CERTAIN IMPROVE- MENTS IN THE MEANS OF ECONOMIZING FUEL, AND IN THE APPARATUS EMPLOYED THEREFOR
Year: 1873

page_text: LETTERS PATENT to Philip Henry Williams, of Swansea, in the
County of Glamorgan, for the Invention of "CERTAIN IMPROVE-
MENTS IN THE MEANS OF ECONOMIZING FUEL, AND IN THE APPARATUS EMPLOYED
THEREFOR.
"
Sealed the 11th November 1873, and dated the 15th May 1873.
PROVISIONAL SPECIFICATION left by the said Philip Henry Williams
at the Office of the Commissioners of Patents, with his Petition,
on the 15th May 1873.
I, PHILIP HENRY WILLIAMS, of Swansea, in the County of Glamorgan,
½ do hereby declare the nature of my said Invention for "CERTAIN Improve-
MENTS IN THE MEANS OF ECONOMIZING FUEL, AND IN THE APPARATUS EMPLOYED
THEREFOR," to be as follows:-
The Invention relates more particularly to those classes of furnaces
employed in heating water and other substances for the generation of
steam or other gas for motive power purposes, or for other general
purposes, whereby heat radiating from or conducted by the exterior

page_text: surfaces of such furnaces or parts adjacent thereto, deriving heat from
the same or from exhausted vapour generated by such furnace, and
now thrown off as waste heat can be utilized for the
purpose of supply-
ing the furnace generating such heat with hot air in lieu of cold, these
improvements being accompanied in some cases by a contrivance for
jets of steam to facilitate the draught, and the consumption of the
combustible gases evolved from the fuel.
As an example I will describe the application of the improvements,
first in connection with locomotive, marine, or stationary boilers; and
secondly, in connection with furnaces or fires employed for domestic
purposes. In the former of these applications, viz., to the locomotive
or marine boiler which must be taken as an example for other boilers or
furnaces in connection with other motive power engines, I proceed as
follows: When dealing more particularly with the locomotive boiler,
I construct in connection with the exhaust and blast pipe of the same,
an arrangement of pipes and annular spaces in connection with the
smoke box and funnel, both combined and communicating with each
other in such a manner that the opening or entrance for air into such
spaces or pipes will be at a point in or near to the external portion of
the funnel or other convenient place, into which the air will enter and
circulate through such annular spaces or tubes around and about the
thoroughfares through which the waste heat from the furnace and
exhaust steam from the cylinders escape. The heat thrown off in these
passages will be received into the outer air spaces or tubes encircling the
same, so that the current of air passing along and through such outer
spaces will receive the heat therefrom and so become effectually heated,
(and then either after passing through a receiver or in a more direct
manner), it is forced or conveyed and drawn by the furnace or forced by
other means along thoroughfares or pipes into the fire or through channels
placed near to and between the lagging and the boiler, which will main-
tain or still further intensify the heat of such air up to the time of its
arrival at the point of discharge into the furnace where it becomes diffused
below and above the bars of the same, so as to feed the fire with air at a
high temperature, the nature of which readily ignites the gases evolved
from the fuel, effecting thereby a most rapid and thorough combustion of
the same. In order to effect if possible more thoroughly the combustion of
these gases evolved from the fuel, all other entrances for the admission of
air are closed, allowing thereby the hot air alone created by the waste heat

page_text: of the furnace to be the only agent of combustion that is admitted to
the furnace. Or in some cases an aperture may be formed for the
admission of cold air or a jet of steam, which if superheated materially
assists the hot air in creating by an effectual combustion of the gases an
intense heat within the furnace.
The novel construction and adaptation of one or more hot air passages
when applied to stationary boilers is arranged in such a manner that
the heated gases escaping from the furnace will impinge against and
heat the same, so that the air passing through such thoroughfares into
the closed ash-pit of the furnace will receive during such passage an
amount of heat, which when escaping through and above the bars will
materially assist in the rapid and effective combustion of the gases
evolved from the fuel.
For domestic purposes there would be many ways of applying the
principle of these improvements, for instance in an ordinary kitchener,
cooking, or heating stove, or apparatus, the fire-place and ash-pit of which
would be closed so as to prevent the admission of cold air, the hot air
passages or pipes supplying the fire with the heated air or gases of
.combustion would be so disposed about the flues, ovens, and hot water
spaces of the same, and arranged in such a manner that the air drawn
into and through such pipes or passage by the fire at a distance
remote therefrom, would become during its transmission to the closed
ash-pit and fire of such kitchener, cooking, or other heating apparatus
thoroughly heated, in which state it would be drawn into the fire so as
to supply the same with hot in lieu of cold air, the effect of which
would be to more thoroughly consume the gases evolved from the fuel,
producing at the same time greater heat, thereby materially cconomizing
the consumption of fuel.
In ordinary domestic fire-places employed for the purpose of warming
the hot air may be formed in a space immediately behind the back
plate of the grate and at the sides thereof, the heat passing into this
space and which is now absorbed by the bricks would be utilized in the
generation of hot air which may be passed direct into the rooms so as
to diffuse heat, or it may be passed into the fire under the bars, in both
of which cases it will assist in creating a superior heat from a less
quantity of fuel than the same amount used in the ordinary manner
would be capable of doing. It will be evident that the air used for thus

