IMPROVEMENTS IN GENERATING HEAT, AND IN APPLYING IT FOR THE PRODUCTION OF MOTIVE POWER AND STEAM, ALSO IN ADDARATING EMPLOYED THEREIN
Year: 1866

page_text: LETTERS PATENT to Matthew Piers Watt Boulton, of Tew Park, Oxford-
shire, Esquire, for the Invention of "IMPROVEMENTS IN GENERATING HEAT,
AND IN APPLYING IT FOR THE PRODUCTION OF MOTIVE POWER AND STEAM, ALSO
IN ADDARATING EMPLOYED THEREIN "
Sealed the 7th September 1866, and dated the 10th March 1866.
PROVISIONAL SPECIFICATION left by the said Matthew Piers Watt
Boulton at the Office of the Commissioners of Patents, with his
Petition, on the 10th March 1866.
I, MATTHEW PIERS WATT BOULTON, of Tew Park, Oxfordshire, Esquire,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
GENERATING HEAT, AND IN APPLYING IT FOR THE PRODUCTION OF MOTIVE POWER
AND STEAM, ALSO IN APPARATUS EMPLOYED THEREIN," to be as follows:-
This Invention relates to improvements in the application of heat to the
production of motive power, having for its principal object to enable a larger
portion of heat to be converted into mechanical effect than is done in the best
engines now used.
In the working of ordinary steam engines the expansion of the air and
gases in the furnaces affords a source of mechanical power which is not used.
With a view to obtaining the maximum effect from the heat it is desirable
that the expansive force produced by the combustion of the fuel should be
used to produce mechanical effect, and that the heat remaining in the pro-
ducts of combustion after they have performed work should be further utilized

page_text: as a source of motive power. For this purpose it may be employed to gene-
rate steam in a boiler or vessel, the steam so generated being used to perform
work in an engine.
For this purpose the following method may be employed :-An inflammable
mixture, such as a mixture of air with inflammable gas or vapour, is ignited
in a cylinder, the expansive force thus produced giving motion to a piston,
and thus performing work as in an ordinary gas engine. The products of
combustion after their discharge from the cylinder are employed to heat water
in a boiler and to generate steam, the steam thus generated being used to
produce motive power. The expansive force produced by the ignition of the
inflammable mixture and that produced by the steam may both be employed
to work the same engine; they may be used in the same cylinder or in
different cylinders; their power may be combined in various ways. The
water employed to keep the cylinder and other parts of the gas engine cool
may be contained within a close vessel, the steam generated from it being
employed in conjunction with the steam otherwise generated to perform work
in an engine. The heat abstracted from the cylinder, or a portion of it, may
also be employed to heat the feed water of the boiler, or to heat the material
from which the inflammable gas or vapour is generated. The inflammable
mixture may be introduced into the cylinder in which it is used at the atmo-
spheric pressure, or it may be introduced into the cylinder at a pressure
exceeding that of the atmosphere to any degree desired.
In the gas engine as ordinarily constructed a portion of the stroke, viz.,
while the charge of air and gas is. being drawn into the cylinder, is performed
only in virtue of the momentum previously acquired. To obviate this the
following construction may be used:-Two cylinders are employed in which
pistons work. The office of one of these cylinders is to receive the successive
charges of the inflammable mixture, while in the other the expansive force
produced by the ignition acting on the piston drives the engine. The area
of the piston in this latter cylinder is larger than the area of the piston in the
former. After the charge is ignited communication is opened between these
two cylinders, and the pressure of the fluid acting on the larger piston pre-
vails, causing the smaller piston to move against pressure, and to drive the
products of combustion into the larger cylinder. While this is being done
products of combustion which have been cooled by generating steam, but
whose temperaturo is higher than that of the water in the boiler which cools
the exterior of the charging cylinder, may be admitted into that cylinder. On
the next stroke communication is closed between the two cylinders, and a
fresh charge of inflammable mixture is introduced into the charging cylinder.

page_text: At the moment of ignition the piston in the charging cylinder may be
detached from the machinery, so that no shock can be caused to the engine
by explosion. The fluid may be introduced into the charging cylinder at
high pressure. A piston working in a larger cylinder may drive it in com-
pressing it. By employing two charging cylinders the arrangement may be
made double acting. After the products of combustion have performed work
in the larger cylinder they are employed to heat water by acting on the
exterior of a boiler, and to generate steam as previously described.
The following method may also be employed :-The products of combustion,
instead of passing direct from the charging cylinder into the larger cylinder,
pass in the first place into the interior of a boiler or vessel, in which they heat
water and generate steam. From this vessel the gases and steam pass together
to the larger or working cylinder, and there act on the piston. In this case after.
the piston in the charging cylinder has made its stroke fluid from the boiler.
or the vessel in which steam is generated may be admitted into the charging
cylinder. On the next stroke this fluid may be driven back into the boiler
against pressure by the piston, while the fresh charge of inflammable mixture
is introduced into the charging cylinder; or otherwise this fluid may expand,
performing work in the working cylinder while the piston in the charging
cylinder pauses. Communication between that cylinder and the boiler is in
the meantime cut off.
Instead of employing two detached cylinders the following construction
may be used:-The two cylinders have the same axis, and the pistons or
plungers working in them are connected. After the ignition of the inflam-
mable mixture in the smaller or charging cylinder communication is opened
between that cylinder and the other cylinder in which a larger area of surface
is exposed to the pressure of the fluid, which acts on this area in an opposite
direction. The pressure on the larger area prevailing the piston or plunger
in the charging cylinder is forced backwards, so that it drives the products of
combustion out of the charging cylinder into the other cylinder. By employing
two charging cylinders the arrangement may be made double acting.
Various modes of construction may be adopted for performing this opera-
tion. Thus a central plunger may be united to two pistons, or two plungers.
may be united to a piston working in a larger central cylinder, or two pistons
may be connected with a piston working in a larger central cylinder. Other-
wise a plunger working in a smaller cylinder may be united to a piston working
in a larger cylinder, on the other side of which piston is a trunk or cylindrical
body connected with the engine whose diameter is larger than that of the
plunger. After ignition communication is opened between the charging

