Year: 1887

page_text: We, ARTHUR GEORGE MUMFORD, of Culver Street Iron Works, Colchester in
the county of Essex, Engineer, and ALFRED ANTHONY of the aforesaid works
Draughtsman do hereby declare the nature of this said invention to be as follows:-
Our invention relates to an improved engine be worked by steam or other fluid,
in which we attain a simplification and reduction of the working parts, and increased
efficiency.
We use two cylinders placed side by side, or otherwise in close proximity to each
other. In each cylinder is a piston which is made hollow and of a length slightly
exceeding half the total length of the bore of the cylinder, for a purpose that will
hereinafter be made apparent.
The pistons are provided with suitable piston rings at each end, and are prevented
from revolving in their cylinders by a key or its equivalent in the cylinder engaging
with a featherway or its equivalent in the piston, or vice versa. Steam is admitted into
the cylinders from a steam chest common to both, through suitable slots and holes
formed in the cylinders and pistons respectively, in such a manner as to admit steam
during the whole or any desired portion of the stroke.
In the centre of the length of each cylinder and preferably on the lower side thereof
are formed three longitudinal ports. The centre one of each set is an exhaust port
which communicates with an exhaust chamber common to both cylinders. The other
two ports of each set are steam ports and communicate by suitable passages with the
ends of the other cylinders respectively, that is to say, the ports in one cylinder
communicate with the ends of the other cylinder, and rice versa.
On the outer side of each piston and at each end thereof, is a longitudinal groove
or channel formed by casing in a portion of the interior of the piston in order that the
said groove or channel shall have a sectional area not less than that of the steam ports.
The width of each of these grooves or channels is sufficient to open one of the steam
ports to the exhaust port, the groove or channel at one end of the cylinder forming
the communicating passage between the exhaust port and the one steam port, and the
groove or channel at the other end of the cylinder forming the communicating passage

page_text: "
between the exhaust port and the other steam port. Along side each groove or channel
a slot is cut through the wall of the piston to allow the steam in the cylinders to get
access to the steam ports with which they coincide at such times as the grooves or
channels are opening the exhaust port to the other steam port. It will be understood
that both pistons are constructed alike, and that as the length of each exceeds balf
the length of the cylinder, the ports are never uncovered to either end of the
cylinder.
Each piston is fitted with a piston rod of the usual type which passes out through
the cover or end of the cylinder by a stuffing box of the usual construction.
When steam is admitted into the pistons it enters that hole in each piston which is
opposite to one of the ports in its cylinder, and thus passes to one end of the other
cylinder causing each piston respectively to make a stroke. This immediately
reverses the direction of the steam causing it to pass through the other opening in
each piston and port in each cylinder to the opposite end of each cylinder, which
causes the pistons to return, and the same cycle of operations is continuously repeated
while the engine is working.
Our invention may be applied to any purpose for which power is required. It may
be used in conjunction with a pump as a direct acting pumping engine, or it may be
coupled to a crank shaft by connecting rods or equivalent devices, and form an engine
suitable for any purpose requiring motive power.
When it is used as a direct acting pumping engine suitable cushioning is provided
at each end of the cylinders by causing the pistons to travel a given distance beyond
the steam passages, and by providing at each end of each cylinder a very small orifice
or auxiliary port for the escape of the steam imprisoned behind the pistons, the
said auxiliary ports also serving for the readmission of live steam to the backs of the
pistons.
The arrangement of cylinders, pistons, and ports, herein before described may also
be used as a double pump for pumping water and other fluids.
101
1007
ROBT. ED. PHILLIPS, M.I.M.E.,
Royal Courts Chambers,
70-72, Chancery Lane, London, W.C.,
Agent for the Applicants.

page_text: We, ARTHUR GEORGE MUMFORD of the Culver Street Iron Works, Colchester in
the county of Essex Engineer, and ALFRED ANTHONY of the aforesaid works,
Draughtsman, do hereby declare the nature of this invention and in what manner
the same is to be performed to be particularly described and ascertained in and by the
following statement :-
Our invention relates to an improved engine to be worked by steam or other fluid,
in which we attain a simplification and reduction of the working parts and increased
efficiency.
We use two cylinders placed side by side, or otherwise in close proximity to each
other. In each cylinder is a piston which is made hollow, and of a length slightly
exceeding half the total length of the bore of the cylinder, for a purpose that will
hereinafter be made apparent.
