IMPROVEMENTS IN SMOKE-CONSUMING APPARATUS
Year: 1868

page_text: LETTERS PATENT to Dillwyn Smith, of Burlington, New Jersey,
United States of America, now of No. 8, Southampton Buildings,
Chancery Lane, in the County of Middlesex, Gentleman, for the
Sealed the 26th February 1868, and dated the 27th August 1868.
PROVISIONAL SPECIFICATION left by the said Dillwyn Smith at
the Office of the Commissioners of Patents, with his Petition, on
the 27th August 1868.
I, DILLWYN SMITH, of Burlington, New Jersey, United States of
America, now of No. 8, Southampton Buildings, Chancery Lane, in
the County of Middlesex, Gentleman, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN SMOKE-CONSUMING APPARATUS," to
be as follows:-
My Invention relates to a simple, cheap, and convenient method of
providing the furnaces of steam boilers and other furnaces with appa-
ratus for burning smoke and other products arising from the combustion

page_text: of the fuel, and one of the objects of the said Invention is to so construct
such an apparatus that the same may be applied to any furnace or fire-
grate without disturbing the brickwork or any other part of the structure.
Hitherto the application of any smoke-consuming apparatus to furnaces
has been attended with so much inconvenience and the beneficial effect
produced by such apparatus has been so slight that the general use of
means for consuming the smoke in such furnaces has been prevented,
and the ill effects arising from the escape of smoke and other products
of combustion, and the waste arising from the imperfect combustion of
the fuel are still very great.
My improved apparatus is so constructed that it can be readily adapted
to a furnace of any size, and can be applied to the furnace of a steam
engine or other furnace of a factory or workshop without disturbing the
structure, or without hindering the work carried on in such factory.
In the construction of my apparatus two horizontal bars, each in one
or more pieces, are made to rest upon the existing dead plates which
support the ordinary furnace bars. These two bars are made rather deeper
than such furnace bars and extend the entire length of the furnace.
The said horizontal bars support a number of cross bars formed and
arranged with apertures or spaces between them for the admission of
air, or these cross bars may be made hollow to admit air through them.
The cross bars are made of any suitable shape, but I prefer to make
them of a triangular or V form with feet resting upon the two horizontal
bars. I prefer that these cross bars should be made singly or separately,
but if desired a number of them may be cast together. The said bars
may be made of cast iron or of fire-clay, plumbago, or other fire-resisting
material. When made of iron I prefer to make them of a section
resembling that of ordinary fire-bars, that is, broad on the surface
exposed to the fire and narrow at the other edge. The upper part or
apex of these triangular bars and the feet are made thicker than the
other parts of the bar, or otherwise suitably formed to keep the central
parts of the bar forming the principal air passages slightly apart. Inside
these cross bars on each of the sloping sides I prefer to arrange per-
forated plates. These plates are preferably formed of two sheets or plates
of sheet iron perforated with small holes fixed on a frame with a space
between them. The said plates extend from end to end of the series of
cross bars, and prevent any danger of displacing the said bars in raking
the fire or introducing fuel into the furnace. If the perforated plates

page_text: should become clogged or choked with ashes or fine cinders they can
he readily drawn out endwise from the apparatus and freed from the
obstructive particles by shaking or other like simple means..
It will be readily understood from the foregoing description of my
apparatus that the air enters the same from the ash-pit through the open
space between the longitudinal bars, and is thence uniformly distributed
through the series of cross bars and perforated plates into the fuel
throughout the entire length of the furnace. In some cases however
I admit it at one or both ends of the series of cross bars. To ensure a
more perfect uniformity in the supply of air to all parts of the furnace I
provide the apparatus with draw plates, which are fitted to slide in
grooves or upon shoulders extending lengthwise along the interior
surfaces of the vertical part of the longitudinal bars, and are formed
at the end with flanges whereby the mouth of the ash-pit may be
entirely closed if desired. I prefer to employ three of these plates
arranged one below the other. The first plate is placed a short distance
below the top of the bars and is made to extend about one-third the
length of the furnace; the air admitted above this plate enters the front
part of the furnace. The second plate extends about two-thirds the
length of the furnace, and air is admitted between this and the first plate
to the intermediate part of the furnace. The third plate is extended to
the end or back of the furnace, and air is conducted to the same between
this and the second plate. By adjusting the plates the supply of air to
any part of the furnace may be increased or diminished at pleasure, or
such supply may be entirely stopped by pushing the plates so far inward
that their flanges close the aperture at the front of the ash-pit.
In applying my improved apparatus to a furnace after having ascer
tained the proper length of the horizontal bars, that is, the length
between the existing dead plates in the furnace, I make the said bars
0 of that length, I have then only to remove a few of the fire-bars from
the central part of the grate and place my apparatus in the space
previously occupied by such bars; the apparatus may be conveniently
It is therefore obvious that no
introduced through the furnace doors.
part of the structure need be disturbed or injured, and that it will not
5 be necessary to let the furnace cool. Thus the loss of time, expense,
and other inconveniences usually attending the application of any addi-
tional apparatus to a furnace or boiler is entirely avoided, the combustion
of fuel in the said furnace is improved, and the nuisance arising from