page_text: economizing fuel may be heated in separate stoves of fire-places provided
for that purpose in addition to and even in some cases in lieu of the
contrivances herein-before mentioned.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Philip Henry Williams in the Great Seal Patent
Office on the 15th November 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, PHILIP
HENRY WILLIAMS, of Swansea, in the County of Glamorgan, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifteenth day of May, in the year of our
Lord One thousand eight hundred and seventy-three, in the thirty-sixth
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Philip Henry Williams, Her special licence that
I, the said Philip Henry Williams, my executors, administrators, and:
assigns, or such others as I, the said Philip Henry Williams, 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 "CERTAIN IMPROVE-
MENTS IN THE MEANS OF ECONOMIZING FUEL, AND IN THE APPARATUS EMPLOYED
THEREFOR," upon the condition (amongst others) that I, the said Philip
Henry Williams, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should par-
ticularly 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 Philip Henry Williams, 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

page_text: by the following statement and accompanying Drawings, that is to
say :-
The Invention relates more particularly to those classes of furnace
employed for heating water and other substances for the generation of
steam or other gas when designed as a medium for giving motion to
motive power engines or for manufacturing or other general purposes.
The solid fuel employed in such furnaces which will be more particularly
suitable for serving the object of this Invention would be coal, lignite,
peat, or other similar carbonaceous matter that has not been previously
decomposed in separate apparatus.
The object of the Invention is the economy of fuel and the effecting
of a thorough combustion of the gases and obtaining more intense heat
in such furnace by the employment of radiating heat as herein-after
described through the medium of a novel arrangement of parts, whereby
such heat is conducted along the exterior or interior surface of the
furnaces or generating media or parts adjacent thereto deriving heat
from the same or from exhausted vapour generated by such furnaces,
the whole of which, according to the present construction of engines
and generators, has hitherto been thrown off as waste heat.
Under the present Invention the waste heat can be utilized for the
purpose of supplying the furnace with hot air or hot blast in lieu of
cold and more particularly for supplying highly heated air or other
supporter of combustion to the gases passing from the solid fuel during
decomposition.
These improvements in some instances are supplied with auxiliary
means for increasing the draught and power of the engine or generator
to which they may be applied, and consist in adapting thercto contri-
vances for infusing hydrogen or other gases or jets of steam into the
current of hot air supplying the furnace.
In order that the Invention may be clearly understood in detail I
have hereunto annexed three Sheets of Drawings, on which as examples,
various applications of this Invention are shewn as applied to the furnaces
of locomotive, marine, and stationery boilers, and to furnaces for other
purposes, the whole of which are designed with the sole object of econo-
mizing fuel by the utilization of waste heat.
Sheet 1 is devoted to the locomotive engine and boiler, in which Fig. 1
represents a longitudinal section of a locomotive boiler, having applied