page_text: cylinder and the annular space around the trunk. The area on which the fluid
there acts is larger than the area of the plunger in the charging cylinder upon
which it acts in the opposite direction, and accordingly the pressure of the
fluid forces the plunger back, causing the products of combustion to enter the
annular space in the working cylinder. When the stroke is completed com-
munication is opened between this annular space and that on the other side
of the piston, where a larger area is presented to the action of the fluid.
Accordingly they expand in this space, causing the piston to return, while a
fresh charge is admitted into the charging cylinder. When the products of
combustion are used within the interior of the vessel in which steam is
generated the following method may be adopted :-A charge of air and a
charge of inflammable fluid are driven or forced from separate vessels into
a tube or chamber within the boiler or communicating with the boiler, within
which tube or chamber the fluids are intimately mixed, and as they are
mixing undergo combustion. The products of this combustion pass onwards
through the boiler or vessel in which steam is generated and generate steam.
In the meantime communication is open between the boiler or evaporating
chamber and the working piston, so that the products of combustion are
taken off as fast as they are generated, and are not forced back by increase of
pressure into the vessels from which they issue.
Instead of inflammable gas or vapour liquid, such as petroleum or hydro-
carbons, may be used. A portion of this is injected into a chamber, and a
portion of air caused to act upon it, so that combustion is produced. For
this purpose the liquid may be forced to pass through a porous material, or
through the interstices of wires, or through a tube or passage pierced with
numerous holes. It may be forced through these in a heated state so as to
render it more easily combustible. A portion of the charge of air is caused
to pass immediately in contact with the liquid which is ignited, and mixing
with the portion of air thus supplied to it undergoes partial combustion,.
whilst the rest of the air driven into a passage in which it mixes with the flame
and vapour completes the combustion. A similar method may be employed
when it is desired to employ petroleum or bydrocarbons as fuel for any pur-
pose.
The liquid is caused to pass through pores, apertures, or passages ;
previous to being forced through these it may be heated. A certain quantity:
of air is caused to pass through a space adjoining the apertures through which
the liquid issues, and partial combustion take place in this space. This heats
the apertures through which the liquid issues. The vapour or aeriform
matter which has not undergone combustion passes on into a chamber or
passage in which a further quantity of air is caused to mix with it, and here

page_text: the combustion is completed. The combustion thus caused may be used for
any purpose desired, as for heating the boiler of a steam engine.
When products of combustion have been introduced into the interior of a
boiler or vessel the mode in which they are caused to act on the water within
the boiler or vessel and to generate steam may be varied in many different
ways. They may be caused to rise in streams or bubbles through the water,
and in this case their path through the water may be lengthened by the
interposition of plates or bodies. They may be caused to pass through a
chamber within which a jet of water plays, or numerous jets of water play,
causing the water to be dashed about in particles of fine spray, which are sur-
rounded by the heated gases and converted into steam; or the water may be-
introduced into the chamber in numerous streams through fine apertures, and
I may also be made to flow over plates or bodies or through apertures in them.
Again, the products of combustion may be caused to pass through passages,
the sides of which are wetted by water flowing over them, or by water per-
colating through pores or apertures in them, or in other ways; they may be
caused to pass through passages over the other sides of which water flows.
When it is desired to spread a thin film of water over surfaces on which
the heated gases may act and generate steam the following method may be
used-Plates are employed which are capable of being moved so that they
can be brought together or separated; this movement can be imparted to
them by means of a rod worked by the engine. When they are separated a
certain quantity of water is injected between them; when they are brought
together this water is forced to spread itself over them in a thin film. The
surfaces of the plates being thus wetted the hot gases are caused to pass.
through the spaces between them, converting the film of water upon them
into steam. Again, the heated gases may be caused to pass through passages
the other sides of which are sides of a vessel containing water; thus they may
be caused to pass through tubes surrounded by water, or through flat-sided
passages, or through cylindrical passages, or passages of other forms, on the
other side of which is water. As the products of combustion and the water
to which they impart heat are both at equal pressure, both being within the
boiler, the sides of the passages may be very thin.
The above-described methods may also be combined in various ways. A
pump or forcing apparatus may be employed to cause the water to circulate
through the passages. A regulating apparatus may be employed so that
when the pressure in the boiler exceeds a certain point the supply of inflam-
mable fluid to the cylinder or vessel in which it is burnt is diminished, and

page_text: gases
After the engine has worked
has acquired heat, and the
thus less heat is produced and less steam generated, while if the pressure falls
below a certain point the reverse action takes place. When combustion is
caused to take place within the boiler or evaporating vessel by the action of
the engine the first stroke of the engine cannot be caused in the same way
as the strokes when the engine is in regular action. For starting the
engine in the first instance heat may be applied externally to the boiler, or an
explosive compound or compounds which rapidly liberates gas may be intro-
duced into the working cylinder or into a vessel connected with this, the
generated from which cause the piston to move.
and the water in the boiler or evaporating vessel
fluid in that vessel has acquired pressure, then so long as this heat and
pressure, or a sufficient portion of them, are retained there is a stock of elastic
forco ready to start the engine at any moment. If the surface of the boiler
or vessel is principally covered with materials which are bad conductors of
heat, then a very small application of heat from the exterior will suffice to
keep up the heat and pressure within the vessel, and thus retain the stock of
clastic force. Similarly, if inflaminable vapour, such as vapour of petroleum
or of hydrocarbons, is used as an ingredient of the inflammable mixture, when
the requisito heat and pressure has been attained in the vessel in which this
vapour has been generated it may be maintained by the application of a small
external beat. When the air employed is used at a high pressure a series
of pumps for the compression of the air may be employed, the first compressing
it to a certain degree of pressure, the next to a higher degree of pressure, and
so on. Water may be used for filling the cylinders of the pumps at the end
of the strokes, and the various constructions and materials which have been
used for valves in pumps used for compressing air may be employed. The
steam generated may be employed to perform work by acting as a blast or in
numerous jets or blasts forcing air along with itself into a vessel, the mixed
air and steam thus forced into the vessel being employed to move a piston in
a cylinder or perform work in an engine. When it is employed in this way
the air and steam after their entrance into the vessel may be heated by being
caused to pass through numerous tubes or passages, or in other ways, and by
this beat any steam which has been condensed may be reconverted into steam
and if desired may be superheated. Instead of forcing air into a vessel the
blast or blasts of steam may force steam into a vessel, the steam thus forced
into the vessel being employed to perform work in an engine. Steam which
has been discharged from this engine after performing work may be agai
driven by the blast of issuing steam into the vessel, and again perform work

page_text: in the engine. The steam after its entrance into the vessel may be subjected
to heat, as previously described;. steam acting as above described. may be
generated by heat applied in any manner described..
When the products of combustion are employed to act externally on a
boiler the following construction may be employed:-Tubes aro set within a
cylindrical vessel of the form of a locomotive boiler; between the cylindrical
shell and the tubes is a curved partition. The space between the shell and
the partition becomes gradually narrower towards the bottom and. wider
towards the top; just at the top the divergence is more rapid, so that here a
rapidly expanding mouth or channel is formed.. This partition is pierced with
holes or apertures, so that water which has descended between the partition
and the outer cylindrical shell can pass through these apertures and rise
upwards through the interior part of the boiler in which the tubes are placed.
The water in the space between the partition and the envelope of the boiler
not being beated by the tubes is constantly cooler and heavier than the fluid
among the tubes where the steam is generated, and thus a regular circulation
is established, the water constantly descending through. the channel between
the partition and the outer envelope, and constantly passing through the
apertures in the partition and rising among the tubes. The widening of the
channel in the upper part allows the downward current of water to be formed
without interference froin the ascending current. The circulation thus
established may be augmented by means of a pump. or forcing apparatus,
which constantly draws water from the upper part of the water in the boiler
and forces it into the space between the shell of the boilor and the partition.
in which it is desired to maintain a descending current. When the form of
the envelope of the boiler is other than cylindrical a similar method may be
employed.
The following is another form of boiler which may be used:-Tubes are
inserted in a vessel, which may be cylindrical or may be of other forms;
within these tubes are other tubes having openings at the bottom so that
water can pass down the interior tubes and ascend in the space between tho
interior and exterior tubes; these interior tubes enter a vessel.. A pump or
forcing apparatus constantly draws the water from that part of the boiler
which it enters after ascending through the spaces between the tubes and
forces it into the vessel in which the interior tubes. are inserted, thus causing
constant circulation; the tubes aro exposed to beat as in other cases.. It is
desirable that the gases which impart beat to them should be caused to move
in a direction opposite to that in which the water moves in the spaces between
the external and internal tubes.