The pistons are provided with suitable piston rings at each end, and are prevented
from revolving in their cylinders by a key or its equivalent in the cylinder engaging
with a featherway or its equivalent in the piston or vice-versa. Steam is admitted into
the cylinders from a steam chest common to both, through the pistons by means of
suitable slots and holes formed in the cylinders and pistons respectively, the steam
being admitted to both pistons continuously throughout their reciprocations.
In the centre of the length of each cylinder, and preferably on the lower side
thereof, are formed three longitudinal ports. The centre one of each set is an exhaust
port which communicates with an exhaust chamber common to both cylinders. The
other two ports of each set are steam ports and communicate by suitable passages with
the ends of the other cylinders respectively, that is to say the ports in one cylinder
communicate with the ends of the other cylinder, and vice versa.
On the outer side of each piston and at each end thereof, is a longitudinal groove
or recess formed by casing in a portion of the interior of the piston in order that the
said groove or recess shall have a sectional area not less than that of the steam ports.
The width of each of these grooves or recesses is sufficient to open one of the steam
ports to the exhaust port, the groove or recess at one end of the cylinder forming the
communicating passage between the exhaust port and the one steam port, and the
groove or recess at the other end of the cylinder forming the communicating passage
between the exhaust port and the other steam port. Along side each groove or recess
a slot or port is cut through the wall of the piston to allow the steam in the pistons to
get access to the steam ports in the cylinders with which they coincide at such times
as the grooves or recesses are opening the exhaust ports to the other steam ports. It
will be understood that both pistons are constructed alike, and that as the length of
each exceeds half the length of the cylinder the ports are never uncovered to either
end of the cylinder. Each piston is fitted with a piston rod of the usual type which
passes out through the cover or end of the cylinder by a stuffing box of the usual
construction.
When steam is admitted into the pistons it enters that slot or port in each piston
which is opposite to one of the ports in its cylinder and thus passes to one end of the
other cylinder causing each piston respectively to make a stroke. This immediately
reverses the direction of the steam causing it to pass through the other slot or port in
each piston, and port in each cylinder, to the opposite end of each cylinder which

page_text: causes the pistons to return, and the same oycle of operations is continuously repeated
while the engine is working, each piston acting as a distributing valve to the cylinder
in which the other piston works.
Our invention may be applied to any purpose for which power is required. It may
be used in conjunction with a pump as a directing-acting pumping engine, or it may
be coupled to a crank shaft by connecting rods or equivalent devices, and form an
engine, suitable for any purpose requiring motive power.
When it is used as a direct-acting pumping engine suitable cushioning is provided
at each end of the cylinders by causing the pistons to travel a given distance beyond
the steam passages, and by providing at each end of each cylinder a very small orifice
or auxiliary port for the escape of the steam imprisoned behind the pistons, the said
auxiliary ports also serving for the readmission of live steam to the backs of the
pistons. Small holes are also provided in the pistons in advance of the slots or ports
to admit the steam within the pistons to the ports in the cylinders, to facilitate starting
the pistons in any position.
In order that our invention may be fully understood we append hereto drawings
illustrating it, and showing how it may be carried into practical effect. In these
drawings Figure 1 is a sectional side elevation through one of the cylinders. Figure 2
is a sectional plan through the centre of the cylinders. Figure 3 is a transverse
section through the centre ports of the cylinders and Figures 4 and 5 are views of the
piston, the former showing the steam slots or ports and exhaust grooves or recesses,
and the latter showing the slot for the admission of steam within the piston and the
slot or keyway to receive the key to prevent the rotation of the piston.
Throughout the several views similar parts are marked with like letters of
reference.
Referring to the Figures. A and A¹, designate the cylinders which are preferably
cast in one piece and are fitted with covers A2, A2 back and front, the latter being
fitted with stuffing boxes and glands of the usual construction. B and B¹ designate
the hollow pistons fitted with piston rods B2, B3 which pass out through the stuffing
boxes on the cover A². C designates the steam chamber common to both cylinders A
and A', from which the steam or other fluid is admitted into the hollow pistons B
and B' by means of the holes c and c¹ in the cylinders and the slots 6 and 6' in the
pistons. D designates the exhaust chamber common to both cylinders, and in
communication therewith by the ports d and d¹. A3 and A³ designate the keys or
their equivalents, which engage with slots B³ and B³ or their equivalents, to prevent
the rotation of the pistons. E and E designate the slots or ports in the piston B,
and E and E¹ designate the slots or ports in the piston B₁ to admit the steam therein
to the ports e and e of the cylinder A, and the ports e¹ and e¹ of the cylinder A',
respectively. F and F designate the grooves or recesses in the piston B, and F" and Fi
designate the grooves or recesses in the piston B¹, to connect the ports e and e with
the exhaust port d, and the ports e¹ and e¹ with the exhaust port d', respectively.