page_text: thereto the arrangements of parts designed for collecting the waste heat
and passing it on to the furnace.
Fig. 2 represents an end view of the same, one half being shewn in
section.
Fig. 3 ropresents another longitudinal section of a locomotive boiler
in which the exhaust or funnel.is shewn in position over the fire-box.
Fig. 4 represents an end elevation and part section of the smoke box
end of a locomotive, the funnel of which is supplied with a cowl; and
Fig. 5 represents a detached vertical section of the same.
In these Figures a, a, is the shell of the boiler; b, the jacket or saddle;
c, c, the openings or passages into which cold air is received; d, d, d,
the pipe or pipes conveying the cold air to the surfaces where it will
become rarified by the heat thrown off from such surfaces; e, the pipes
or passages conveying the heated air along the side of the boiler, or
through the jacket or saddle c to the outer space g about and underneath
the fire-box f; h, h¹, h, are openings from such outer space g of the
fire-box f, through which the air now in a highly heated state issues
into the furnace, and which in this state is the only gas of combustion
admitted thereto; i is a damper excluding the outer atmosphere from
the space g around the fire-box, but which can be opened if desired to
admit cold air; k, k, are cowls for collecting the cold air; and is
the exhaust.
In order that the various parts herein referred to shall be clearly
understood, together with their arrangement and the manner in which
such parts collect and convey hot air or blast, and in some instances air
impregnated with hydrocarbon to the furnace, I will proceed to describe
the same, having reference to the Drawings. Taking, for example, an
ordinary locomotive to which these improvements are adapted, and
which slightly altered or modified will equally apply to portable and
other locomotive and agricultural engines, I proceed as follows:-I
place inside the chimney a¹ a number of tubes d (vide Fig. 1) radiating
around the centre thereof at sufficient distance apart to allow or permit
the waste gases or heat to circulate between them and at the same time
leave sufficient space up the centre for the exhaust. Any section of
tube for this purpose may be employed, but the section I prefer is
eliptical or of a form that will present a great amount of heating surface.
The opening into these tubes d for the entrance of air is at a point outside

page_text: the chimney plate. The said tubes are provided with a chamber b' in
which the air as it is received therein freely circulates. In order to
create a rush or blast of air I fit round the outer portion of this chamber
on the chimney plate one or more cowls provided with hanging and self-
acting valves c¹ in order that in whatever direction the engine may be
going one series of valves will, with the rush of air against them, open
and admit air, the other valves at the opposite side being at the same
time closed. The air on passing through these valves c¹ rushes down
the pipes c into another larger tube or chamber c² situate on each side
of the smoke box o through which it travels to the fire-box f. These
heating tubes c and c² are made larger at their lower end than at the
top in order to allow for the expansion of the air. At the base of the
chimney these pipes c are caused to pass downward on either side of
the smoke box so as not to interfere with the cleaning of the boiler
tubes. By this arrangement and disposition of the tubes c and c³ they
absorb heat in the smoke box, which being transmitted to the current of
air passing through them causes such air in a highly heated state to be
passed into the outer tubes, from whence it becomes distributed and
injected into the furnace.
In order to accelerate the speed or current of air along the outer
tubes towards its exit into the furnace I employ a jet of steam
obtained by preference from the exhaust. Further to prevent any
cooling of the air in these hot air passages c, c², I line or coat the same
with a refractory substance plastered on when setting, or the pipes them-
selves may be composed of a non-radiating material. In some cases
such heating pipes may be made of a section similar to that shewn in
the Drawing at Fig. 5, so that they will lic in a position near the shell
of the boiler and between it and the lagging, so as to be entirely pro-
tected and covered thereby. The sides of the smoke box, chimney, and
other places where it is desired to prevent the radiation of heat may also
be covered over or coated with a refractory substance if it should be
found advantageous.
In order to intensify the heating properties of the air feeding the
furnace with the means of combustion I provide the heating pipe c¹
with an opening or passage into another pipe communicating direct with
the furnace. The entrance of such pipe thereto is in the side plates
on a line with the baffle plate, or it may be situated in any other con-
venient position. This supplementary pipe is provided with openings at

