AN IMPROVEMENT IN THE MANUFACTURE OF GLASS
Year: 1854

page_text: LETTERS PATENT to Auguste Edouard Loradoux Bellford, of 16, Castle
Street, Holborn (City), London, Patent Agent, for the Invention of
"AN IMPROVEMENT IN THE MANUFACTURE OF GLASS."-A communication.
Sealed the 26th May 1854, and dated the 12th January 1854.
PROVISIONAL SPECIFICATION left by the said Auguste Edouard Loradoux
Bellford at the Office of the Commissioners of Patents, with his Petition,
on the 12th January 1854.
I, AUGUSTE EDOUARD LORADOUX BELLFORD, of 16, Castle Street, Holborn
(City), London, Patent Agent, do hereby declare the nature of the said
Invention for "AN IMPROVEMENT IN THE MANUFACTURE OF GLASS" to be as
follows:-
The employment of a furnace with fire chambers on the outside, so arranged
as to generate combustible gases by forcing a current of air through a thick
stratum of ignited fuel, and with arrangements for admitting such gases to
the furnace with a blast or blasts of air to cause a rapid combination of the
oxygen of the air with the gases, & thus cause their perfect combustion.
The furnace is of the usual construction, but instead of having the fire grates
nearly on a level with the bottom of the trough, it has two fire chambers
outside, whose grates are sunk to a depth of from three to five feet below the
top of the sieges, to contain a deep stratum of fuel. The fire chambers com-
municate with the furnace through flues, & are supplied with fuel through
hoppers. Air to produce necessary combustion is supplied by a blower, through
a pipe having branches leading to the ash-pits & to the flues, and carried, for
the purpose of heating the air, through heating chambers, into which heat passes

page_text: from the furnace. The air admitted through the pipes into the ash-pit is
driven through the grates, & causes the combustion of the lower portion of
the stratum of fuel upon the grate bars. The gases generated by the com-
bustion are conveyed (together with heated air) into the furnace, where their
combustion is immediately ellected in a most perfect degree. The heat thus
produced is applied to the bottoms of the pots, & diffuses itself round about
them previously to striking the crown of the furnace, thus preventing tears, &
at the same time making the bottom of the pots as hot as the top, which is
very essential to the making of good glass.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Auguste Edouard Loradoux Bellford in the Great Seal
Patent Office on the 12th July 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, 1, AUGUSTE
EDOUARD LORADOUX BELLFORD, of 16, Castle Street, Holborn (City), London,
Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twelfth day of January, in the year of our Lord One
thousand eight hundred and fifty-four, in the seventeenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Auguste Edouard Loradoux Bellford, Her special license that I, the said
Auguste Edouard Loradoux Bellford, my executors, administrators, and assigns,
or such others as I, the said Auguste Edouard Loradoux Bellford, my execu-
tors, 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 "AN IMPROVEMENT IN THE MANUFACTURE OF GLASS,"
upon the condition (amongst others) that I, the said Auguste Edouard
Loradoux Bellford, 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 I, the said Auguste Edouard Loradoux Bellford,
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, that is to say:-

page_text: In the ordinary glass furnace, which depends for the supply of air necessary
for the combustion of the fuel upon the draught created by a cone, or the
openings of the working holes, a very great portion of the fuel is lost by the
escape of the combustible gases unconsumed; and in consequence of the layer
of fuel on the grate being very thin, a considerable quantity of atmospheric
air passes undecomposed through the fire grate into the furnace, and is often
the cause of the breaking of the pots, and consequent heavy loss to the
manufacturer. The frequent cleaning of the cinder from the grate bars during
the process of melting retards the operation, and often causes the metal to be
"seedy," and thus depreciates its quality and value. The fire is commonly
placed near the sieges, and has a tendency to cut or melt away the sieges from
under the pots, and thus cause a great loss of pots and glass. The tendency
of the flame from the fire, as commonly arranged, is to strike against the
cap or crown of the furnace, and thereby cause "tears" or "drops," which
fall into the pots, and thereby cause great loss to the manufacturers. The same
difficulties are attendant in a greater or less degree upon the employment
of those furnaces which are worked with blast, and the attention of manufac-
turers has been long devoted to the discovery of some means of obviating them.
The object of this Invention is to prosecute the manufacture of glass in such
a way as to avoid all the above difficulties. The Invention consists in the
employment, as herein-after described, of a furnace with fire chambers on the
outside, so constructed and arranged as to generate combustible gases by
forcing a current of air through a thick stratum of ignited fuel, and with
certain arrangements for admitting such gases to the furnace with a blast or
blasts of air in such a way as to cause a rapid and intimate combination of
the oxygen of the air with the gases, and thus cause their perfect and imme-
diate combustion, and produce an intense degree of heat.
The accompanying Drawing illustrates the manufacture of glass, according
to my Invention, representing a furnace in which it may be performed.
Fig. 1 is a longitudinal vertical section of the furnace; Fig. 2 is a trans-
verse vertical section; and Fig. 3 is a plan.
Similar letters of reference indicate corresponding parts in the several Figs.
The furnace is of well-known construction, being made with an arched top
A, and having parallel sieges B, B, to support the pots C, C, and being pro-
vided with the usual working holes a, a, and foot holes b, b. But instead of
having the fire grates nearly on a level with the bottom of the trough c, between
the sieges, it has two fire chambers D, D, outside, whose grates are sunk to a
depth of from three (3) to five (5) feet below the top of the sieges, in order to
contain a deep stratum of fuel. The depth of the fire chambers will require

