IMPROVEMENTS IN FURNACES USED IN THE MANUFACTURE OF GLASS.
Year: 1874

page_text: LETTERS PATENT to William McAdam, of Glasgow, in the County
of Lanark, North Britain, for the Invention of "IMPROVEMENTS IN
FURNACES USED IN THE MANUFACTURE OF GLASS.'

page_text: The object of the present improvements is to prevent or diminish the
tendency of the bridge forming the ends of the tank, and over which the
flames from the fire-grates pass into the tank, from oxidizing, burning,
or wearing away as rapidly as they do if constructed solid. This object
has been effected hitherto by the use of an air channel or space in or
through the bridge.
According to the present Invention hollows or recesses are formed in
the bridge in which a water tank or vessel is situated and provided with
a bail-cock or equivalent means for regulating the supply of water
thereto. The heat imparted to the bridge is taken up by the water and
the hot water is utilized for heating purposes, the bridge being thereby
prevented from becoming unduly heated and rendered more durable.
By placing in the hollows or recesses a vessel capable of withstanding
pressure and provided with a safety valve this arrangement may be used
for generating steam for motive or analogous purposes.
In place of using a water vessel or boiler, as herein-before described,
the hollow spaces in the bridge are filled with a non-conducting sub-
stance, such as asbestos or amianthus, steatite or soapstone, charcoal, or
others having analogous properties.
In place of constructing the bridges as herein-before described,
with through channels or spaces, and filled or not with water vessels or
boilers, or with non-conducting material, such spaces may be divided by
one or more cross partitions, one such partition being preferably
employed.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
.
filed by the said William M'Adam in the Great Scal Patent Office
on the 22nd May 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
MADAM, of Glasgow, in the County of Lanark, North Britain, Glass
Bottle Manufacturer, send grecting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fourth day of November, in the year
of our Lord One thousand eight hundred and seventy-four, in the

page_text: .
"
Under a modification of my said Invention, instead of constructing
the bridges with enclosed channels or spaces and filling such spaces
with water tanks or vessels or steam boilers, or with non-conducting
substances, as herein-before set forth, the spaces may be divided by one
or more cross partitions (one such partition being preferably employed).
And in order that my said Invention may be properly understood I
'now proceed more particularly to set forth the system, mode, or manner,
in or under which the same is or may be used or practically carried into
effect, reference being had to the annexed Sheet of Drawings, and to
the letters and figures marked thereon, that is to say :—
On the Sheet of Drawings hereunto appended Figure 1 is a vertical
section of that portion of a tank glass melting furnace embracing the
melting tank and fire-grates; Figure 2 is a horizontal section of the
furnace on the line a, b, Figure 1. As shewn by these Figures the
bridge A between each end of the tank B and its fire-grate C, is con-
structed with a hollow space or recess whose length may be either equal
to or greater than the breadth of the fire-grates C. In each of the
hollow spaces or recesses a water tank or vessel D is situated and pro-
vided with a pipe a and ball-cock or valve E, or equivalent means for
regulating the supply of water to the tanks or vessels D. The pipes a
and ball-cocks or valves E communicate with tanks or cisterns F, and by
means of this arrangement, as the water contained in the tanks or
vessels D is evaporated by the heat extracted from the bridges A and
passes off in the form of steam or vapour through the pipes b, Figure 2, or
through equivalent exits, the falling of the balls attached to the spindles
of the cocks or valves E, opens the cocks or valves and allows water to
pass from the cisterns F into the tanks or vessels D, so that a constant
level of water is maintained therein. Instead of steam or vapour only
passing outwards from the tanks or vessels D through the pipes b, the
water heated by the heat extracted from the bridges A may also pass
outwards through the said pipes or through other equivalent exits and
be utilized for heating purposes, the bridges being thereby prevented
from becoming unduly heated and rendered more durable. By placing
in the hollows or recesses (in the position occupied by the tanks or
vessels D) a vessel or boiler capable of withstanding pressure and pro-
vided with a safety valve, the arrangement of bridges, shewn at Figures
1 and 2 of the Drawings, may be used for generating steam for motive

page_text: power or analogous purposes. In lieu however of using a water vessel
or steam boiler the hollow spaces in the bridges A may be filled with a
non-conducting substance, such as asbestos, or amianthus, steatite, or
soapstone, or charcoal.
Under another arrangement instead of constructing the bridges with
enclosed hollow spaces or recesses filled with water vessels or boilers, or
with a non-conducting material, as hercin-before described, the spaces in
the bridges may be left open at their lower ends whereat they commu-
nicate with the space or cave beneath the melting tank and fire-grates,.
as shewn in vertical section at Figure 3 of the Drawings. Under this
arrangement the spaces A are divided vertically by one or more parti-
tions, one such partition being preferably employed, as shown at B,
Figure 4 of the Drawings, which is a horizontal section of the melting
tank and fire-grates on the line c, d, Figure 3. A cooling or refrigerating
current of atmospheric air passes upwards into the spaces A on each
side of the partition B, and circulating through the said spaces takes up
the heat imparted to the bridges by the flames and products of com-
bustion passing from the fire-grates C, by which means the bridges are
cooled or prevented from becoming unduly heated, and are thereby
rendered more durable. In place of the current of refrigerating air
passing upwards from the cave below, the ends of the bridge may be
left open to the atmosphere for the admission of air.
Having now described and particularly ascertained the nature of my
said Invention, and the system, mode, or manner, in or under which the
same is or may be used or practically carried into effect, I would observe
in conclusion that what I consider to be novel and original, and there-
fore claim as the Invention secured to me by the herein-before in part
recited Letters Patent is,
First. The use or employment of water vessels or steam boilers, or of
non-conducting substances, for the purposes set forth, in the bridges of
tank furnaces used in the manufacture of glass, substantially as herein-
before described and in part illustrated at Figures 1 and 2 of the Drawings
hereunto appended.
Second. Arranging and constructing the bridges of tank furnaces
employed in the manufacture of glass with hollow spaces open at their
lower ends or sides and divided by one or more vertical partitions, sub-

page_text: stantially as herein-before described, and in part shewn at Figures .3
and 4 of the appended Drawings.
In witness whereof, I, the said William M'Adam, have hereunto
set my hand and seal, this Twenty-first day of May, One thousand
eight hundred and seventy-five.
WILLIAM MCADAM. (L.S.)