page_text: a point between its junction with the pipe c¹ and its termination
in the furnace plate. Through these openings absorbent material
strands of cotton wick or the like are inserted so as loosely to fill at
such points the interior of the said pipe. This absorbent material
or these strands outside the pipe are immersed in petroleum or other
hydrocarbon spirit or oil, which being conveyed by capillary attraction
into the interior of the supplementary pipe causes the hot air passing
through the same in its onward course to the furnace to become im-
pregnated with hydrocarbon or other fluid contained in the absorbent
material, thereby converting such heated air into carbonic oxide or other
gas, which through the application of a damper or valve I cause to pass
as required into the smoke box. The hot blast in the pipe c² at the
point of its exit is received into a chamber or space g encompassing the
sides of the fire-box, in which space the air passes down the sides
thereof, to a place which now according to the present construction of
locomotive engines is the entrance to the furnace for cold air or blast
underneath the fire-bars. For this purpose I remove the present damper
in part further back or dispense with it altogether, and keep the back
damper closed, so as to prevent the entrance of cold air only on occasions
when it may be required. The hot blast which passes into the space
around the fire-box above the engine frame and fire-bars I use to supply
one or more tubes which communicate and pass inside from one side
to the other. These tubes inside the furnace space are perforated so
that the hot air shall issue from them in a series of jets or thin shcots,
and in such a manner that the gases evolved from the fuel shall of
necessity be brought intimately into contact with the gases evolved from
the fuel or other supporter of combustion, thereby effectually completing
their consumption or conversion into carbonic oxide gas.
I prefer to arrange or so dispose the perforated tubes from which the
hot air issues in such a manner that one will take its position immediately
over the stoke hole, and the other immediately over the edge of or
underneath the bridge against the back of the fire, cold air never being
allowed an entrance into the fire-box above the fire-bars.
I do not wish to confine myself to the foregoing mode of utilizing
waste heat as in the description following another modification and
example for heating air and conveying it to the furnace is set forth, and
which will be readily understood on reference to Figs. 3, 4, and 5.

page_text: In the construction of apparatus or thoroughfares designed for
absorbing the waste heat and carrying it to the furnace according to
the following arrangement, I place the chimney of the locomotive or
other similar engine on the fire-box end of the boiler, and construct in
connection therewith two flues which communicate direct with the
smoke box. These flues in form are similar to the jacket or saddle
tank of a locomotive, along the centre of which I carry the exhaust
pipes from the cylinder or through the boiler to the blast pipe in the
chimney funnel. Along these flues the waste heat is drawn by the
exhaust. They also contain tubes c similar to those herein-before
described, and into which air is passed from a chamber provided with
cowls similar to the arrangement before mentioned, or a chamber may
be placed over the smoke box provided with entrance valves for cold
air, which when received in such chamber pass direct into parallel
pipes (Fig. 2) suitably situated so as to absorb heat. But in order
to prevent radiation or loss of heat I cause the air before entering these
pipes to circulate in a space formed between the smoke box and an
outer covering with which it is provided.
In the case of saddle tank engines the flues may be arranged to pass
through the saddle containing the water, or where the weight will
permit I form a chamber on the boiler similar to a saddle tank divided
by a midfeather so as to form two flues or spaces which I fill in with
bricks, tiles, or perforated slabs, made specially to combine lightness,
stability, and durability. These blocks, slabs, or bricks being retainers
of heat transmit to the air passing through the flue in which they are
placed a very high temperature. The air can by an arrangement of
dampers be passed alternately through those flues to the space around
the fire-box from whence it passes into the furnace in a manner similar
to that already described. In this arrangement the exhaust pipe
may pass through the said flues or direct through the boiler to the
chimney.
Having thus given a description of the application of my Invention
to locomotive engines I will proceed to describe the peculiarity of its
arrangement and adaptation to stationary and marine boilers, the
illustrations of which are shewn on Sheet 2.
Fig. 6 represents in longitudinal section that portion of the flue of the
furnace situated between the bailar and the chimnov stoak.
Ti 17

page_text: represents a plan section of the same; and Fig. 8 a transverse section
through the line x, x, of Fig. 6. In these views it will be seen that the
space A in the flue between the boiler and the chimney stack is consider-
ably enlarged. This space is divided longitudinally by a partition or
wall B, thus forming two distinct or separate passages or thoroughfares
C, C. The entrance to and exit from these passages are provided with
dampers D, D, which will enable such thoroughfares to be alternately
opened and closed as desired. The whole of the interior space of these
thoroughfares is filled in with firc-stone, brick, or other raw or manu-
factured material in such a manner that openings or interstices will be
formed. These chambers are provided in the rear with openings and
dampers E, E, which may also be furnished with a cowl by which the
admission of cold air to the said chamber or space can be regulated and
through which the air so passing in its onward course coming in contact
with the hot slabs, bricks, or tiles with which such chambers are filled
will receive a very high temperature, in which state it passes through
metal pipes or other tubes to the furnace where it becomes the only
medium for supplying the fire with the gases of combustion. The
dampers are so arranged that they will allow the heated gases passing
from the furnace to the chimney alternately to rush first through onc
chamber for the purpose of heating the bricks contained therein, then
through the other. Simultaneously the cold air passes through the
chambers in a reverse direction isolated from the flue on to the furnace
in the manner described.
Figs. 9, 10, 11, and 12, represent various modifications of the above
in which the chamber for heating the hot air is arranged so as to occupy
a space at the base of the chimney stack.
The arrangement shewn at Figs. 9 and 10 consists of a double
chambered chimney, and that at Figs. 11 and 12 represents the adaptation
of a chamber or annular space to be employed for heating air for the
purposes required to chimneys already crected.
In Figs. 9 and 10 A, A, are the chambers formed in the base of the
chimney by means of the partition or wall B through the centre of which
a passage is formed for enabling steam from the exhaust or other gases
to rush in in order to accelerate the draught. The entrance from such
central passage into the chimney stack is at a point above the chambers
containing the bricks, slabs, or other heat absorbing material. These