page_text: In such a case
Boilers constructed as above described may be employed for general pur-
poses. Whatever be the form of the boiler used a pump or forcing apparatus
may always be employed to cause a circulation of the water.
some portion of the power of the engine is expended in working the pump, but on
the other hand the heating surface is rendered more efficient, and the boiler can
be made smaller and lighter. When the expansive force of heated products
of combustion is used to perform work on a piston in a cylinder the water or
cooling agency employed to keep the cylinder cool abstracts heat from the
gases while they are performing work, and thus diminishes their expansive
force, causing loss of power. In order to obviate this it is desirable that the
action of the gases while performing work should be very rapid, so that the
cooling agency of the water or other material employed to cool the cylinder
may have little time to abstract heat from the gases while they are performing
work. With the view of effecting this the expansive force of the gases may
be employed to compress air or aeriform fluid in a receiver from which its
return is prevented by valves; the air or fluid thus compressed is used to
produce motive power. The products of combustion having performed work
in driving the air into the receiver are afterwards employed to heat water and
generate steam; the steam so generated is employed to perform work in an
engine either conjointly with the compressed air or separately, as desired.
The charge of inflammable mixture may act in cylinder into which it is
introduced; it may be introduced through numerous passages; it may be in
immediato contact with the air or fluid in front of it which it is desired to drive
into the receiver, or it may be separated from this by a piston, which piston
is propelled by the expansive force of the ignited mixture, and drives the air
or fluid into the receiver. Again, a moveable partition may be employed
which for a while separates the inflammable mixture from the non-inflam-
mable fluid, this partition being removed just previous to the ignition of the
mixture. After the propulsive force of the ignited mixture is spent and the
air or fluid driven into the receiver, a piston is caused to make a stroke in
the cylinder, expelling the heated products of combustion through an eduction
valve, whence they pass to a passage or passages, in traversing which they
heat water and generate steam in a boiler or vessel. On the return stroke of
the piston a fresh charge of the inflammable mixture and of the air or fluid to
be compressed by it is introduced into the cylinder. The charge of inflam-
mable mixture and the air or non-inflammable fluid which it compresses and
drives into the receiver may be introduced into the cylinder at the atmospheric
pressure, or they may be introduced into it at a high pressure exceeding that
of the atmosphere to any extent desired. When a high pressure is used a

page_text: larger portion of heat can be converted into work by the expansion of the
ignited inflammable mixture. The piston which is employed to move through
the cylinder in order to expel the products of combustion may be worked
mechanically by the engine, or it may be worked by means of the compressed
air or fluid which has been forced into the receiver by the expansive force of
the ignited mixture; the steam generated as previously described may be
mixed with this compressed air or fluid. The fluid thus acting on the piston
may expand to the pressure at which it is desired to use the charge, and on
the return of the piston a portion of it may enter the cylinder on the other
side, thus introducing fluid into the cylinder to be driven into the receiver by
the ignited gases at the desired pressure. The remaining portion may bo
compressed by the movement of the piston, this compressed fluid re-expanding
and performing work in the succeeding stroke. The piston while pressed by
the fluid may perform work on the engine, or it may compress air which per-
forms work on the engine. Again, fluid which has performed work in another
cylinder and has expanded to the desired pressure may be introduced into
the cylinder for the purpose of being driven into the receiver by the ignited
charge of inflammable mixture. If the piston is worked mechanically by the
engine products of combustion which have been cooled by heating water and
generating steam, but whose temperature is still higher than that of the water
in the boiler, may be employed to enter the cylinder behind the piston, and so
to prevent internal cooling of the cylinder at that stage of the operation..
When the piston has reached the confines of that part of the cylinder which
it is desired to fill with the inflammable mixture a partition may be interposed.
between the part of the cylinder into which the charge is introduced and the
other part, so as to prevent intermixture of the fluids in the two portions of
the cylinder while the charge is being introduced; this partition is removed
just previous to the ignition of the inflammable mixture. This partition may
be formed of a plane or planes which slide in a direction transverse to the
axis of the cylinder, or a revolving plane may be used pierced by an eccentric
aperture, or a revolving spherical piece may be employed pierced with a cylin-
drical passage. By the revolution of this piece the axis of this cylindrical
passage is sometimes made to coincide with the axis of the cylinder so as to
allow free passage from one side of the cylinder to the other, whilst sometimes
it is brought into a position transverse to the axis of the cylinder. Instead
of a piston working in the cylinder a plunger may be employed. Again, tho
piston which works in the cylinder may be attached to a trunk of smaller
diameter than itself; in this case the products of combustion, after they have
been discharged at one end of the cylinder, and have been cooled by heating.

page_text: water and generating steam may re-enter the cylinder of the other end,
filling the annular space around the trunk. The piston on which the fluid
at high pressure acts may be attached to the same trunk working in a separate
cylinder. When this method of construction is employed, if the pressure of
the heated products of combustion after their expansion is reduced below the
atmospheric pressure, the contraction of volume which the heated gases
undergo when they heat water and cause steam to be generated becomes
utilized as a source of power.
The various different modes of construction which have been previously
described with reference to the gas engine may be used to produce the same
effect. Valves may be employed between the cylinder in which the inflam-
mable fluid acts and the chamber or passages in which tho heated products
of combustion heat the water in the boiler or vessel, so that the pressure in
this chamber or passages may be constantly less than the atmospheric
pressure. Instead of compressing air or fluid in a vessel the expansive force
of the ignited inflammable mixture may be employed to drive air or fluid into
the atmosphere, its return into the cylinder being prevented by valves; in
this case the expansive force takes effect by producing a partial vacuum in
the cylinder, i. e., a pressure less than that of tho atmosphere. The cou-
traction which the gases undergo on cooling as they generate steam may be
utilized, as previously described. In this case the difference between tho
atmospheric pressure and the lower pressure produced within the cylinder is
used as the means of producing motive power. If it is not desired to utilizo
heat of the gases after they have performed work for the generation of
steam, then constructions similar to those previously described may be
employed, with this difference, that the water employed for the purpose of
cooling is not confined in a close vessel under pressure, and that either no
steam is generated from it, or that such steam as is generated from it is
discharged as waste.
SPECIFICATION in pursuanco of the conditions of the Letters Patent, filed 30
by the said Matthew Piers Watt Boulton in the Great Seal Patent
Office on the 10th September 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, MATTHEW
PIERS WATT BOULTON, of Tew Park, Oxfordshire, Esquire, send greeting.
WHEREAS er most Excellent Majesty Queen Victoria, by Iler Letters 35
Patent, bearing date the Tenth day of March, in the year of our Lord One
thousand cight hundred and sixty-six, in the twenty-ninth year of Her reign,

