AN IMPROVEMENT IN FURNACES
Year: 1834

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
CHANTER, of Earl Street, Blackfriars, in the City of London, and of Stamford
Street, in the County of Surrey, Gentleman, send greeting.
WHEREAS His present most Excellent Majesty King William the Fourth,
by His Letters Patent, under the Great Seal of Great Britain, bearing date
at Westminster, the Second day of September, in the fifth year of His reign,
did, for Himself, His heirs, and successors, give and grant unto me, the said
John Chanter, His especial licence that I, the said John Chanter, my exors,
admors, and assigns, or such others as I, the said John Chanter, my exors,
admors, 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 "AN IMPROVEMENT IN
FURNACES;" in which said Letters Patent is contained a proviso obliging me
the said John Chanter, by an instrument in writing under my hand and
seal, particularly to describe and ascertain the nature of my said Invention,
and in what manner the same is to be performed, and to cause the same to be
enrolled in His said Majesty's High Court of Chancery within six calendar
months next and immediately after the date of the said recited Letters Patent,
as in and by the same, reference being thereunto bad, will more fully and at

page_text: large appear; and whereas His late Majesty King George the Fourth, by His
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Tenth day of June, in the ninth year of His reign, did, for
Himself, His heirs and successors, give and grant unto Richard Witty, then
of the Township of Hanley, in the County of Stafford, Engineer, His especial
licence that he, the said Richard Witty, his exors, adiñiors, and assigns, or
such others as he or they 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 his Invention of
Certain Improvements in Apparatus for making and supplying Coal Gas for
Useful Purposes, within England, Wales, and the Town of Berwick upon
Tweed; and whereas the said Richard Witty, in and by a certain Specification
or instrument in writing under his hand and seal, bearing date the First day of
December, in the year of our Lord One thousand eight hundred and twenty-
eight, and enrolled in His Majesty's High Court of Chancery on the Fifth
day of December aforesaid, did, in pursuance of a proviso for that purpose in
the said last-mentioned Letters Patent contained, particularly describe and
ascertain the nature of his said Invention, and in what manner the same was
to be performed, as by reference to the said Letters Patent and Specification
respectively being had will more fully and at large appear; and whereas the
said Richard Witty has assigned the said last-mentioned Patent, and all benefit
and advantage thereof to me, the said John Chanter, my exors, adiñiors, and
assigns.
NOW KNOW YE, that in compliance with the proviso contained in the
said first recited Letters Patent, I, the said John Chanter, do hereby declare
that the nature of my said Invention of An Improvement in Furnaces
consists of an improvement of so much of the said Invention of the said
Richard Witty as applied to the making and supplying of gas from coal for
the purpose of heat, in the method of construction, the adaptation, and
arrangement of the parts, and the formation, as herein-after described, of an
additional distilling plane, by which means I render the said Invention of the
said Richard Witty applicable to steam-boat boilers, and increase the utility of
such Invention when applied to the boilers of fixed steam engines or to hot
water apparatus and various other useful purposes; and in further compliance
with the said proviso, I, the said John Chanter, do hereby describe the manner
in which my said Invention is to be performed by the following statement
thereof, reference being had to the Drawings annexed, and to the figures and
letters marked thereon, that is to say:-

page_text: In the annexed Drawing, Fig. 1, A represents the longitudinal section of a
steam-boat boiler with improved furnace applied thereto.
H is a hopper
or reservoir for the coal intended to supply the furnace, and from which the
coal descends to the feedemouth B. This hopper is placed immediately con-
tiguous to the boiler, in order that the coal therein contained may be partially
dried by the heat of the boiler, and it has a strong grating a near the top
to regulate the size of the coal admitted; the bars of this grating are placed at
the distance of three inches or thereabouts apart, and the coal which is too
large to pass through must be broken. At the lower part of the hopper H is
a roller with several cavities which serves to regulate the supply of coals to
the feedmouth B. This roller turns in the direction marked by the arrow
upon it, and may be worked by hand or may be put in motion by the power of
the engine, in which case a horizontal shaft with a drum fixed on it with the
requisite gear will be required. These parts it will be unnecessary for me to
describe, as they can be applied by any common millwright or engine maker.
The velocity must be regulated according to the power of the engine and the
quality of the coal, but in general it must be such as to supply about 10 lbs. of
coal per horse power per hour. On the roller at e is fixed a crank, which by
means of the connecting rod r gives motion to the presser P, which has one
or more projecting rods in front at t, which enter the coal and prevent it
binding into too hard a mass. The alternate motion of the presser P, which is a
shallow iron box on rollers with a rack placed inside, produces the required effect
of opening and advancing the coal on the distilling plane. This distilling plane
E is so constructed as to form part of the boiler, being rivetted from side to
side of the usual watercourses between the furnaces and itself, forming a water-
course through the furnace from one side of the boiler to the other. In front
of this watercourse E, at f, is an opening or man-hole covered with a plate of
metal screwed tight, and which can be removed when required to clear out
any sediment which may be deposited in such watercourse. The upper surface
of the watercourse E, on which the coal rests, will heat the coal to about
200 degrees, which will not only dry it and prepare it for combustion, but will
also cause the gas to be given out with less heat and greater facility. The
upper surface of the coal on the distilling plane E, is subjected to intense heat,
and is continually giving off a large portion of gas, which is inflamed with
heated air, as shall be hereafter explained. G is a watercourse constructed in
a similar manner to the additional watercourse or distilling plane E, and
forming a check or stop to reverberate the heat. F. F, F, are fire clay lumps

