IMPROVEMENTS IN OBTAINING MOTIVE POWER PROM FUEL, AIR, AND WATER
Year: 1855

page_text: LETTERS PATENT to Frederic Howorth Edwards, of Newcastle-upon-
Tyne, in the County of Northumberland, Civil Engineer, for the Inven-
tion of "IMPROVEMENTS IN OBTAINING MOTIVE POWER PROM FUEL, AIR, AND
WATER."
Sealed the 12th January 1856, and dated the 12th July 1855.
PROVISIONAL SPECIFICATION left by the said Frederic Howorth Edwards
at the Office of the Commissioners of Patents, with his Petition, on the
12th July 1855.
I, FREDERIC HOWORTH EDWARDS, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN OBTAINING MOTIVE POWER FROM FUEL, AIR, AND
WATER," to be as follows:-
I construct a close furnace or fire box in which the fuel is burnt in com-
pressed air. The gases or products of combustion pass through a valve at the
top of the fire box into an outer casing or boiler containing water. The valve
or a cap above it is arranged so as to direct the gases downwards into the water,
by which means any particles of dust which may accompany the hot gases are
retained by the water, and, subsiding to the bottom of the vessel, are blown off*
from time to time at a cock or valve. The gases ascend through the water
until they reach a diaphragm, formed of one or more layers of wire gauze or
perforated plates, or other arrangement suitable for dividing and distributing
the gases in numerous small streams. The gases thus impart their heat to the
water and convert it into steam, and the mixture of steam and air and gases

page_text: thus produced is employed for working an engine similar to an ordinary steam
engine. This engine gives motion to an air pump, which forces the air into
the close furnace to supply the combustion. In this manner the whole of the
heat produced by the combustion of the fuel is conveyed into the boiler, from
which it issues in the state of steam and heated gases, and is employed for
working the engine. The large quantity of heat which passes up the chimnies
of ordinary steam boilers is thus saved and rendered useful. In order still
farther to economize the heat, I convey the gases and steam which leave the
engine through a series of tubes, passing through a vessel which is traversed
in a contrary direction by the air which is driven in by the air pump. The
furnace is thus supplied with heated air. The air is finally driven into the
feed water through a diaphragm of wire gauze or other material presenting
numerous perforations or interstices. The feed water which supplies the boiler
is thus warmed, and very little heat escapes with the air. A portion of the
air is conveyed under the fire bars, and another portion is introduced in
several small streams above the fuel, so as to mix with the products of com-
bustion, and consume the smoke and gases. In lieu of dispersing the hot
gases through the water, the water may be dispersed amongst the hot gases by
admitting it in thin films or jets into a chamber which receives the hot gases
from the furnace. The water is thus instantaneously converted into steam,
which passes away with the gases to the engine. The fuel is supplied to
the furnace by means of a screw, and the ashes are withdrawn in a similar
The supply of fuel may be regulated by hand, or it may be effected
by driving the screw by the engine itself. The grate may be made moveable,
and supported by a lever and counterbalance. When the fuel has accumu-
lated on the grate to such an extent as to overcome the counterbalance, the
grate descends a little, and by its motion throws the screw out of gear, or
otherwise checks the supply of fuel. As the fuel burns away, the grate rises
again, and the supply of fuel again proceeds. Sight holes for examining the
fire may be fixed in the sides of the furnace.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Frederic Howorth Edwards in the Great Seal Patent Office
on the 12th January 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FREDERIC
HOWORTH EDWARDS, of Newcastle-upon-Tyne, in the County of Northumber-
land, Civil Engineer, send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twelfth day of July, in the year of our Lord One
thousand eight hundred and fifty-five, in the nineteenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the
said Frederic Howorth Edwards, Her special licence that I, the said Frederic
Howorth Edwards, my executors, administrators, and assigns, or such others
as I, the said Frederic Howorth Edwards, 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
night 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 OBTAINING MOTIVE POWER FROM FUEL, AIR, AND WATER,"
upon the condition (amongst others) that I, the said Frederic Howorth
Edwards, 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 Frederic Howorth Edwards, do hereby
declare the nature of the said Invention, and in what manner the same is
to be perforined, to be particularly described and ascertained in and by the
following statement thereof, reference being had to the accompanying Drawing,
and to the figures and letters marked thereon, that is to say :--
The Invention relates to improvements in obtaining of motive power, by
buruing fuel in compressed air, and forcing the products of combustion through
water, and applying the steam thus formed together with the products of
combustion to the actuating of a steam engine or similar engine.
Various unsuccessful attempts have been made to apply heated air and the
products of combustion to the working of engines. One cause of failure has
been the destruction of the lubricating material in the working cylinder by
the high temperature of the hot air. It has also been attempted to conduct
the products of combustion into the water of a boiler through pipes dipping
into the water, which pipes are liable to be obstructed and choked with the
dust from the fuel. To avoid this defect, the products of combustion have also
been conducted through a valve a little way below the surface of the water,
but they then pass through without properly imparting their heat to the
water. By my Invention I avoid these defects, as the hot air and gases have
a large and free passage into the boiler, and are afterwards minutely subdivided