page_text: did, for IIerself, IIer heirs and successors, give and grant unto me, the said
Matthew Piers Watt Boulton, Her special licence that I, the said Matthew
Piers Watt Boulton, my executors, administrators, and assigns, or such others.
as I, the said Matthew Piers Watt Boulton, 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 Inven-
tion for "IMPROVEMENTS IN GENERATING HEAT, AND IN APPLYING IT FOR THE
PRODUCTION OF MOTIVE POWER AND STEAM, ALSO IN APPARATUS EMPLOYED THEREIN,"
upon the condition (amongst others) that I, the said Matthew Piers Watt
Boulton, 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 tho
same was to be performed, and cause the samo 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 Matthew Piers Watt Boulton, do hereby
declare the nature of the said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say:-
In the working of ordinary steam engines the expansion of the air and
gases in the furnaces affords a source of mechanical power which is not used.
With a view to obtaining the maximum effect from the heat it is desirable
that the expansive force produced by the combustion of the fuel should be
used to produce mechanical effect, and that the heat remaining in the products
of combustion after they have performed work should be further utilized as a
source of motive power. For this purpose it may be employed to generate
steam in a boiler or vessel, the steam so generated being used to perform work
in an engine.
In order to effect the object, above described the following method may be
employed: An inflammable mixture, such as a mixture of air with
inflammable gas or vapour, is ignited in a cylinder, the expansive force thus
produced giving motion to a piston and thus performing work as in an ordinary
gas engine. The products of combustion after their discharge from the
cylinder are employed to heat water in a boiler and to generate steam, the
steam thus generated being used to produce motive power. The expansive
forco produced by the ignition of the inflammablo mixture and that produced
by the steam may both be employed to work the same engine; they may be

page_text: used in the same cylinder or in different cylinders; their power may be
combined in various ways. The water employed to keep the cylinder and
other parts of the gas engine cool may be contained within a close vessel,
tho steam generated from it being employed in conjunction with the steam
otherwise generated to perform work in an engine. The heat abstracted
from the cylinder or a portion of it may also be employed to heat the feed
water of the boiler, or to beat the material from which the inflammable
gas or vapour is generated. The inflammable mixture may be introduced
into the cylinder in which it is used at the atmospheric pressure, or it may be
introduced into the cylinder at a pressure exceeding that of the atmosphere to
any degree desired.
In the gas engine as ordinarily constructed a portion of the stroke, viz.,
while the charge of air and gas is being drawn into the cylinder, is performed
only in virtue of the momentum previously acquired. To obviate this the
following construction may be used:-Two cylinders are employed in which
pistons work. The office of one of these cylinders is to receive the successivo
charges of the inflammable mixture, while in the other the expansivo force
produced by the ignition acting on the piston drives the engine. The area of
the piston in this latter cylinder is larger than the area of the piston in the
former. After the charge is ignited communication is opened between these
two cylinders, and the pressure of the fluid acting on the larger piston
prevails, causing the smaller piston to move against pressure and to drive the
products of combustion into the larger cylinder. While this is being done
products of combustion which have been cooled by generating steam, but
whose temperature is higher than that of the water in the boiler which cools
the exterior of the charging cylinder, may be admitted into that cylinder. On
the next stroke communication is closed between the two cylinders and a
fresh charge of inflammable mixture is introduced into the charging cylinder.
At the moment of ignition the piston in the charging cylinder may be
detached from the machinery so that no shock can bo caused to the engine by
explosion. The fluid may be introduced into the charging cylinder at high
pressure. A piston working in a larger cylinder may drive it in compressing
it. By employing two charging cylinders the arrangement may be made
double acting. After the products of combustion have performed work in
the larger cylinder they are employed to heat water by acting on the exterior 2
of a boiler, and to generate steam as previously described.
The following method may also be employed:-The products of combustion,
instead of passing direct from the charging cylinder into the larger cylinder,
pass in the first place into the interior of a boiler or vessel, in which they heat

page_text: water and generate steam. From this vessel the gases and steam pass
together to the larger or working cylinder and there act on the piston. In
this case while the piston in the charging cylinder is making its stroko fluid.
from the boiler or the vessel in which steam is generated may be admitted
into the charging cylinder. On the next stroke this fluid may be driven back
into the boiler against pressure by the piston, while the fresh charge of
inflammable mixture is introduced into the charging cylinder; or otherwise
this fluid may expand, performing work in the working cylinder while the
piston in the charging cylinder pauses. Communication between that cylinder
and the boiler is in the meantime cut off.
Instead of employing two detached cylinders the following construction may
be used:-The two cylinders have the same axis and the pistons or plungers
working in them are connected. After the ignition of the inflammable
mixture in the smaller or charging cylinder communication is opened between
that cylinder and the other cylinder in which a larger area of surface is
exposed to the pressure of the fluid, which acts on this area in an opposite
direction. The pressure on the larger area prevailing the piston or plunger
in the charging cylinder is forced backwards, so that it drives the products of
combustion out of the charging cylinder into the other cylinder. By
employing two charging cylinders the arrangement may be made double
acting.
Various modes of construction may be adopted for performing this operation.
Thus, a central plunger may be united to two pistons, or two plungers may
be united to a piston working in a larger central cylinder, or two pistons may
be connected with a piston working in a larger central cylinder. Otherwise
a plunger working in a smaller cylinder may be united to a piston working in
a larger cylinder, on the other side of which piston is a trunk or cylindrical'
body connected with the engine whose diameter is larger than that of the:
plunger. After ignition communication is opened between the charging
cylinder and the annular space around the trunk. The area on which the
fluid here acts is larger than the area of the plunger in the charging cylinder.
upon which it acts in the opposite direction, and accordingly the pressure of
the fluid forces the plunger back, causing the products of combustion to enter
the annular space in the working cylinder. When the stroke is completed
communication is opened between the annular space and that on the other
side of the piston where a larger area is presented to the action of the fluids.:
Accordingly they expand in this space, causing the piston to return, while a
fresh charge is admitted into the charging cylinder. When the products of
combustion are used within the interior of the vessel in which steam is gene-
:

page_text: rated the following method may be adopted :-A charge of air and a charge
of inflammable fluid are driven or forced from the separate vessels into a tube
or chamber within the boiler or communicating with the boiler, within which
tube or chamber the fluids are intimately mixed, and as they are mixing
undergo combustion. The products of this combustion pass onwards through
the boiler or vessel in which steam is generated and generate steam. In the
meantime communication is open between the boiler or evaporating chamber
and the working piston, so that the products of combustion are taken off as
fast as they are generated, and are not forced back by increase of
the vessels from which they issue.
pressure into
Instead of inflammable gas or vapour liquid, such as petroleum or hydro-
carbons, may be used. A portion of this is injected into a chamber and a
portion of air injected into the same chamber so as to come in contact with
the liquid, which is ignited and undergoes combustion. For this purpose the
liquid may be forced to pass through a porous material, or through the inter-
stices of wires, or through a tube or passage pierced with numerous holes."
It may be forced through these in a heated state so as to render it moro
easily combustible. A portion of the charge of air is caused to pass
immediately in contact with the liquid which is ignited, and mixing with the
portion of air thus supplied to it undergoes partial combustion, whilst the rest
of the air driven into a passage in which it nixes with the flame and vapour
completes the combustion. A similar method may be employed when it is
desired to employ petroleum or hydrocarbons as fuel for any purpose. The
liquid is caused to pass through pores, apertures, or passages; previous to
being forced through these it may be heated. A certain quantity of air is
caused to pass through a space adjoining the apertures through which the
liquid issues, and partial combustion takes place in this space. This beats the
apertures through which the liquid issues. The vapour or aeriform matter
which has not undergone combustion passes on into a chamber or passage in.
which a further quantity of air, which may be heated by passing through tubes
or channels on which the flame plays, is caused to mix with it, and hero the
combustion is completed. The combustion thus caused may be used for any
purpose desired, as for beating the boiler of a steam engine.
When products of combustion have been introduced into the interior of a
boiler or vessel the mode in which they are caused to act on the water within
the boiler or vessel and to generate steam may be varied in many different
ways. They may be caused to rise in streams or bubbles through the water,
and in this case their path through the water may be lengthened by the inter-
position of plates or bodies; they may be caused to pass through a chamber

page_text: within which a jet of water plays, or numerous jets of water play, causing the
water to be daslied about in particles of fine spray which are surrounded by
the heated gases and converted into steam; or the water may be introduced
into the chamber in numerous streams through fine apertures, and may also
be made to flow over plates or bodies or through apertures in them. Again,
the products of combustion may be caused to pass through passages the sides
of which are wetted by water flowing over them, or by water percolating
through pores or apertures in them, or in other ways; they may be caused
to pass through passages over the other sides of which water flows.
When it is desired to spread a thin film of water over surfaces on which
the heated gases may act and generate steam the following method may bo
used-Plates are employed which are capable of being moved so that they
can be brought together or separated. This movement can be imparted to
them by means of a rod worked by the engine. When they are separated a
certain quantity of water is injected between them; when they are brought
together this water is forced to spread itself over them in a thin film. The
surfaces of the plates being thus wetted the hot gases are caused to pass
through the spaces between them, converting the film of water upon them
into steam. Again, the heated gases may be caused to pass through passages
the other side of which are sides of a vessel containing water. Thus they may
be caused to pass through tubes surrounded by water, or through flat-sided
passages, or through cylindrical passages, or passages of other forms, on the
other side of which is water. As the products of combustion and the water to
which they impart heat are both at equal pressure, both being within the
boiler, the sides of the passages may be very thin.
The above-described methods may also be combined in various ways. A
pump or forcing apparatus may be employed to cause the water to circulate
through the passages. A regulating apparatus may be employed, so that when
the pressure in the boiler exceeds a certain point the supply of inflammable
fluid to the cylinder or vessel in which it is burnt is diminished, and thus less
beat is produced and less steam generated, while if the pressure falls below a
certain point the reverse action takes place. When combustion is caused to
take place within the boiler or evaporating vessel by the action of the engine
the first stroke of the engine cannot be caused in the same way as the strokes
when the engine is in regular action. For starting the engine in the first
instance heat may be applied externally to the boiler; or an explosive com-
pound or compounds which rapidly liberates gas may be introduced into the
working cylinder or into a vessel connected with this, the gases generated from
which cause the piston to move. After the engine has worked and the water

page_text: in the boiler or evaporating vessel has acquired heat, and the fluid in that
vessel has acquired pressure, then so long as this heat and pressure, or a
sufficient portion of them, are retained there is a stock of elastic force ready
to start the engine at any moment. If the surface of the boiler or vessel is
principally covered with materials which are bad conductors of heat then a
very small application of heat from the exterior will suffice to keep up the
heat and pressure within the vessel, and thus retain the stock of elastic force.
Similarly, if inflammable vapour, such as vapour of petroleum or of hydro-
carbons, is used as an ingredient of the inflammable mixture, when the
requisite heat and pressure has been attained in the vessel in which this
vapour has been generated it may be maintained by the application of a small
external heat. When the air employed is used at a high pressure a series of
pumps for the compression of the air may be employed, the first compressing
it to a certain degree of pressure, the next to a higher degree of pressure, and
so on. Water may be used for filling the cylinders of the pumps at the end
of the strokes, and the various constructions and materials which have been
used for valves in pumps used for compressing air may be employed. The
steam generated may be employed to perform work by acting as a blast, or in
numerous jets or blasts, forcing air along with itself into a vessel, the mixed
air and steam thus forced into the vessel being employed to move a piston in
a cylinder or perform work in an engine. When it is employed in this way
the air and steam, after their entrance into the vessel, may be heated by being
caused to pass through numerous tubes or passages, or in other ways, and by
this heat any steam which has been condensed may be reconverted into
steam, and if desired may be superheated. Instead of forcing air into a vessel
the blast or blasts of steam may force steam into a vessel, the steam thus
forced into the vessel being employed to perform work in an engine. Steam
which has been discharged from this engine after performing work may be
again driven by the blast of issuing steam into the vessel and again perform
work in the engine. The steam after its entrance into the vessel may be
subjected to heat, as previously described. Steam acting as above described
may be generated and superheated by beat applied in any manner desired.
When the products of combustion are employed to act externally on a
boiler the following construction may be employed:-Tubes are set within a
cylindrical vessel of the form of a locomotive boiler. Between the cylindrical
shell and the tubes is a curved partition. The space between the shell and
the partition becomes gradually narrower towards the bottom and wider
towards the top. This partition is pierced with holes or apertures, so that
water which has descended between the partition and the outer cylindrical

page_text: | shell can pass through these apertures and rise upwards through the interior
part of the boiler in which the tubes are placed. The water in the space
between the partition and the envelope of the boiler not being heated by the
tubes is constantly cooler and heavier than the fluid among the tubes where
the steam is generated, and thus a regular circulation is established, the water
constantly descending through the channel between the partition and the outer
envelope and rising upwards among the tubes. The widening of the channel
in the upper part allows the downward current of water to be formed without
interference from the ascending current. The circulation thus established
may be augmented by means of a pump or forcing apparatus, which constantly.
draws water from the upper part of the water in the boiler and forces it into
the space between the shell of the boiler and the partition in which it is
desired to maintain a descending current. When the form of the envelope of
the boiler is other than cylindrical a similar method may be employed.
The following is another form of boiler which may be used:-Tubes are
inserted in a vessel which may be cylindrical or may be of other forms. Within
these tubes are other tubes having openings at the bottom, so that water can
pass down the interior tubes and ascend in the space between the interior and
exterior tubes; these interior tubes enter a vessel. A pump or forcing appa-
ratus constantly draws the water from that part of the boiler which it enters'
after ascending through the spaces between the tubes, and forces it into
the vessel in which the interior tubes are inserted, thus causing constant.
circulation. The tubes are exposed to heat as in other cases. If it is desirable
that the gases which impart heat to them should be caused to move in a
direction opposite to that in which the water moves in the spaces between the
external and internal tubes, boilers constructed as above described may be
employed for general purposes. Whatever be the form of the boiler used, a
pump or forcing apparatus may always be employed to cause a circulation of
the water. In such a case some portion of the power of the engine is expended
in working the pump, but on the other hand the heating surface is rendered
more efficient, and the boiler can be made smaller and lighter. When tho
expansive force of heated products of combustion is used to perform work on
a piston in a cylinder, the water or cooling agency employed to keep the
cylinder cool abstracts heat from the gases while they are performing work,
and thus diminishes their expansive force, causing loss of power. In order to
obviate this it is desirable that the action of the gases while performing work
should be very rapid, so that the cooling agency of the water or other material
employed to cool the cylinder may have little time to abstract heat from the