e, e etc. designate the small auxiliary starting holes in the pistons, and e³, e etc.
designate the auxiliary ports connecting the ports e and e¹ with the ends of the
cylinders A and A', to provide suitable cushioning for the pistons, and facilitate their
reversal when the pistons are not coupled or connected up to a crank shaft.
It will be understood that when the pistons are coupled up or connected with a
crank shaft to form a motor engine, the auxiliary starting holes e², e³ etc., and the
auxiliary ports e³, e³ etc. may be dispensed with.
The action of our improved engine is as follows:-Supposing the pistons to be in
the position shown by Figure 2 of the accompanying drawing, the steam or other
fluid (which it will be understood is constantly admitted to the interior of both of the
hollow pistons by means of the holes c and c¹ and the slots 6 and 6¹) passes out of
the piston
through the rear slot or port E to the port e¹, and thence to the rear end
of the cylinder A¹, impelling the piston B¹ forward, the steam in the forward end of
the cylinder A exhausting through the port e¹ at the forward end of the cylinder A',
and thence by means of the rear groove or recess F in the piston B, through the
exhaust port d, to the exhaust chamber D. In the position shown by Figure 2. the

page_text: piston B¹ has moved forward so far that the rear slot or port E' of the piston B₁ has
just commenced to coincide with the porte of the cylinder A', thus admitting steam
to the front end of the cylinder A through the port e, the steam in the rear end of the
cylinder A exhausting through the port e at the rear end of the cylinder, and thence
by means of the rear groove or recess F¹ in the piston B₁, through the exhaust port d¹
to the exhaust chamber D. As the piston B² approaches the front end of the
cylinder A¹ the piston B is being impelled towards the rear end of the piston A,
so that by the time the piston B' reaches the end of its stroke, the piston B has moved
so far towards the rear end of the cylinder A as to open the front groove or recess F
and the front steam slot or port E to the exhaust port d and steam ports e¹ and e¹,
providing for the admission of steam in front of the piston B', and for the exhausting
of the steam in the rear thereof.
This cycle of operations continues so long as steam is admitted to the chamber C,
the one piston acting as a distributing valve to the cylinder containing the other
piston continuously throughout its stroke, and vice versa, so that neither piston is at a
state of rest whilst the engine is in motion.
It will be understood that the sizes of the various openings or ports may be varied.
to give a greater or less "cut off" as found necessary or desirable.
It will be seen that both pistons are alike at either end, so that they may be reversed,
or interchanged, and also that they are fitted with expansion rings at each end.
We are aware that duplex engines and pumps have already been made in which
each piston acts as a distributing valve to the other cylinder, and therefore we do not
broadly claim such as our invention, but having now particularly described and
ascertained the nature of our said invention, and in what manner the same is to be
performed, we declare that what we claim is :-
1. In a steam engine having duplex cylinders and hollow pistons, the latter acting
as distributing valves to the foriner; the particular arrangement of openings or ports,
and grooves and recesses, for admitting and exhausting the steam to and from the
alternate cylinders, whereby a uniform reciprocating motion is imparted to the two
pistons, enabling them to be coupled to a crank shaft as set forth.
2. In a steam engine having duplex cylinders, with one steam and one exhaust
chamber common to both cylinders, and having hollow pistons acting as distributing
valves; the auxiliary steam holes e², e² etc. to facilitate starting the pistons in any
position, as set forth.
3. In a steam engine having duplex cylinders and hollow pistons, the latter acting
as distributing valves to the former; the combination with the said pistons and
cylinders, of the auxiliary starting holes et, e³ etc., and the cushioning ports e³, e³ etc. as
set forth.

page_text: Date of Application, 18th Oct., 1987
Complete Specification Left, 25th June, 1888
Complete Specification Accepted, 3rd Aug., 1883
We, ARTHUR GEORGE_MUMFORD, of the Culver Street Iron Works, Colchester in
the county of Essex, Engineer, and ALFRED ANTHONY of the aforesaid works
Draughtsman do hereby declare the nature of this said invention to be as follows:-
Our invention relates to an improved engine to be worked by steam or other fluid
in which we attain a simplification and reduction of the working parts, and increased
efficiency.
