IMPROVEMENTS IN THE MANUFACTURE OF GLASS
Year: 1838

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
HARTLEY, of Bishop Wearmouth, in the County of Durham, Glass Manu-
facturer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the First day of December, in the second year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said James
Hartley, Her especial license, full power, sole privilege and authority, that I,
the said James Hartley, my exors, admors, and assigns, or such others as I,
the said James Hartley, my exors, adññiors, or assigns, should at any time
agree with, and no others, from time to time and at all times during the term
of years therein expressed, should and lawfully might make, use, exercise,
and vend, within England, Wales, and the Town of Berwick-upon-Tweed,
my Invention of "IMPROVEMENTS IN THE MANUFACTURE OF GLASS;" in which
said Letters Patent is contained a proviso, that I, the said James Hartley,
shall cause a particular description of the nature of my said Invention, and in
what manner the same is to be performed, to be inrolled in Her said Majesty's
High Court of Chancery, within six calendar months next and immediately
after the date of the said in part recited Letters Patent, as in and by the
same, reference being thereunto hail, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
James Hartley, do hereby declare the nature of my said Invention, and the
manner in which the same is to be performed, are fully described and ascer-
tained in and by the following statement thereof, reference being had to the

page_text: Drawings hereunto annexed, and to the figures and letters marked thereon
(that is to say):-
:-
My Invention relates to the manufacture of that description of glass called
spread or broad glass; and in order to give the best information in my power
I will, in the first place, shortly state the mode of manufacturing such descrip-
tion of glass heretofore practised, and then proceed to explain the improve-
ments invented by me. In making spread or broad glass as heretofore
practised, the workman blows a cylinder or cone which is split lengthwise
when hot, and becomes a flat sheet, or is opened out by means of heat, the
splitting or cutting being performed by placing the cylinder or cone in the
spreading furnace till it nearly collapses. It is then drawn out into the open
air, and by a drop of water placed at one end cracks or slits from one end to
the other, as is well understood; and owing to the Excise laws in respect to
broad or spread glass, the operation of splitting or cutting must be performed
before cooling down after it is blown, and the annealing arch or furnace is
only allowed to have one opening or mouth; and by the old means of con-
veying broad glass from the flatting furnace, the glass must be very highly
heated to permit of its being carried through the air. Owing to such Excise
laws, any improvement in the manufacture of spread or broad glass must bo
such as to be capable of being performed in conformity with such laws, and
according to the means heretofore resorted to. The bottom of the spreading
or flatting furnace is convex, in order that when the glass is becoming flat by
the force of heat that no air may be below it; and it is well known that if the
glass were to remain quiet during such spreading operation the glass would
bend over the convex surface, and be of every irregular figure, to prevent
which the workman, during the process of spreading or flatting, turns the
sheet round whilst in a highly heated state on the convex bed of the furnace,
and thus brings each portion of the edge thereof towards the fire, and permits
the same to become more heated, and by care and judgment he so moves the
sheet of glass on the convex bed as to obtain the same into a flat or plane
surface. He then immediately withdraws it from the furnace on to a flat
iron table at the mouth of the spreading furnace, at which time the glass is
in a highly heated state, which, as before stated, is necessary to prevent the
breaking of the glass on its being carried through and exposed to the open
atmosphere from the spreading furnace, in order to be placed in the annealing
furnace or arch, which carrying is performed by a fork called a "fushet;" and
it is well known that owing to the process of spreading by moving the glass
on the convex bed of the furnace in the highly heated state (suitable to
produce the flatting or spreading, and to its being subsequently carried

page_text: through, and exposed to the atmosphere,) materially injures the surface of
the glass.
Now, according to my Invention the cylinder or cone is cut or slit by an
improved process. It is spread by pressure on a flat surface or bed, kept atra
lower temperature than those heretofore used, and it is conveyed to the an-
nealing arch or oven by means of a heated table or surface, which runs on
wheels, moved and guided by a suitable railway. I consequently obviate the
necessity of having a convex bed, and dispense with the turning or revolving
movement of the glass, so prejudicial when in a highly heated state, which is
necessary according to the old process to get it into a level sheet by the force
of heat on a convex bed; and further, owing to the mode of carrying from the:
spreading furnace to the annealing arch or oven, I am enabled to dispense
with the necessity of heating the glass so highly as heretofore by the heat of
the table or surface on which the glass is carried preventing the prejudicial
chill or action of the atmosphere.
Having thus generally pointed out the nature of the old processes resorted
to, and the nature of the bed of the furnace used, and the prejudicial effects
consequent thereon, and having also shortly referred to the peculiarities of the
processes when performed according to my Invention, I will now proceed
more particularly to describe my improvements.
DESCRIPTION OF THE DRAWING.
Figure 1 shows an elevation of a spreading or flatting furnace, in section
arranged according to my Invention, together with three annealing arches
or ovens of the ordinary construction. Figure 2 is a plan of Figure 1, the
same being shown in section, in order to the internal arrangements being
readily understood; Figures 3 and 4 showing elevations of the two end views.
of the spreading furnace. In each of these Figures the same letters indicate-
similar parts; a, a', being the spreading furnace which, is divided into two
compartments by the wall or partition a³, there being an opening from the
compartment a into the compartment a' through the wall a², as is shown in the
Drawing. b, b, are two sets of fire bars, on which fires are kept constantly
burning, and I prefer the same to be of wood instead of coal. c is the
spreading table or bed of the furnace, which is flat, and I prefer the same to
be of sandstone, such as is obtained from Godstone, in the County of Surrey,
but I do not confine myself thereto. d is an opening through which the
cylinder or cone is to be placed into the spreading furnace, in order to its being.
heated, from whence it is removed to the table or flat bed c, to be spread
by pressure, as hereafter explained. e is an opening through which the