page_text: the escape of smoke is entirely prevented. Instead of arranging the cross
bars and perforated plates in the centre of the furnace the same may be
arranged at one or both sides of the said furnace. I sometimes use
perforated hollow bars or tubes which may be placed in the centre of
the furnace instead of the two horizontal bars.
་
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Dillwyn Smith in the Great Seal Patent Office
on the 27th February 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DILLWYN
SMITH, of Burlington, New Jersey, United States of America, now of
No. 8, Southampton Buildings, Chancery Lane, in the County of
Middlesex, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-seventh day of August, in the
year of our Lord One thousand eight hundred and sixty-eight, in the
thirty-second year of Her reign, did, for Herself, Her heirs and succes-
sors, give and grant unto me, the said Dillwyn Smith, Her special
licence that I, the said Dillwyn Smith, my executors, administrators,
and assigns, or such others as I, the said Dillwyn Smith, 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 SMOKE-
CONSUMING APPARATUS," upon the condition (amongst others) that I, the
said Dillwyn Smith, my executors or administrators, by an instrument
in writing under my, or their, or one of their hands and seals, 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 Dillwyn Smith, 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

page_text: following statement, reference being had to the accompanying Drawings,
forming a part of this Specification :-
My Invention relates to a simple, cheap, and convenient method of
providing the furnaces of steam boilers and other furnaces with apparatus
for effecting the more thorough combustion of both the solid and gaseous
portions of the fuel, the objects of the said Invention being to prevent
the escape of smoke and other products of combustion, and to so construct
such an apparatus that the same may be applied to any furnace or fire-
grate without disturbing the brickwork or any other part of the structure.
Hitherto the application of what is ordinarily termed smoke-consuming
apparatus to furnaces has been attended with great inconvenience without
producing the desired beneficial result, consequently the ill effects arising
from the escape of smoke and unconsumed gases and the waste arising
from the imperfect combustion of the fuel are still very great.
My improved apparatus is so constructed that it can be readily adapted
to a furnace of any size, and can be applied to the furnace of a steam
engine or other furnace in a factory or workshop without disturbing the
structure and without greatly bindering the work carried on in such
factory.
In the construction of my apparatus two horizontal or longitudinal
bars, each in one or more pieces, are made to rest upon the existing dead
plates which support the ordinary furnace bars; these two bars extend
the entire length. of the furnace, and are preferably made rather deeper
than such furnace bars. The said longitudinal bars support a number
of cross bars formed and arranged with apertures or spaces between or
through them for the admission of air. The cross bars are made of any
suitable shape, but I prefer to make them nearly of a U or V form, and
to arrange them in an inverted position or with their feet or wide portion'
resting upon the two longitudinal bars. I prefer that these cross bars
should be made singly or separately, but if desired a number of them
may be cast together. The said bars may be made of cast iron or of fire-
clay, plumbago, or other fire-resisting material. Inside these cross bars
I prefer to arrange perforated screens which are preferably formed of two
sheets or plates of sheet iron perforated with small holes and fixed on a
frame with a space between them. The said screens extend from' end' to
end of the series of cross bars; they aid in heating and more evenly
distributing the air which passes through the apparatus, and also preveüt
any danger of displacing the said bars in raking the fire or introducing!