We use two cylinders placed side by side, or otherwise in close proximity to each
other. In each cylinder is a piston which is made hollow and of a length slightly
exceeding half the total length of the bore of the cylinder, for a purpose that will
hereinafter be made apparent.
The pistons are provided with suitable piston rings at each end, and are prevented
from revolving in their cylinders by a key or its equivalent in the cylinder engaging
with a featherway or its equivalent in the piston, or vice versa. Steam is admitted into
the cylinders from a steam chest common to both, through suitable slots and holes
formed in the cylinders and pistons respectively, in such a manner as to admit steam
during the whole or any desired portion of the stroke.
In the centre of the length of each cylinder and preferably on the lower side thereof
are formed three longitudinal ports. The centre one of each set is an exhaust port
which communicates with an exhaust chamber common to both cylinders. The other
two ports of each set are steam ports and communicate by suitable passages with the
ends of the other cylinders respectively, that is to say, the ports in one cylinder
communicate with the ends of the other cylinder, and vice versa.
On the outer side of each piston and at each end thereof, is a longitudinal groove
or channel formed by casing in a portion of the interior of the piston in order that the
said groove or channel shall have a sectional area not less than that of the steam ports.
The width of each of these grooves or channels is sufficient to open one of the steam
ports to the exhaust port, the groove or channel at one end of the cylinder forming
the communicating passage between the exhaust port and the one steam port, and the
groove or channel at the other end of the cylinder forming the communicating passage

page_text: between the exhaust port and the other steam port. Along side each groove or channel
a slot is cut through the wall of the piston to allow the steam in the cylinders to get
access to the steam ports with which they coincide at such times as the grooves or
channels are opening the exhaust port to the other steam port. It will be understood
that both pistons are constructed alike, and that as the length of each exceeds half
the length of the cylinder, the ports are never uncovered to either end of the
cylinder.
Each piston is fitted with a piston rod of the usual type which passes out through
the cover or end of the cylinder by a stuffing box of the usual construction.
When steam is admitted into the pistons it enters that hole in each piston which is
opposite to one of the ports in its cylinder, and thus passes to one end of the other
cylinder causing each piston respectively to make a stroke. This immediately
reverses the direction of the steam causing it to pass through the other opening in
each piston and port in each cylinder to the opposite end of each cylinder, which
causes the pistons to return, and the same cycle of operations is continuously repeated
while the engine is working.
Our invention may be applied to any purpose for which power is required. It may
be used in conjunction with a pump as a direct acting pumping engine, or it may be
coupled to a crank shaft by connecting rods or equivalent devices, and form an engine
suitable for any purpose requiring motive power.
When it is used as a direct acting pumping engine suitable cushioning is provided
at each end of the cylinders by causing the pistons to travel a given distance beyond
the steam passages, and by providing at each end of each cylinder a very small orifice
or auxiliary port for the escape of the steam imprisoned behind the pistons, the
said auxiliary ports also serving for the readmission of live steam to the backs of the
pistons.
The arrangement of cylinders, pistons, and ports, hereinbefore described may also
be used as a double pump for pumping water and other fluids.
1000
ROBT. ED. PHILLIPS, M.I.M.E.,
Royal Courts Chambers,
70-72, Chancery Lane, London, W.C.,
Agent for the Applicants.

page_text: Improvements in Steam or other Fluid Engines and Pumps.
We, ARTHUR GEORGE MUMFORD of the Culver Street Iron Works, Colchester in
the county of Essex Engineer, and ALFRED ANTHONY of the aforesaid works,
Draughtsman, do hereby declare the nature of this invention and in what manner
the same is to be performed to be particularly described and ascertained in and by the
following statement :-
Our invention relates to an improved engine to be worked by steam or other fluid,
in which we attain a simplification and reduction of the working parts and increased
efficiency.
We use two cylinders placed side by side, or otherwise in close proximity to each
other. In each cylinder is a piston which is made hollow, and of a length slightly
exceeding half the total length of the bore of the cylinder, for a purpose that will
hereinafter be made apparent.
The pistons are provided with suitable piston rings at each end, and are prevented
from revolving in their cylinders by a key or its equivalent in the cylinder engaging
with a featherway or its equivalent in the piston or vice-versa. Steam is admitted into
the cylinders from a steam chest common to both, through the pistons by means of
suitable slots and holes formed in the cylinders and pistons respectively, the steam
being admitted to both pistons continuously throughout their reciprocations.