page_text: gases while they are performing work.
With the view of effecting this the
expansive force of the gases may be employed to compress air or aeriform fluid
in a receiver, from which its return is prevented by valves. The air or fluid
thus compressed is used to produce motive power. The products of combustion
having performed work in driving the air into the receiver are afterwards
employed to heat water and generate steam. The steam so generated is
employed to perform work in an engine either conjointly with the compressed
air or separately, as desired...The charge. of inflammable mixture may act in
a cylinder, into which it is introduced. It may be introduced through
numerous passages; it may be in immediate contact with the air or fluid in
front of it, which it is desired to drive into the receiver; or it may be separated
from this by a piston, which piston is propelled by the expansive force of the
ignited mixture, and drives the air or fluid into the receiver. Again, a
moveable partition may be employed, which for a while separates the inflam-
mable mixture from the non-inflammable fluid; this partition being removed
just previous to the ignition of the mixture.. After the propulsive force of the
ignited mixture is spent and the air or fluid driven to the receiver, a piston is
caused to make a stroke in the cylinder, expelling the heated products of com-
bustion through an eduction valve, whence they pass to a passage or passages,
in traversing which they heat water and generate steam in a boiler or vessel.
On the return stroke of the piston a fresh charge of the inflammable mixture
and of the air or fluid to be compressed by it is introduced into the cylinder."
The charge of inflammable mixture and the air or non-inflammable fluid which
it compresses and drives into the receiver may be introduced into the cylinder
at the atmospheric pressure, or they may be introduced into it, at a high
pressure exceeding that of the atmosphere to any extent desired. When a
high pressure is used a larger portion of heat can be converted into work by
the expansion of the ignited inflammable mixture. The piston which is.
employed to move through the cylinder in order to expel the products of
combustion may be worked mechanically by the engine, or it may be worked
by means of the compressed air or fluid which has been forced into the
receiver by the expansive force of the ignited mixture. The steam generated
as previously described may be mixed with this compressed air or fluid. The
fluid thus acting on the piston may expand to the pressure at which it is
desired to use the charge, and on the return of the piston a portion of it may
enter the cylinder on the other side, thus introducing fluid into the cylinder to
be driven into the receiver by the ignited gases at the desired pressure. The
remaining portion may be compressed by the movement of the piston; this

page_text: compressed fluid re-expanding and performing work in the succeeding stroke.
The piston whilo pressed by the fluid may perform work on the engine, or it
may compress air which performs work on the engine. Again, fluid which
bas performed work in another cylinder and has expanded to the desired
pressure may be introduced into the cylinder for the purpose of being driven
into the receiver by the ignited charge of inflammable mixture. If the piston
is worked mechanically by the engine, products of combuction which have
been cooled by heating water and generating steam, but whose temperature is
still higher than that of the water in the boiler, may be employed.to enter the
cylinder behind the piston while it is advancing to expel the products of com-
bustion, and so to prevent internal cooling of the cylinder. at that stage of the
operation. When the piston has reached the confines of that part of the
cylinder which it is desired to fill with the inflammable mixture a partition
may be interposed between the part of the cylinder into which the charge is
introduced and the other part, so as to prevent intermixture of the fluids in
the two portions of the cylinder while the charge is being introduced. This
partition is removed just previous to the ignition of the inflammable mixture.
This partition may be formed of a plane or planes which slide in a direction
transverse to tho axis of the cylinder, or a revolving plane may be used
pierced by an excentric aperture, or a revolving, spherical piece may be
employed pierced with a cylindrical passage. By the revolution of this piece
tho axis of this cylindrical passage is sometimes made to coincide with the
axis of the cylinder, so as to allow free passage from one side of the cylinder
to the other, whilst sometimes it is brought into a position transverse to the
axis of the cylinder. Instead of a piston working in the cylinder a plunger
may be employed. Again, the piston which works in the cylinder may be
attached to a trunk of smaller diameter than itself. In this case the products
of combustion after they have been discharged at one end of the cylinder and
have been cooled by heating water and generating steam may re-enter the
cylinder of the other end, filling the annular space around the trunk. The
piston on which the fluid at high pressure acts may be attached to the samo
trunk working in a separate cylinder. When this method of construction is
employed, if the pressure of the beated products of combustion after their
expansion is reduced below the atmospheric pressure the contraction of volume
which the heated gases undergo when they heat water and cause steam to be
generated becomes utilized as a source of power.
The various different modes of construction which have been previously
described with reference to the gas engine may be used to produce the same

page_text: air enter the cylinder & in proportions regulated by the cocks or valves through
which they pass, and mingle therein, and insulated electric wires being fitted.
through the end of the cylinder, as represented at c', the mixture is inflamed
by a spark when the plunger 6' has nearly reached the end of its stroke; d is.
another valve opening outwards from the cylinder b, and communicating with
a pipe d', perforated with numerous holes and immersed in the water of the
boiler a, so that on the ignition of the gaseous mixture in the cylinder 6 and
the return of the plunger b¹, the hot and expanded products of combustion
pass through the valve d and bubble through the water in a, thereby
generating steam, together with which they occupy the space above the water
in a; e is a pipe leading from the steam space in a to the jacket of a slide f
fitted on a cylinder g. The pipe e may be fitted with a stop-cock or shut-off
valve, also with a throttle valve controlled by a governor in the ordinary way,
so as to regulate the speed and power of the engine, of which forms the
supply pipe. The cylinder g is fitted with a trunk piston g, baving a larger
annular surface on the one side than on the other, and this, by means of a
connecting rod h, works a crank j in the usual way. The slidef (which is
represented at half-stroke) is worked by an excentric or cam with the necessary
weigh shaft and rods from the crank shaft, and it is so constructed that when
it is at or near one end of its stroke the mixed steam and products of com-
bustion enter the front end of the cylinder 9, and press upon the smaller
annular area (which is nevertheless larger than the area of the plunger 6'),
while the contents of the other end of the cylinder issue by the eduction
passage k, and that when the slide f is at or near the other extreme of its
stroke the supply from e and also the eduction passage & are cut off, and the
steam and gases contained in the front or end of the cylinder 7 pass through.
the ports and the D-shaped hollow of the slide to the back or larger end of
the cylinder, wherein they expand. The excentric, cam, or other apparatus.
for working the slide f, and also that for producing the electric spark in the
cylinder b, being properly set or timed with respect to the crank j, the
action of the apparatus is as follows:-The steam and gases passing from the
front or smaller end of the cylinder g press on the larger annular area bebind,
and thus force the piston g' forward, and this withdraws the plunger b', so
that the cylinder b becomes charged with inflammable gaseous mixture entering
by the valves in the cover c. When the piston 9' and plunger & have nearly
attained the forward extreme of their stroke the slide f changes the com-
munication of the parts, and the mixture in b is ignited. The mixed steam
and gases pass from a by the pipe e, enter the front part of the cylinder 9, and