page_text: fuel into the furnace. If the perforated plates should become clogged or
choked with ashes or fine cinders they can be readily drawn out endwise
from the apparatus and freed from the obstructive particles by shaking
or other like simple means. To ensure a more perfect uniformity in the
supply of air to all parts of the furnace I may provide the apparatus with
draw plates which are fitted to slide in grooves or upon shoulders
extending lengthwise along the interior surfaces of the vertical part of the
longitudinal bars, and are formed at the end with flanges whereby the
mouth of the apparatus may be entirely closed if desired. I prefer to
employ three of these plates arranged one below the other and of
different lengths so that they will admit air to different parts of the
furnace.
As my Invention is more especially designed to be employed in the
furnaces of boilers which are formed with internal flues or tubes I have
in the accompanying Drawings shown it in connection with such a boiler,
and I will now proceed more fully to describe the said Invention.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a longitudinal central section of part of a Cornish boiler
shewing the furnace thereof fitted with my improved apparatus; Figure 2
is a transverse section on the line x, x, Figure 1; Figure 3 is an exterior
end view of the said furnace; Figure 4 illustrates a modification of
part of my Invention; Figures 5, 6, 7, 8, and 9 are detached views
drawn to an enlarged scale illustrating the construction of the small
transverse bars which form the most essential feature of the said apparatus.
Like letters indicate the same parts throughout the Drawings.
A is the internal flue or tube of the boiler, and B is the external shell
of the same. The dead plates C and the fire-bars D may be formed in
any ordinary and convenient manner. The horizontal or longitudinal
bars a, as shewn in Figures 2 and 4, are preferably inserted in the centre
of the furnace, their upper surface being level with the top of the bars D.
The said bars with the plates 6 and bottom plate 6' extend from the
front of the boiler to the back plate c, and thus separate the space d
enclosed between them from the ash-pits d'. The small transverse or cross
bars e, which are preferably of cast iron, may be made sectionally like
the ordinary longitudinal fire-bars, that is to say, they may be broad on the
surface exposed to the fire and narrow on the inner edge, and they may
be made with their feet thicker than the intermediate portion, so as to

page_text: admit the air through the spaces between the said intermediate portions.
I however prefer to use bars constructed in the manner illustrated in
Figures 5, 6, 7, 8, and 9, as I find them cheap and convenient to manu-
facture and efficient and durable in use. As shewn in Figure 6 the
bars e have their sides parallel and are arranged with the surfaces of all
of the bars in contact with each other throughout the series. At the
sides of these bars I cast the recesses e, and when two of the bars are
arranged together the recesses of the two adjacent sides of the bars form the
holes for the passage of the air, which thus passes in a series of small jets or
currents from the space fenclosed within the bars e into the fuel and the
space just above the same, where it is mingled with the combustible
gases. The bars e being in contact with the burning fuel in the furnace
are necessarily kept at a very elevated temperature, and it is obvious that
in its passage through the space fand through or between the bars e the
air by coming in contact with the said bars and other parts of the
apparatus must acquire a temperature greatly above the ordinary tem-
perature of the atmosphere or what is termed cold air, and that therefore
it will not practically lower the temperature of the furnace or require to
absorb a large quantity of heat to raise it to the degree of temperature
required to produce its combustion or the combination of its particles of
oxygen either with the solid carbon or the gases eliminated from the
burning fuel. I prefer to make the holes or apertures e conical or taper,
as shewn in Figures 5 and 7. I also prefer to make these bars with the
outer surfaces es bevilled or reduced to an edge so that the coal lies
against a series of ridges between which the air holes open into the
spaces or channels es. The front end of the series of bars e is closed by
the plate or block e. I find it advantageous to connect the feet e¹ of
the transverse bars by a cross piece et, as this piece prevents the bending
inward or contraction of the bars e caused by the unequal heating of
their inner and outer edges. I may however construct the bars without
the cross pieces e*. These cross pieces, when used, form a convenient
means for supporting the perforated screens g, which, as shown in
Figure 5, may be inserted inside the series of bars e. These screens are
formed by securing the thin perforated metal plates or sheets g¹ upon
the frame g, a space equal to the thickness of the said frame being left
between the perforated plates..