page_text: chambers communicate with the furnace and outer atmosphere in
manner as already described, with this exception, that the entrance
thoroughfares for cold air are covered with an external casing provided
with cowls or balance valves m which readily open to the pressure of
the atmosphere, and so admits cold air which freely circulates in the
space F forming the cover to the thoroughfare E, E, and which forms
entrances for such air into the chambers A, A, containing the heat
absorbing or refractory material. These chambers are alternately cut off
from the flue by the damper C actuated by the handle C¹, the action of
which simultaneously closes the lids or valves covering the air passage
not used, and opens those through which cold air has to be admitted in
accordance with the respective chambers employed for heating air.
The opening and closing of the dampers directing the heated gases
into such chambers as required are actuated by the handles n, n.
By this means the currents of heated gases from the furnace through
the chambers to the chimney, and the passage of cold air through such
heated chambers to the furnace are reversed, directed, and controlled as
desired.
In Fig. 14 an ordinary Cornish boiler is shown in longitudinal section
to which a further novelty is added for utilizing waste heat. In this
arrangement there is placed within the interior tube or flue of the boiler
a perforated tube G, one end of which rests on a seating behind the
bridge and the other extends to and terminates in the form of a thorough-
fare H, constructed in the outer walls communicating with the hot air
passage. The tube G with its perforations is so arranged that the air
passing into such tube from the outer atmosphere will be thrown
or forced out of the same in a highly heated state at an angle
with such tube, and in the direction of the current, thereby not
only materially assisting the draught, but at the same time forcing
and causing the unconsumed heated gases passing along to the flue to
impinge against the sides of the boiler tube, thereby increasing the
generative powers of such boiler; valves or dampers being supplied
that will check or increase the entrance of air into the internal per-
forated tube G.
Fig. 13 represents in vertical section the application of the improve-
ments to marine boilers, in which the vertical column p, p, of the boiler

page_text: pipes forming an annular space q, q, opening out above the deck through
slots or apertures into an annular chamber provided with a cowl 8.
This chamber supplied with the cowl, takes its bearing through the
medium of bowls or wheels upon an angle iron rail secured to the circular
vertical column p, thus enabling it by the action of the wind to be
presented in the best position for catching and conveying the cold air to
the furnace. The pipes or spaces q, q, receiving the cold air absorb heat
from the heated gases passing up the central portion t of the chimney
column, and so raises to a high temperature the downward current of
the air passing through them, which in its heated state is conveyed along
pipes to the furnace where it becomes the only agent for supplying the
fuel with the gases of combustion.
On Sheet 3 applications of the Invention are shown as adapted to
puddling furnaces and domestic kitcheners.
Figs. 15 and 16 represent in end elevation (which is shewn in part 1
section) and longitudinal section a puddling furnace. In these Figures
u is the furnace in the upper walls or crown, of which and the bridge
thoroughfares or passages v, v, v, are formed, which are the terminations
of the exterior passage w. This passage is supplied with dampers and
forms a communication with heating chambers or other equivalent 2
absorbers of heat through which air passing becomes raised to a high
temperature. In this state it rushes along the communicating passage w
to the perforated terminations v, v, v, of such passage formed in
the crown and bridge of the same, from which it issues in heated
jets, sprays, or currents, and so comes into contact with the gases
evolved from the solid fuel of the furnace, thereby effecting thorough
combustion.
2
In some cases the heated air rushing along the flue or passage w
to the furnace as described, can be partially diverted by the damper x
so as to cause one portion of such heated current to pass through 3
the opening y into the furnace below the fire bars, and the other
portion to pass through the crown and bridge in the manner as before-
described.
A swivel damper or throttle valve z placed in the hot air passage 10
enables the flow of the heated air supplying the furnaces to be reculated