page_text: described.
pressing on the front annular area of the piston g', which exceeds the area of
tho plunger b', force the piston g' and plunger & back, driving out the expanded
steam and gases which have performed work through the eduction passage k,
and driving the products of combustion from the cylinder b through the valve d
into the passage d', whence they pass through the water in a, as already
It may be readily understood that as the front annular area of
the piston g' exceeds the area of the plunger 6, and as the back annular area
of g¹ exceeds the front annular area of the same, there is an excess of pressure
on the piston 'g in both directions of its motion, and this excess of pressure,
transmitted through the connecting rod h to the crank j, constitutes the moving
force of the engine.
Although for the sake of simplicity the piston g' and the plunger are
represented as in the Drawing on one axis and moving together, and although
by this arrangement the moving pressure is exerted on the annular areas of
the piston g', the cylinder 9 might be separated from b, and placed by the
side of 6, or in any other convenient position, and instead of a trunk piston g³
there might be one or more simple pistons working in one or more cylinders;
and these, as well as the plunger b', might be connected with separate cranks
on a common shaft, so as all to move in accord, the same action being never-
theless maintained as that which has been described above.
Figure 2 of the accompanying Drawings represents a longitudinal section
of a horizontal trunk compound gas and steam engine constructed according
to my Invention, wherein the air with gas or inflammable vapour instead of
being ignited after mixture, as described in reference to Figure 1, is ignited
during mixture. As a large part of this apparatus is like that represented in
Figure 1 it is unnecessary to describe it again, I will therefore describe only
the points in which the two arrangements differ. On referring to the
description of Figure 1 it will be seen that there is a cylinder b, to which air
and gas or inflammable vapour are admitted, and wherein they are ignited
after mixture. Instead of this, in the plan now represented I employ an
annular cylinder 2, and add another cylinder m, worked by a plunger extended
backwards from the piston. The cylinder is supplied with air by a pipen fitted
with a valve, and the cylinder m is supplied with gas or inflammable vapour
by a pipe o, also fitted with a valve. The annular area of and the circular
area of m are made in such proportions as to give the proper quantities of the
ingredients for combustion. I prefer to supply both the air and the gas or
inflammable vapour under a pressure of several atmospheres; and I do this
by connecting the respective supply pipes n and o with compressing pumps

page_text: made in the proper proportions and worked by cranks or excentrics from the
engine shaft. I do not represent these pumps, as they may be constructed
and worked in any convenient manner, such as is generally adopted for com-
pressing gaseous fluids. After the cylinders and m have been respectively
filled with their charges the return of the plungers in those cylinders drives
their contents past valves at p and q into a chamber r, on entering which they.
mix together, and are ignited by a voltaic spark or other convenient means.
Though the Drawing represents only one engine, it may be readily understood
that two, three, or more can be placed side by side, working on the same crank
shaft, and that thus a continuous supply of air and inflammable fluid can be
sent into the chamber r, so that the stream being once ignited continues to burn
without fresh kindling during the working of the engines. The products of
combustion in pass through numerous holes perforated in the lower part of
the chamber, and bubble up through the water in the boiler a, which surrounds
the combustion chamber r. The steam thus generated, mingled with products
of combustion in the space above the water in a, passes by the pipe e, as
already described, to the engine, the parts of which are indicated by the same
letters as those in Figure 1, and may be understood from the description
already given of that Figure. In this arrangement as in that represented
in Figuro 1, instead of employing trunk or annular pistons combined on one
axis, separato pistons working in separate cylinders, and connected with
separate cranks on one shaft, may be used, and a separate cylinder may be
used for expansion, as in Woolf's engine. The products of combustion may
also be caused to act on the water in the boiler and generate steam in various
ways, as already described, and the inflammable gas may also be of various
kinds, such as hydrocarbons or the products arising from the partial com-
bustion of carbonaceous fuel, or from the action of steam on incandescent
fuel, and oxygen may be used instead of air.
Figure 3 of the accompanying Drawings represents a longitudinal section
of an apparatus constructed according to my Invention, whereby a jet of steam
issuing from a vessel containing steam at high pressure is made to force
steam along with itself into a vessel in which steam is contained at lower
pressure, the steam in this latter vessel being used to produce motive power,
and thus the expansion of very high pressure steam may be utilized without
the inconvenience arising from great variation of pressure on a piston. a is a
vessel containing steam at high pressure, which issues in a jet through the
nozzle c within the vessel b, to which steam at lower pressure is supplied
through the pipe f. The steam issuing from the nozzle c forces steam along

page_text: with itself into the passage d, and this current of steam creates a pressure in
the vessel e lower than that in the vessel a. The steam in the vessel e passes
off by the pipe 9 to a cylinder, in which it works a piston; or it may be
employed to produce motive power in other ways. Thus a supply of steam is
obtained for the production of motive power lower in pressure but larger in
quantity than the supply in the vessel a. The vessel is supplied by the
pipe with steam which has been discharged from the engine after performing
work, and which may be at any pressure lower than that in the vessel 6. The
steam in the vessel a may be superheated, and the steam propelled into the
vessel may also be superheated before it enters the cylinder or other
apparatus for producing motive power. Instead of thero being only one
nozzle c from the vessel a, and one passage d from the vessel 6 to the vessel e
there may be several of those acting simultaneously.
Figure 4 of the accompanying Drawings represents the transverse section
of a tubular boiler wherein the circulation of water. is assisted by diapragms
introduced into the boiler to separate opposing currents. The tubes are
arranged so as to leave some clear space on either side of the barrel of the
boiler, and, a diaphragm or partition a is placed near the tubes at each side.
leaving a clear space or channel, between it and the cylindrical side of the
boiler. The water heated by the tubo surface ascends through the spaces
between the tubes, and its current is supplied by a corresponding descent of
water on each side in the channels formed between the diaphragms a, a, and
the sides of the boiler, as indicated by the arrows. The diaphragms a, a,
may if desired be carried entirely round the lower part of the barrel beneath
tho tubes, so as to form one continuous diaphragm, its lower portion being
perforated with numerous holes. Generally, however, this is not necessary,
as the tubes form interruptions to the free passage of the water, which is
thereby caused to ascend in the free spaces between them.
Figure 5 of the accompanying Drawings represents a transverse section of
a tubular boiler in which circulation of the water is effected by mechanical
means according to my Invention. a is a pipe extending longitudinally along
the boiler, perforated with numerous holes, and communicating at either end
with a pipe b, which leads to a channel c extending longitudinally along the
under side of the boiler. In any convenient part of the pipe 6 a pump or
other propelling apparatus is arranged, so as to cause the water to flow in the
direction indicated by the arrows. The water is thus forced to enter tho
lower part of the boiler by the channel c, and to rise through the spaces
between the boiler flues, receiving beat as it passes and giving off bubbles of