In the centre of the length of each cylinder, and preferably on the lower side
thereof, are formed three longitudinal ports. The centre one of each set is an exhaust
port which communicates with an exhaust chamber common to both cylinders. The
other two ports of each set are steam ports and communicate by suitable passages with
the ends of the other cylinders respectively, that is to say the ports in one cylinder
communicate with the ends of the other cylinder, and vice versa.
On the outer side of each piston and at each end thereof, is a longitudinal groove
or recess formed by casing in a portion of the interior of the piston in order that the
said groove or recess shall have a sectional area not less than that of the steam ports.
The width of each of these grooves or recesses is sufficient to open one of the steam
ports to the exhaust port, the groove or recess at one end of the cylinder forming the
communicating passage between the exhaust port and the one steam port, and the
groove or recess at the other end of the cylinder forming the communicating passage
between the exhaust port and the other steam port. Along side each groove or recess
a slot or port is cut through the wall of the piston to allow the steam in the pistons to
get access to the steam ports in the cylinders with which they coincide at such times
as the grooves or recesses are opening the exhaust ports to the other steam ports. It
will be understood that both pistons are constructed alike, and that as the length of
each exceeds half the length of the cylinder the ports are never uncovered to either
end of the cylinder. Each piston is fitted with a piston rod of the usual type which
passes out through the cover or end of the cylinder by a stuffing box of the usual
construction.
When steam is admitted into the pistons it enters that slot or port in each piston
which is opposite to one of the ports in its cylinder and thus passes to one end of the
other cylinder causing each piston respectively to make a stroke. This immediately
reverses the direction of the steam causing it to pass through the other slot or part in
each piston, and port in each cylinder, to the opposite end of each cylinder which

page_text: causes the pistons to return, and the same cycle of operations is continuously repeated
while the engine is working, each piston acting as a distributing valve to the cylinder
in which the other piston works.
Our invention may be applied to any purpose for which power is required. It may
be used in conjunction with a pump as a directing-acting pumping engine, or it may
be coupled to a crank shaft by connecting rods or equivalent devices, and form an
engine, suitable for any purpose requiring motive power.
When it is used as a direct-acting pumping engine suitable cushioning is provided
at each end of the cylinders by causing the pistons to travel a given distance beyond
the steam passages, and by providing at each end of each cylinder a very small orifice
or auxiliary port for the escape of the steam imprisoned behind the pistons, the said
auxiliary ports also serving for the readmission of live steam to the backs of the
pistons. Small holes are also provided in the pistons in advance of the slots or ports
to admit the steam within the pistons to the ports in the cylinders, to facilitate starting
the pistons in any position.
In order that our invention may be fully understood we append hereto drawings
illustrating it, and showing how it may be carried into practical effect. In these
drawings Figure 1 is a sectional side elevation through one of the cylinders. Figure 2
is a sectional plan through the centre of the cylinders. Figure 3 is a transverse
section through the centre ports of the cylinders and Figures 4 and 5 are views of the
piston, the former showing the steam slots or ports and exhaust grooves or recesses,
and the latter showing the slot for the admission of steam within the piston and the
slot or keyway to receive the key to prevent the rotation of the piston.
Throughout the several views similar parts are marked with like letters of
reference.
Referring to the Figures. A and A¹, designate the cylinders which are preferably
cast in one piece and are fitted with covers A2, A2 back and front, the latter being
fitted with stuffing boxes and glands of the usual construction. B and B designate
the hollow pistons fitted with piston rods B2, B2 which pass out through the stuffing
boxes on the cover A². C designates the steam chamber common to both cylinders A
and A', from which the steam or other fluid is admitted into the hollow pistons B
and B by means of the holes c and c¹ in the cylinders and the slots and b¹ in the
pistons. D designates the exhaust chamber common to both cylinders, and in
communication therewith by the ports d and d¹. A3 and A³ designate the keys or
their equivalents, which engage with slots B3 and B3 or their equivalents, to prevent
the rotation of the pistons. E and E designate the slots or ports in the piston B,
and E and E' designate the slots or ports in the piston B¹ to admit the steam therein
to the ports e and e of the cylinder A, and the ports e¹ and e¹ of the cylinder A¹,
respectively. F and F designate the grooves or recesses in the piston B, and F¹ and Fi
designate the grooves or recesses in the piston B¹, to connect the ports e and e with
the exhaust port d, and the ports e¹ and e¹ with the exhaust port d', respectively.
e, e etc. designate the small auxiliary starting holes in the pistons, and e³, e³ etc.
designate the auxiliary ports connecting the ports e and e¹ with the ends of the
cylinders A and A¹, to provide suitable cushioning for the pistons, and facilitate their
reversal when the pistons are not coupled or connected up to a crank shaft..