page_text: In Fig. 17 the improvements are shewn as applied to an ordinary
closed kitchener. In this arrangement I perforate the chimney plate
or damper which covers the space y¹ or provide it with holes, through
which air or waste heat thrown off by the kitchener proper is conducted
into a space x¹ surrounding the flue w', which in this case is placed on
one side. The heated air in its course is conveyed along the outer
heated surface of the flue to the chamber v¹, from whence it passes into
the furnace in a highly heated state.
A great advantage derived from the employment of the above-
described arrangement beyond that of the great heat and economy of
fuel is that unpleasant smells, steam and impure but consumable gases
would be received in the space ¹, whence they would pass with the
heated air into the fire and up the side flue into the chimney instead of
escaping into the apartment.
The same or an analogous arrangement to the foregoing is applicable
to stoves or heating apparatus generally, but more particularly when
the flues are conducted under ground.
I would remark that in heating and warming apparatus I prefer the
application of the arrangement of parts shewn and described herein
relating to Figs. 6, 7, 8, 9, and 10, but on a much smaller scale as the
air passing through the heat absorbing chambers does not come into
contact with or require metal fittings.
Figs. 18, 20, and 21 represent various arrangements and applications
to flues of chimney stacks or otherwise of a mechanical means of
accelerating the draught or upward current.
In Fig. 18 the fans u', u', employed for this purpose are driven by
steam power, and are so arranged in the internal portion of the flue
that if applied, as shewn in Fig. 18 in connection with the improved
chambered stack, they will accelerate the passage of air into and through
the heat absorbing chambers to the furnace and the draught from the
furnace up the chimney stack.
Figs. 20 and 21 represent an arrangement of draught accelerators
applied to the top or summit of chimneys in which the passing wind is
caused to do service as the moter for driving the internal screw through
the medium of the wings or swiffs t, t. By the application of

page_text: these draught accelerators to chimneys, whether driven positively
by steam power or by wind a superior draught is obtained, and the
chimney does not require that altitude for the column of rarified air
to produce the draught, the height of which according to the present
arrangement is imperative. Or as a modification or addition to the
foregoing I fix outside the chimney stack near to the top thereof one
or more cowls, which receiving the wind pass it through tubes inter-
nally placed in the chimney in a position that will cause the wind so
received to rush upward, the current or force of which will either
materially aid as an auxilliary the foregoing arrangement, or be used
with advantage alone.
Having now described the nature of my said Invention, together with
the means of carrying the same into practical effect, I wish it to be
distinctly understood in conclusion that I do not wish to confine myself
to the precise details herein described, so long as the essential features
of the Invention are retained, therefore what I claim as the peculiar
feature and object of this Invention is the economizing of fuel by the
novel employment and adaptation to boilers or generators of flue
chambers or passages supplied with absorbers of heat and dampers
whereby the passage of air to the furnace of such boilers supplying the
same with the gases of combustion will be brought intimately into
contact with the waste heat escaping to the flues or chimney, in the
manner and for the purpose as herein-before described and illustrated in
the Drawings annexed.
Secondly. Conveying the heated air to the furnace from the flues,
chambers, or receptacles by means of tubes or flues and inject the
same through orifices or perforations so disposed about the furnace that
the heated gases will effectually mix with the gases evolved from the
fuel, thereby effecting their thorough combustion.
Thirdly. Placing draught accelerators in or on chimney stacks in
order to assist the influx of hot air to the furnace and eflux of waste
gases therefrom, in the manner as herein-before described and illustrated
in the Drawings annexed.
Finally. The application and employment of any one of the foregoing
arrangements adapted individually or collectively to furnaces and flues
adjacent thereto, whether employed for generating steam, puddling,

page_text: heating, or melting metals, warming, heating, or drying to be used in
the manner and for the purposes herein-before described, set forth, and
fully illustrated in the Drawings annexed.
In witness whereof, I, the said Philip Henry Williams, have here-
unto set my hand and seal, this Fourteenth day of November,
in the year of our Lord One thousand eight hundred and seventy-
three.
0
Witness,
ALEX. PRINCE,
Office for Patents,
4, Trafalgar Square,
Charing Cross,
London.
P. H. WILLIAMS. (L.S.)