page_text: When
If the
to be less or greater, according as the coal is more or less bituminous.
a caking coal is used, the depth should be not less than three (3) feet.
coal used burns freely, the depth may be four (4) feet; but for coke or
anthracite coal a depth not less than five (5) feet will be found most advan-
tageous. The fire chambers communicate with the furnace through flues d, d,
and are supplied with fuel. through. hoppers e, e. They are intended to be
kept constantly filled, which may be accomplished by keeping the hoppers
filled or covered by a heap of coal, which will sink as the lower part of the
stratum burns away. The ash pits E, E, are closed by air-tight doors f, f.
The air which is supplied to the fire chambers to produce the necessary
combustion of the fuel, and to generate the combustible gas, and to cause the
combustion of the said gases in the furnace, is supplied by a blower of any
suitable construction, through a pipe F; which has branches G, G, and H, H,
the former leading to the ash-pits, and the latter leading to the flues d, d.
The branch pipes II, II, are carried, for the purpose of heating the air, through
heating chambers I, I, into which a portion of the heated contents of the
furnace escape through small passages g, g, and from the bottom of the said
heating chambers they run across the ends of the furnace, as shown in Fig. 3,
and discharge the air into the flucs d, d, through a number of small nozzles h, h,
in a number of small streams. The supply of air through the pipes G, G, is
regulated by valves" i, i, and the supply through H, H, by valves j, j. The
temperature of the heating chambers I, I, is regulated by dampers J, J, at
the top.
The air admitted through the pipes G, G, into the ashi-pit, is driven through
the grates, and causes the combustion of the lower portion of the stratum of
fuel upon the grate bars. The greater portion of the gas resulting from this
combustion will be a combustible gas, namely, carbonic oxide, which is always
produced during the process of combustion, when the temperature is very high,
and the proportion of carbon is in excess to that oxygen. The carbonic
acid gas which is produced by this combustion of the lower portion of the fuel
will, in passing through the mass of ignited fuel above, which is at a red heat,
take up an additional charge of carbon, and thus be converted into carbonic
oxide. At the same time the carbonaceous gases contained in the fuel, such
as carburetted or bicarburetted hydrogen, will be evolved or distilled from the
coal by the heat. Hence all that is combustible of the fuel in the fire chambers
is 'converted intò combustible gases, which will pass into the flues d, d, where
they are met by the streams of heated air issuing from the nozzles h, h, and
driven with the air into the furnace, where their combustion is immediately
effected in a most perfect degree. The heat thus produced is applied to the

page_text: bottom of the pots, and diffuses itself round about them previously to striking
the crown of the furnace, thus preventing tears, and at the same time making
the bottom of the pots as hot as the top, which is very essential to the making
of good glass. No dust or undecomposed carbonaceous matter is allowed to
come in contact with the glass, to darken its color and injure its quality. The
supply of air through the pipes G, G, and H, H, is regulated by the valves so
as to produce the most perfect combustion of the gases, and by regulating the
generation and combustion of the gases the heat may be regulated and kept
uniform from the commencement of the melt till the glass is fine. The glass
which is split while filling the pots, or through pots breaking, is caught in the
trough of the furnace, and not blackened, and can be laded out, and made into
rough plate glass, or thrown into water to be used again as cullet in the pots,
or it may be allowed to run from the furnace through a small hole made for
that purpose.
The Invention is applicable to the manufacture of window glass, green
glass, flint glass, and plate glass, and also to blowing furnaces, annealing kilns,
and flattening kilns or ovens. In all cases the general construction of the
furnace or kiln is the same as that of those now in use, the Invention relating
only to the construction and arrangement of the fire chambers and treatment
of the fuel. The filling of the pots or other manipulations of the workmen are
conducted according to the method now generally adopted.
It may be well to observe, that cold air, instead of heated air, may be forced
through the nozzles h, h, to mingle with the gases generated in the fire
chambers; but it is far preferable to employ heated air, as above described.
I claim the manufacture of glass in a furnace, in which the heat is produced
by the combustion of gases, which are generated in a chamber or chambers
outside the furnace, by forcing a current of air through a thick stratum of
ignited fuel, and are conducted into the furnace by a flue, through which a
blast of air is forced with them into the furnace, substantially as herein
described.
In witness whereof, I, the said Auguste Edouard Loradoux Bellford,
have hereunto set my hand and seal, this First day of July, in the
year of our Lord One thousand eight hundred and fifty-four.
A. E. LORADOUX BELLFORD. (L.S.)