It will be understood that when the pistons are coupled up or connected with a
crank shaft to form a motor engine, the auxiliary starting holes ², e² etc., and the
auxiliary ports e, e etc. may be dispensed with.
The action of our improved engine is as follows:-Supposing the pistons to be in
the position shown by Figure 2 of the accompanying drawing, the steam or other
fluid (which it will be understood is constantly admitted to the interior of both of the
hollow pistons by means of the holes c and c¹ and the slots b and 6) passes out of
the piston B through the rear slot or port E to the port el, and thence to the rear end
of the cylinder A', impelling the piston B' forward, the steam in the forward end of
the cylinder A' exhausting through the port e¹ at the forward end of the cylinder A',
and thence by means of the rear groove or recess F in the piston B, through the
exhaust port d, to the exhaust chamber D. In the position shown by Figure 2. the

page_text: piston B¹ has moved forward so far that the rear slot or port E of the piston B¹ has
just commenced to coincide with the port e of the cylinder A', thus admitting steam
to the front end of the cylinder A through the port e, the steam in the rear end, of the
cylinder A exhausting through the port e at the rear end of the cylinder, and thence
by means of the rear groove or recess F¹ in the piston B¹, through the exhaust port d'
to the exhaust chamber D. As the piston B₁ approaches the front end of the
cylinder A¹ the piston B is being impelled towards the rear end of the piston A,
so that by the time the piston B¹ reaches the end of its stroke, the piston B has moved
so far towards the rear end of the cylinder A as to open the front groove or recess F
and the front steam slot or port E to the exhaust port d and steam ports e¹ and e¹,
providing for the admission of steam in front of the piston B¹, and for the exhausting
of the steam in the rear thereof.
This cycle of operations continues so long as steam is admitted to the chamber C,
the one piston acting as a distributing valve to the cylinder containing the other
piston continuously throughout its stroke, and vice versa, so that neither piston is at a
state of rest whilst the engine is in motion.
It will be understood that the sizes of the various openings or ports may be varied
to give a greater or less "cut off" as found necessary or desirable.
It will be seen that both pistons are alike at either end, so that they may be reversed,
or interchanged, and also that they are fitted with expansion rings at each end.
We are aware that duplex engines and pumps have already been made in which
each piston acts as a distributing valve to the other cylinder, and therefore we do not
broadly claim such as our invention, but having now particularly described and
ascertained the nature of our said invention, and in what manner the same is to be
performed, we declare that what we claim is :-
1. In a steam or other fluid engine having duplex cylinders and pistons, the latter
acting as distributing valves to the former; the arrangement of the cylinders, pistons
and ports or openings, specifically as and for the purpose set forth.
2. In a steam engine having duplex cylinders and hollow pistons, the latter acting
as distributing valves to the former; the particular arrangement of openings or ports,
and grooves and recesses, for admitting and exhausting the steam to and from the
alternate cylinders, whereby a uniform reciprocating motion is imparted to the two
pistons, enabling them to be coupled to a crank shaft as set forth.
3. In a steam or other fluid engine having duplex cylinders and pistons, the latter
acting as distributing valves to the former; the combination with the hollow pistons,
of the slots or ports E, E and E, E¹, and the grooves or recesses F, F and F, F', to
provide for the induction and eduction of the steam, to and from the cylinders while
the pistons are in motion, as set forth.
4. In a steam engine having duplex cylinders, with one steam and one exhaust
chamber common to both cylinders, and having hollow pistons acting as distributing
valves; the auxiliary steam holes e³, e etc. to facilitate starting the pistons in any
position, as set forth.
5. In a steam engine having duplex cylinders and hollow pistons, the latter acting
as distributing valves to the former; the combination with the said pistons and
cylinders, of the auxiliary starting holes e², e² etc., and the cushioning ports e³, e³ etc. as
set forth.
11
1
T
1000
ROBT. ED. PHILLIPS, M.I.M.E.,
Royal Courts Chambers,
70, Chancery Lane, London, W.C.,
Agent for the Applicants.