page_text: steam. It is collected again in the pipe a, and returns through 6 to be
circulated again.
Although I have represented this arrangement in connection with a tubular
boiler, it can be applied to a flue or other boiler in a similar manner, as may
be readily understood, the object being to maintain a circulation of water over
or along the heated surfaces, so that every portion may successively receive
heat therefrom.
Figure 6 of the accompanying Drawings represents a section of part of a
boiler constructed according to my Invention, with tubes closed at the bottom,
and circulation of the water effected therein by mechanical power. a is the
smoke or flame chamber or part of the flue; b, b, are tubes closed at bottom
projecting down into the chamber or flue a; c, c, are smaller tubes open at
bottom, the lower portions of which are placed within the tubes b, b, while
their upper ends communicate with a chamber d; within the boiler e is a
tube or channel forming a communication from the water space to the
chamber d, and at any convenient point in the tube a pump or other
apparatus is applied to cause the water to flow in tho direction indicated by
Thus the water is caused to descend the smaller or inner
tubes c, c, and to ascend the outer tubes 6, 6, and the water space f, each
successivo portion thus receiving heat.
the arrows.
:
Figure 7 of tho accompanying Drawings represents a longitudinal section
of an apparatus constructed according to my Invention, whereby the com-
bustion of inflammable gas or vapour with air or oxygen is caused to com,
press air in a receiver, the air so compressed being used for producing motive
power. a is a cylinder made in two parts, and fitted with a piston a', worked
by a rod from a cam, crank, or excentric on any convenient moving part of
the engine to which the apparatus is connected. In the faces of the flanges
by which the two parts of the cylinder a are connected together channels are
formed separated by an annular diaphragm 6 with a sharp inner edge, and
the two parts of the cylinder a are kept a very small distance apart, so as to
afford a narrow passage or slit communicating from the channels on each side
of 6 to the interior of the cylinder a. On the cylinder a is placed a slide c,
and ports are formed connecting D passages of the slide with one end of the
cylinder a, and with the channels on each side of the partition or diapragm b.
Of these parts, d communicates with a vessel or pipe supplying inflammable
gas or vapour, which may be at high pressure; e communicates with the
atmosphere, or with a vessel containing air under pressure or oxygen;
f communicates with tho flues or tubes of a boiler. The slide, which is

page_text: represented at half stroke, is worked to and fro by a cam, excentric, or other
convenient means. 9 is a vessel or receiver communicating by a pipe h with
a cylinder or other apparatus wherein gaseous fluid under pressure is employed
to produce motive power; is a valve separating the receiver 9 from the
cylinder a, and opening inwards into the receiver g. I prefer to construct
this valve in the manner represented in the Drawing, a front elevation of the
valve being shown in Figure 8. The seating of the valve is a grating, con-
sisting of a plate or diaphragm perforated by numerous radiating slots, and
over each of those slots is laid a strip of steel plate or other elastic material;
m is a guard to prevent the elastic strips from being forced too far back when
the valve opens. The radiating strips may be all formed in one sheet of
material cut out to the proper form, and held by a bolt or screw at the centre
of the diaphragm, which also serves to secure thereto the guard m. The
action of the apparatus is as follows:-The piston a¹ being at the end of the
cylinder next the valve 1, the slide is moved to such a position that the air
supply é communicates with the port leading to the end of the cylinder next
to l, and the other ports and passages are closed. As the piston a' is drawn
back air enters by this port behind it and fills the cylinder a until the front of
the piston reaches the slit which separates the two ports of the cylinder. The
slide is then moved so as to close the passage by which air previously entered
the cylinder, and to make a communication for air from e to one of the
channels at the diaphragm b, and for inflammable gas or vapour from d to the
other channel at b. The quantities of air and inflammable gas or vapour that
enter by those passages aro regulated by stop-cocks or valves on their re-
spective supplies e and d. As the piston is still farther drawn back, the part
of the cylinder a beyond the slit is charged with the air and inflammable fluid,
which are mingled in passing. through the slit at b. When the piston has
reached the end of the cylinder the slide is moved so as to close all the ports,
and the inflammable mixture is ignited by an electric spark or other con-
venient means. The mixture being suddenly expanded by combustion propels
the air contained in a through the valve into the receiver 9. When the
propulsive force is reduced to, a certain point the valve 1 closes and prevents
the return of the air thus driven into the receiver. The slide is then moved
so as to uncover the passage leading from the end of the cylinder, and the
piston a' being pushed back the bot products of combustion issue by that
passage, and are conducted by the pipe f to the flues of a boiler, in passing
through which they generate steam. When the piston has reached the end
of the cylinder the operation is repeated, and so on continuously, each with:

page_text: drawal of the piston charging part of the cylinder with air and part with
inflammable gaseous matter, the combustion of that matter propelling the
successive charges of air into the receiver g, and the products of combustion
being successively conveyed to the flues of a boiler and generating steam.
The air compressed into the receiver g and also the steam generated in the
boiler may be used in a cylinder of ordinary construction, or in any other
suitable apparatus for producing motive power from fluids under pressure.
The cylinder a may be surrounded with water, and thus enclosed within a
portion of the boiler (like the cylinder b in Figure 1), so that the heat pro-
duced by the successive combustions in a may be moderated and given to the
water in the boiler, being tbus utilized in the generation of steam.
Having thus described the nature of my Invention, and in what manner
the same is to be performed, I would have it understood that I do not limit
myself to the details of construction represented in the Drawings; but
I claim,
First, tho modes herein described of constructing engines in which a
mixture of gas and air or other inflammable matter is ignited, and the pro-
ducts of combustion are caused to pass into the interior of a boiler or
evaporating chamber and act along with the steam to produce motive power.
Second, the employment of a jet or blast of steam, or of several such jets
or blasts issuing from a vessel in which steam is contained at high pressure,
to drive steam along with itself into a vessel in which steam is contained at
lower pressure, the steam from the latter vessel being employed to produce
motive power, and the steam discharged from the engine being used to supply
the steam forced into the vessel.
Third, the mode herein described of applying partitions or diaphragms to
boilers for promoting the circulation of the water therein.
Fourth, the modes herein described of forcing the circulation of water in
boilers by means of a pump or other propelling apparatus.
Fifth, the employment as herein described of the propulsive force of an
ignited inflammable mixture to drive air into a vessel in which it is contained
under pressure, and whence it is taken to act on a piston or otherwise to
produce motive power.
Sixth, and the combination of this arrangement with a boiler in which
steam is generated by the discharged products of combustion, the steam thus
generated being used for the production of motive power.
Seventh, the combination of a vacuum engine in which a partial vacuum is
produced by the propulsive force of an ignited inflammable mixture with a

page_text: boiler in which steam is generated by the products of combustion, and the
mode described of utilizing the contraction of volume which those products
undergo in generating steam as a source of motive power.
In witness whereof, I, the said Matthew Piers Watt Boulton, have here-
unto set my hand and seal, this Sixth day of September, in the year
of our Lord One thousand eight hundred and sixty-six.
M. P. W. BOULTON. (L.S.)