page_text: placed just below the bars D, and is made to extend rather more than a
third of the length of the furnace, as shown in Figure 1. The air
admitted above this plate enters the front part of the central space
enclosed within the bars e. The second plate i extends about two-thirds
of the length of the furnace, and the air is admitted between this and
the first plate to the intermediate part of the said central space.
The third platej is extended to the end or back of the air passage below
the furnace, and air is conducted between this plate and the plate i to
the rear portion of the central space. By adjusting the plates h, i,
and the supply of air to any part of the furnace through the cross
bars e may be increased or diminished at pleasure, or such supply may
be entirely stopped by pushing the plates so far inward that their
flanges h¹, ¹, and j', close the front aperture of the air passage or space d.
It will not be necessary in many cases to use these draw plates, as
the admission of the air may be regulated by means of a door or
cover placed over the front aperture of the passage d, as shewn in
Figure 3. Instead of forming the central air passage between the
vertical plates 6 fitted in the grooves 6' in the bars a, as shewn in
Figure 2, I sometimes form the passage, as shewn in Figure 4, between
the adjustable plates 6, which are hinged or jointed to the bars a, and
can be extended or spread apart to increase the area of the said air
passage as required.
In applying my improved apparatus to a furnace, after having ascer-
tained the proper length for the horizontal bars, that is, the length
between the existing dead plates in the furnace, I make the said bars of
that length. I have then only to remove a few of the fire-bars D from
the central or other convenient part of the grate and place my appa-
ratus in the space previously occupied by such bars. The apparatus
may be conveniently introduced through any ordinary furnace doors.
It is therefore obvious that no part of the structure. need be disturbed
or injured, and that it will not be necessary to stop the working of the
boiler for a longer time than is necessary for the furnace to cool suffi-
ciently to allow the workman to enter the furnace, and in some cases
even this stoppage may not be absolutely necessary. Thus the loss of
time, expence, and other inconveniences usually attending the application
of any additional apparatus to a furnace or boiler is entirely avoided, the
combustion of the fuel in the said furnace is improved, and the nuisance
arising from the escape of the smoke is prevented.

page_text: Instead of arranging the cross bars and perforated plates in the centre
of the furnace the same may be arranged at one or both sides of the
said furnace, the cross bars being then made in the form of straight or
curved pieces, and arranged to rest against the sides of the furnace or
against plates or blocks inserted therein. The cross bars e may be made
in the form of hollow tubes, or instead of using bars arranged to enclose
a space between them, I may employ in the place thereof a series of
transverse plates, either solid or hollow, with spaces between them for
the admission of the air.
I sometimes use hollow perforated bars or tubes, which may be placed
in the centre or other convenient part of the furnace instead of the two
horizontal bars a. I may also vary my apparatus by placing two or
more sets of the horizontal bars and cross bars in a furnace.
In some
cases I admit air at one or both ends of the series of cross bars. The
admission of air to the ash-pits d' and grate bars D is regulated by the
doors, which are hinged or otherwise attached to the front of the boiler,
as seen in Figure 3.
It will be readily understood from the foregoing description of my
apparatus that the air which enters the same through the air passage d
is admitted in the furnace in a number of small jets or streams, and is
thereby uniformly distributed and mixed with the solid fuel and gases.
I am thus enabled by the use of a simple and durable apparatus to
approach nearer than has hitherto been practicable to the desired result
of furnishing an adequate supply of oxygen to the hottest part of the
furnace in such a manner as to effect the perfect combustion of the
carbonaceous and gaseous particles of the fuel therein.
I am aware that mixing air with the fuel and combustible gases of a
furnace by admitting the air in small jets or currents is not new, but
the apparatus heretofore employed for that purpose has not been con-
structed in such a manner as to endure for any length of time the
intense heat to which it is subjected when placed at the centre of the
furnace. Moreover such apparatus has not been heretofore provided
with means for restricting the admission of the air thereto, having been
used merely as means for augmenting the supply of air while the main
portion of the same was still allowed to pass through the grate bars.
Now having thus fully described my said Invention, and shown how
the same may be conveniently and advantageously carried into practice,
I wish it understood that as above stated I do not claim as my

page_text: Invention the method of distributing the air amongst the solid and
gaseous contents of the furnace in small jets or streams; but I
claim,―
First. The small transverse bars constructed in any convenient
form and of any suitable material, and arranged in the centre or other
convenient part of the furnace in such a manner as to admit the air
thereto in small jets or streams for the purpose set forth.
Second. Constructing these transverse bars in such a manner that
when placed together in the furnace they form a central passage or
compartment from which the air is distributed between the said bars
or through small apertures formed therein, substantially as set forth.
Third. The perforated screens arranged in combination with the
bars e, substantially as and for the purpose set forth.
Fourth. The central air passage d extending from end to end of the
ash-pits, and provided with means for regulating the admission of air to
the small cross bars e, substantially as set forth.
Fifth. The draw plates for regulating the admission of the air to the
small cross bars e formed and arranged within the central air passage d,
substantially as set forth.
Sixth. The horizontal bars a and small cross bars e combined and
arranged together and with the central air passage d, and with or
without the perforated screens g, substantially as and for the purpose
set forth.
In witness whereof, I, the said Dillwyn Smith, have hereunto set
my hand and scal, this Twenty-third day of February, in the
voor of our Lord One thousand eight hundred and sixty-nine.