page_text: workman inserts the instrument for spreading the cylinder or cone into a flat
sheet of glass. f is the opening through which the sheet of glass, when
opened out, is slided from the table or bed c on to the bed or table g, in the
compartment a¹ of the spreading furnace or oven; and it will be seen that the
table g is carried by a frame of iron on wheels which run on a railway, as is
shewn in the Drawing, the fronts of the annealing arches being built
parallel with the railway; hence the table g brings the sheets of glass up close
to the mouths of the annealing arch or furnace, all which will readily be
understood on an examination of the Drawing, and it will readily be understood
that the table or surface g, (which is made of similar material to the table or
bed c,) will be kept heated by being brought into the compartment of the
spreading furnace a', and the workman having stopped the bed g opposite any
one of the annealing arches, he, by means of the "fushet," removes the sheet
of glass from the table g, and places it into the annealing arch, in like manner
to that heretofore practised.
Having thus described the nature of the furnace employed for spreading the
glass, and also the machinery and apparatus for carrying the sheets of glass
from the spreading furnace to the annealing arches, I would remark that I
make no claim to that part of the process of making broad or spread glass,
which relates to the producing cylinders or cones, up to that part of the process
where the same is to be cut. The cylinders or convex are to be made as hereto-
fore practised, but I prefer that class of good and skillful workmen who can
produce the most perfect cylinders; nor do I claim the annealing arches or
ovens, or the process of annealing, that being similar to what have been
before practised and used; and my Invention commences with that part of the
process which relates to cutting or splitting of the cylinder longitudinally, and
I perform that operation by means of a bar of iron, which being heated red-
hot, I pass or rub from end to end of the cylinder of glass two or three times,
having some charcoal or other carbonaceous matter between the heated iron
bar and the cylinder, by which means the glass will be split or cut.
The split
cylinder or cone being placed on the flat table of the spreading furnace, I
proceed to flat or spread out the same into a sheet by pressing the same on
the flat bed by means of a small block of wood affixed on an iron bar. The
description of wood I employ for flatting the glass is alder, well soaked in
water, but I do not confine myself thereto; and I would remark in respect
to the temperature at which the broad or spread glass is preferably spread,
according to my Invention, is such that the operation may be performed in a
minute. With this information a workman, with very little practice, will
readily perform my Invention. The workman having flatted or spread a

page_text: cylinder or cone into a sheet of glass, he pushes it through the wall a², on to
the table or surface g, by which it is conveyed to one of the annealing arches,
as above explained.
Having thus described the nature of my Invention, both as to the processes
and also as to the furnace machinery and apparatus employed, I would have it
understood that what I claim is, first, the mode of splitting cylinders or cones
of glass, as above described.
Secondly, I claim the mode and furnace employed for flatting or spreading
broad or spread glass, by means of pressure on a flat bed, as herein
described.
And, thirdly, I claim the mode of carrying broad or spread glass from the
flatting furnace, as herein described.
In witness whereof, I, the said James Hartley, have hereunto set my
hand and seal, this Twenty-third day of May, One thousand eight
hundred and thirty-nine.
Signed, sealed, and delivered by the within-
named James Hartley, (being first duly
stamped.) in the presence of
JAMES (t.s.) HARTLEY.
AND BE IT REMEMBERED, that on the Twenty-third day of May, in the
year of our Lord 1839, the aforesaid James Hartley came before our said
Lady the Queen in Her Chancery, and acknowledged the Specification afore-
said, and all and every thing therein contained and specified, in form above
written. And also the Specification aforesaid was stamped according to the
tenor of the Statute made for that purpose.