page_text: by a wire gauze diaphragm, or otherwise, so as to bring them intimately
in contact with the water, and thus produce a large quantity of steam,
and at the same time to reduce the temperature of the air and gases so
as to prevent their acting injuriously upon the working parts of the engine, or
on the materials employed for lubricating the same.
Figure 1 of the accompanying Drawing is a front view, and Figure 2 is a
back view, of a boiler or generator constructed according to my Invention;
Figure 3 is a section; and Figure 4 is a plan of the same. Figure 5 is a
horizontal section of the upper part of the apparatus, showing the arrangement
of the wire gauze diaphragm, herein-after mentioned; Figure 6 is a plan of
the base or lower part of the apparatus.
The same letters refer to similar
parts in all the Figures.
A is a close furnace or fire box, inclosed in the outer casing or boiler B; C
is the grate or fire bars; D is the ash-pit, which has a close fitting door E;
F is the fire door. These doors are fitted air-tight, or are made so by a little
lute, and they are secured by cross bars and screws e, f. G is a pipe which con-
ducts a supply of compressed air from an air pump or blowing cylinder to the
valve a, whence it passes partly into the pipe d leading to the ash-pit, and partly
through the pipe 6 into the pipe or hollow belt c, whence it passes through a
series of short tubes into the fire box A. Figure 7 is a section, shewing the
arrangement of the valve a. By raising this valve the air is entirely directed
to the ash-pit under the fire bars. By depressing the valve the air is entirely
directed through the pipes b and c to the fire box above the fire bars. By
placing the valve in an intermediate position, the air may be directed partially
above and partially below the fire bars, and the combustion can thus be regu-
lated. His a pipe in the form of a cross, with four outlets or branches. The
lower branch communicates with the fire box A. The upper branch carries a
valve I, opening upwards into the boiler, and covered by a cap or dome J.
One of the horizontal branches communicates with the chimney K through
an air-tight valve or register L, which may be opened and closed by the
handle ; or this branch may be closed by a door or lid, similar to the doors
E and F. The other horizontal branch communicates with an air-tight
coal box or reservoir M, containing an archimedean screw N, by turning
which the coal is propelled-forward-and-falls-into-the-fire-box. The
spindle of the screw passes through a stuffing box n, and carries a ratchet
wheel O, which is worked by a paul on the lever P. m is an air-tight lid or
door, through which coal or coke or other fuel is introduced into the box M.
The grate C is supported by a lever or arm Q on the spindle g, which passes
through a stuffing box r, and carries a long arm or lever R, which carries a

