles as that described, with such modifications
as are necessary to suit the articles treated.
Fig. 1, Pl. 2, represents a transverse, and Fig. 2, Pl. 2, a longitudinal
section; and Fig. 3, Pl. 2, is a sectional plan of a tempering oven for
articles such as wine glasses, tumblers, and the like. These, previously
heated in a separate stove, are introduced by the hole a' and placed
upon the sole B, which is of stone or refractory material laid on a frame b,
supported by two arms b², 62, on a rocking shaft C, having an arm and

page_text: counterpoise c and an external treadle D, by pressing down which the
sole can be canted to the position indicated by the dotted lines E, Fig. 1,
Pl. 3. When the sole is horizontal it covers the bath, and is level with
a shaft af at the side of the bridge a. When the articles on the sole are
properly heated they are moved by a rake on to the shelf a³, and then
by means of the treadle D the sole is canted over so as to uncover the
bath, whereupon the articles are pushed into the bath, and the sole is
returned to its horizontal position. As the sole does not form a perfectly
tight cover to the bath, a sliding plate f is arranged under it, the said
plate being withdrawn by an external handle at the time of plunging.
A wire gauze skimmer g is suspended by arms from a spindle g', having
an external handle g², and immediately before plunging the skimmer is
moved so as to sweep the scum or crust to one side. The handle g
might be connected to the treadle D, so that the skimmer should be
worked at the time the sole is canted over.
To prevent the glass articles from striking the sides of the bath a wire
gauze basket with sloping sides and open at bottom is suspended in
the bath, and its sides guide the glass on to the travelling wire gauze
web II. This web passes round rollers i, i, and is guided by short rollers.
at its edges to follow the form of the bath bottom. It has across it bars
of thin sheet metal, dividing it into lengths, one of which at each of its
intermittent movements is presented under the basket h to receive the
plunged glasses. These are carried by it upwards, and finally delivered
into a wire gauze basket hung by straps m in the well I of the bath.
The web His advanced a division every time the treadle D is moved, the
shaft c of the treadle being connected by ratchet and suitable multi-
plying gear to the roller of the web.
The heating of the oven and bath is effected by two fires in a manner
similar to that already described, and the bath is provided with a cover
having doors, thermometer, and other necessary fittings.
A pipe U having a flap door u may be fixed in the wall of the
furnace, from which its interior will receive heat for warming small
articles, such as lamp glasses, placed in the pipe before they are laid on
the sole B.
Fig. 2, Pl. 3, represents the mouth of an oven and a portable bath
which it is advantageous to use for special articles, such as mirror plates

page_text: or optical glasses. In front of the oven mouth is placed a jointed
framing c, provided with segments and clamping screws, so that it can
be adjusted in various attitudes and angles. The portable bath C con-
taining the liquid and a grating is heated separately, and placed on the
table c of the jointed framing, being adjusted in position thereon by a set
screw j. For plunging, the door k of bath is opened, the glass is slid
on to the grating from the sole B, the door is closed, and the bath is
removed to give place for another of the same kind.
Fig. 4, Pl. 3, represents part of the section of a bath with apparatus
for tempering lamp glasses or tubes generally; and Fig. 5, Pl. 3, is a
front view of the apparatus. A frame a is pivotted at b, and has a strong
pin d bearing on an arc c, giving friction sufficient to support the
frame in any attitude. On the frame a is mounted a drum K, which
can be turned by a winch handle m, and there is also mounted in two
bearings, supported from the frame a by a column e, a sleeve i, on
which is a small pulley bearing against the drum K, and driven from it
by frictional contact. Through the sleeve i slides a rod n, which may
be square in section or fitted with a feather, so that it must turn with i,
but can slide freely through it. On the one end of the rod » is swivelled
a ball handle by which the rod can be pulled or pushed while it revolves;
at the other end is a cone on which is placed the lamp glass. The work-
man pushes in the rod n, so that the glass enters a hole in the furnace
or a heated pipe like U, Fig. 2, Pl. 2, and turning the drum K causes
the glass to revolve rapidly, so as to become uniformly heated to the
required temperature; he then draws it back till it is over the bath, as
shewn in Fig. 4, Pl. 3, and raising the frame a causes the apparatus to
take the inclined attitude indicated by the dotted lines, the glass being
plunged into the bath.
Fig. 6, Pl. 3, and Fig. 7, Pl. 3, shew rods į, such as above referred
to, for holding glasses, either cylindrical, pear shaped, globular, or of
mund
Fig. 8, Pl. 3, is a side view, and Fig. 9, Pl. 3, a plan of tongs for lamp
glasses. a are the jaws of the tongs worked by the handles a',
is a ring embracing the glass and worked by an intermediate handle c,
a²; and b
3