page_text: or tiles resting on ledges formed for that purpose in the boiler, which
reverberate and radiate heat on the surface of the coals on the distilling
plane E.
The fire-clay lumps or tiles also assist by radiating and reverberating the heat
in the extrication and inflammation of the gas, and causing the perfect union
of the carbon of the gasses with the oxygen of the air admitted through the ignited
coke on the grate bars M, M, M. L is a plate of iron extending from the grate
bars M, M, M, to the door O. The iron plate Liforms a second distilling plane,
and is supplied with coal through the door O. M, M, M, are the grate bars, which
are to be completely covered with coke supplied from the distilling planes E and
L. The coke is regulated and spread over the bars by the firemen or stokers,
who for that purpose introduce an iron rod or slice through the door O. When
it is required to remove the clinker or slag it is forced by an iron rod along the
bars to the horizontal opening T, which is provided with a sliding plate X,
having a long handle v, v. When this slide is withdrawn the clinker or slag
will fall into the ash pit U; the slide is then to be replaced. D is the door of
the ash pit U, and is furnished with a register or sliding plate to regulate the
quantity of air passing through the bars M, M, M. V is the bridge of the
boiler, and I prefer forming this part of fire clay lumps when my improved
furnace is applied to new boilers, but when applied to old boilers or those of
common construction the water bridge which they generally have will do.
S, S, are the flues of the boiler. The proportions of the grate bars to produce
the required heat will be about one quarter less than the bars generally used,
the more perfect combustion of the coal on the distilling planes producing an
addition to the heat equal to the reduction of the bars. By the hopper in
front the coal is gradually dried and warmed before it arrives at the distilling
plane E, where it is further heated prior to the gas being extracted. The
steam which would prevent the perfect inflammation of the gasses, as well as
reduce the temperature, is thus exhaled, and from the introduction of air
heated to from one thousand five hundred to two thousand degrees of heat by
its passage through the ignited coke on the bars of the furnace, the heated
gasses evolved from the coal produce the most perfect combustion; from the
high temperature maintained there will be a most complete and perfect
inflammation of all the volative products of the coal, and more heat will be
produced from a given weight or quantity that can be done by the furnaces
commonly used; the nuisance of smoke will be in a great measure prevented,
and the fires will maintain a more regular and abundant supply of steam, an
object of great importance to the regular working of the engines. Fig. 2
represents the application of my improved furnace to the boiler of a fixed

page_text: steam engine. The description of the hopper H, with its feedmouth and
presser, having been before stated in describing Fig. 1, and the same letters
referring to the same parts, it need not be again repeated here. E is a distil-
ling plane formed by the construction of an additional boiler, which is
connected with and kept continually supplied with water from the main boiler
by two pipes or channels s and h. The pipe or channel h enters the lower
part of the additional boiler E at the side at a, and the same pipe or channel
enters the main boiler A at the side at v. The pipe or channels enters the
upper part of the additional boiler at the side at w, and also enters the side of
the main boiler at m. When the furnace is in action a continued circulation
of water from the main boiler A will take place through the additional
boiler E. In front of the boiler E, at f, is an opening covered with a plate of
metal screwed tight, and which can be removed when required to clear out any
sediment which may be deposited in the additional boiler E. By means of this
additional boiler an extra supply of steam can be given, and the coal on its
upper surface will be dried and heated, which will cause the gas to be given
out more readily. F, F, is an arch of fire clay lumps or bricks, from which
heat is radiated and reverberated on the surface of the coal on the distilling
plane E. This radiation and reverberation of heat on the coal causes it to
give out its gas, which is inflamed with heated air arising through the
bars M, M. G, G, are fire clay lumps or bricks placed in a vertical position,
and forming a check or stop to prevent the escape and reverberate the heat
into the furnace. An iron plate is placed at the back of these lumps or
bricks in order to render them more durable. L is a plate of iron extending
from the grate bars M, M, to the door O. Through this door the fireman or
stokers regulate the coke on the bars and remoke the clinker or slag. V, V, are
the flues of the boiler; U, the ash pit. D is the door of the ash pit, and it is
furnished with a register or sliding plate to regulate the quantity of air passing
through the bars M, M. The use of my improved furnace when applied to fixed
steam engine boilers or other apparatus where the same may be applicable
will be attended with the same beneficial results and advantages as before
stated in describing its application to steam-boat boilers.
Now whereas I have above described and ascertained the nature of my said
Invention of an improvement in furnaces, and in what manner the same is to
be performed, I hereby claim as my Invention the use of an additional
distilling plane by the application of the watercourse E in steam-boat boilers,
and of the additional boiler E, when applied to the boilers of fixed steam
engines, with the connecting pipes or channels and h, and the improved
arrangement of part; described by the above statement and the Drawings

page_text: thereby referred to; and I do not claim originality or exclusive right by virtue
of the said Letters Patent granted to me as aforesaid of, in, or to any other of
the parts herein-before described.
In witness whereof, I, the said Johu Chanter, have hercunto set my
hand and seal, this Twenty-fifth day of February, in the year of our
Lord One thousand eight hundred and thirty-five.
AND BE IT REMEMBERED, that on the Twenty-fifth day of February,
in the year of our Lord 1835, the aforesaid John Chanter came before our
said Lord the King in His Chancery, and acknowledged the Specification
aforesaid, and all and everything 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.
Inrolled the Second day of March, in the year of our Lord One thousand
eight hundred and thirty-five.