page_text: The
balance weight, and is connected by a rod s and link t to a forked rod S,
which is driven backwards and forwards by the engine by means of an
eccentric or otherwise. The forked rod S drives a
pin on the lever P. The
fuel is thus constantly and gradually supplied by the screw N, until it accumu-
lates on the grate C, and overcomes the balance weight on the lever R; the
grate then descends a little, and lifts the forked rod S off the pin on the lever
P; the rod S then moves backwards and forwards without moving the
lever P, and the supply of fuel is arrested until a sufficient portion of the fuel
on the grate C has been consumed to allow of the grate rising again. In the
upper part of the generator is fixed a diaphragm T, of wire gauze or per-
forated metal, which is placed between and supported by two gratings U, V.
In Figure 5 a portion of the wire gauze T and of the upper grating V are
removed, so as to show the lower grating U. W is the steam pipe which
conveys the steam and products of combustion to the engine; wis a safety
valve; X is a small cylinder, containing a piston x, which is connected by a
lever y and rod z to the air valve a; Y is the feed pipe, for supplying the
boiler or generator with water from a feed pump worked by the engine. The
generator is set in action in the following manner:-The outer casing B is
filled with water to a height of a few inches above the diaphragm T.
doors E and F and the valve L are opened, and the fire is lighted on the
grate C in the ordinary manner. The door m is also opened, and the box M
is filled with coal, coke, anthracite, or other fuel, and the door m is again
closed air-tight. When steam of sufficient pressure is thus raised in the
generator, the doors E and F and the valve L are closed, and the steam is
turned on to the engine, which is thus started. The air pump worked by the
engine immediately begins to force air through the pipe d under the fire bars,
thus supporting and increasing the combustion. The pressure of the air in
the fire box increases until it exceeds that of the steam in the boiler; it then
lifts the valve I, and enters the boiler or outer casing, and is directed down-
wards by the cap or dome J. The hot air and products of combustion com-
municate their heat to a certain extent to the water and convert it into steam.
This effect is, however, only partial, as the streams of hot air and gases ascend
very rapidly and in large masses until they arrive at the wire gauze or perforated
diaphragm T, which divides them into a multitude of fine streams or bubbles,
and brings them into intimate contact with the water. The diaphragm is
not placed immediately over and close to the valve I, as it would then be
liable to become choked with any particles of dust carried up with the hot
gases. These particles of dust are brought in contact with the water, and
wetted by means of the cap J, and they settle to the bottom of the boiler,

page_text: and are blown off at sludge cocks from time to time. The steam and
products of combustion pass off by the steam pipe W to the engine. If the
pressure in the boiler increases beyond the required amount, it raises the
piston x, and shuts off a portion or the whole of the air from below the fire
bars, and admits a greater portion above the fire bars. The combustion is
thus checked. If, on the contrary, the pressure falls, the piston a descends,
and admits more air below and less above the fire bars, and thus increases the
combustion.
The steam and products of combustion on leaving the engine are conducted
through a refrigerator, consisting of a series of tubes, passing through a vessel
which is traversed in a contrary direction by the fresh air in its passage from
the air pump to the generator. From the refrigerator the waste steam and
products of combustion are conducted under a diaphragm of wire gauze or
perforated metal in a vessel which contains the feed water for the supply of the
boiler. The steam or a portion of it is thus condensed, and the gases are
partially cooled, and a supply of hot water is obtained for feeding the boiler
The refrigerator or the apparatus for warming the feed water, or both, may,
however, be dispensed with, although with some diminution of the economy
of fuel.
The apparatus admits of variation in the details, provided the peculiar
character of the Invention be retained. Thus, in lieu of the wire gauze or
perforated plate, a grating covered with iron balls or shot or other suitable
materials may be employed to subdivide and distribute the hot air and gases.
Two or more such apparatus, or two or more diaphragms of wire gauze or
perforated metal, may be employed, and placed one above the other, so as
repeatedly to break up the streams of air and gases and distribute them in
the water.
Having now described the nature of the Invention, and in what manner
the same is to be performed, I wish it to be understood that I do not confine
myself to the precise details herein-before described, as the same may be
varied, nor do I claim generally the effecting the combustion of fuel in a close
furnace supplied with compressed air and conducting the resulting hot air and
products of combustion into water in a boiler; but what I claim is,―
Firstly, the effecting the combustion of fuel in a close furnace supplied with
compressed air, and then conducting and distributing the resulting hot air and
products of combustion in the water in a boiler by means of a valve, and a
diaphragm of wire gauze or perforated metal, or similar means of distribution,
immersed in the water, as herein-before described.
Secondly, the method of supplying fuel to a close furnace from a close box

page_text: or reservoir by means of an archimedean screw, regulated by the rising and
falling of the grate, as herein-before described.
Thirdly, the mode of heating the feed water, by distributing the waste steam
and gases in it by means of a wire gauze or perforated diaphragm or distributor
as herein-before described.
Fourthly, the application to a close furnace or fire box communicating by a
valve with an outer casing or boiler, of a wire gauze or perforated diaphragm
or distributor, as herein-before described.
Fifthly, the constructing a generator with a close furnace or fire box, having
a moveable grate, and communicating by a valve with an outer casing or boiler
provided with a wire gauze or perforated diaphragm or distributor, and having
a close box or reservoir for fuel, with an archimedean screw, regulated by the
rising and falling of the moveable grate, as herein-before described.
In witness whereof, I, the said Frederic Howorth Edwards, have here-
unto set my hand and seal, this Eighth day of January, in the year of
our Lord One thousand eight hundred and fifty-six.
FREDERIC HOWORTII EDWARDS. (L.S.)