IMPROVE- MENTS IN STEAM GENERATORS AND ENGINES, AND IN APPARATUS FOR FEEDING STEAM GENERATORS
Year: 1865

page_text: in the County of Middlesex, Gentleman, for the Invention of "IMPROVE-
MENTS IN STEAM GENERATORS AND ENGINES, AND IN APPARATUS FOR FEEDING
STEAM GENERATORS."-A communication from abroad by George Bailey
Brayton, of Boston, Suffolk County, in the State of Massachusetts,
United States of America.
Sealed the 12th September 1865, and dated the 3rd May 1865.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition, on the
3rd May 1865.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, Gentleman, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN STEAM GENERATORS AND ENGINES, AND IN APPARATUS FOR
FEEDING STEAM GENERATORS," a communication to me from abroad by George
Bailey Brayton, of Boston, Suffolk County, in the State of Massachusetts,
United States of America, to be as follows:--
This Invention relates, firstly, to improvements in steam generators, whereby
economy of fuel and in the cost of the generator is obtained, and the danger
from explosion is obviated; secondly, to an improved apparatus for feeding
steam generators; and, thirdly, to an improved valvular arrangement of

page_text: reciprocating steam engines, whereby a simple and easy mode of effecting the
cut off" is obtained without the necessity for interfering with or adjusting
any of the actual moving parts, provision being at the same time made for
the perfect balancing and rendering uniform the action of reciprocating steam
engines.
According to the first part of this Invention it is proposed to generate
steam in tubes having a constant supply of water, such tubes being sur-
rounded by other tubes in contact therewith capable of being highly heated,
so that complete combustion of the gases emanating from the fuel while in con-
tact therewith may be effected whilst the elevated temperature is transmitted to
the enclosed generating tubes. Above, and resting upon the generating tubes,
which are placed at a slight inclination above the furnace, are arranged side
by side a number of cast-iron plates, with small spaces or intervals left between
them for the passage of the gases and products of combustion to the chimney,
the object of such plates being to check or retard the passage of the gases,
and by being highly heated to serve as magazines of heat when the fire is being
stoked. This generator is kept constantly supplied with hot water by means
of a self-acting feeding apparatus, which constitutes the second head of the
Invention, and consists of a vessel containing the 'feed water at the lower part,
whilst its upper portion is filled with steam from the generator itself, a steam
pipe being led from the generator to the upper portion of the vessel for that
purpose, whilst another pipe leads from the water space in the vessel to the
generating tubes of the generator, and consequently an equilibrium pressure
is exerted upon the water which flows into the generating tubes as required.
A pipe is also fitted on to the top of the vessel for the purpose of supplying
steam for the working of an engine, or for any other purpose required. Below
the body of the vessel, above described, there is formed a separate chamber
into which the exhaust steam is directed, so that the water in the vessel may
be heated by steam above and below it. The supply of water to the gene-
rating tubes is controlled and its action regulated by combining by means of
a contracted tube the said generator with the vessel or feed water 'reser-
voir, the water in the generator and in the reservoir being under the same
pressure.
According to the third part of this Invention 'it is proposed to employ a
variable and self-adjusting "cut-off" in steam engines operated by the
governor 'for the purpose of equalizing and rendering uniform 'the action of
reciprocating steam engines. For this purpose the D or slide valve is pro
vided with auxiliary steam ports opening out at the ends of the slide and in
the face thereof, communicating alternately with the ordinary steam ports

page_text: in the cylinder, such auxiliary steam ports being opened and closed more or
less according to the amount of steam to be admitted by means of small slide
or "cut-off" valves of their own. These cut-off" valves are carried on a
balance lever which is pivoted to one side of the main slide, and is worked by
a lever on the inner end of a rocking spindle which enters through a stuffing
box in the side of the valve chest. The outer end of this spindle carries a
cam lever which in the case of oscillating engines is tilted by coming in
contact during the oscillation of the cylinder with one or other of two sliding
cams or stops; these stops are brought into the requisite position for coming
in contact with the cam lever by means of a wedge or double incline piece
which slides between them, and so causes them to separate more or less, a
spring bringing them together again when the wedge is withdrawn; this
wedge is raised and lowered by being connected with the arms of a centrifugal
governor. It will thus be seen that the action of the governor is to open and
close more or less according to the speed of the engine the two "cut-off"
valves which slide over the auxiliary ports in the ends of the main D or slide
valve of the engine, the amount of such "cut-off" being regulated by the
positions of the sliding cams or stop pieces. The main slide or D valve is
worked by means of a vibrating lever arm, having its centre of motion within
the valve chest; this arm works inside the central or exhaust chamber of the
slide valve, and is there connected by jointed links to the opposite ends of
such chamber. This arrangement affords a yielding connection between the
slide valve and the vibrating lever arm, and admits of the valve reciprocating
along the plane surface of and in contact with the valve face, although the
end of the arm itself describes an arc of a circle. The rocking spindle which
carries the vibrating arm, above referred to, passes through a stuffing box in
the side of the valve chest, and carries (in the case of an oscillating engine)
a lever arm on its outer extremity, the lower end of such lever arm resting in
a fixed socket, so that the movement of the cylinder on its trunnions will
impart the requisite motion to the rocking shaft for working the main slide
valve.
Although, for the sake of convenience, I have described the valve motion
as it would be worked when applied to an oscillating engine, it is obvious
that by very slight modifications which will be readily understood by the
practical engineer, the same motion may be applied to reciprocating engines
having fixed cylinders.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Henry Jolinson in the Great Seal Patent Office on the
3rd November 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent bearing date the Third day of May, in the year of our Lord One
thousand eight hundred and sixty-five, in the twenty-eighth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the
said John Henry Johnson, Her special license that I, the said John Henry
Johnson, my executors, administrators, and assigns, or such others as I,
the said John Henry Johnson, my executors, administrators, or assigns,
should at any time agree with, and no others, from time to time and at
all times thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN STEAM GENERATORS AND ENGINES, AND IN APPARATUS FOR
FEEDING STEAM GENERATORS," a communication to me from abroad by George
Bailey Brayton, of Boston, Suffolk County, in the State of Massachusetts,
United States of America, upon the condition (amongst others) that I, the
said John Henry Johnson, my executors or administrators, by an instrument
in writing under my hand and seal, should particularly describe and ascer-
tain the nature of the said Invention, and in what manner the same was
to be performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date of the
said Letters Patent.
NOW KNOW YE, that I, the said John Henry Johnson, 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, reference being had to the accompanying Drawings,
and to the letters and figures marked thereon (that is to say :-
The said Invention relates, firstly, to improvements in steam generators,
whereby economy of fuel and in the cost of the generator is obtained, and the
danger from explosion is obviated; secondly, to an improved apparatus for
feeding steam generators; and, thirdly, to an improved valvular arrangement
of reciprocating steam engines, whereby a simple and easy mode of effecting

page_text: the "cut-off" is obtained without the necessity for interfering with or adjusting
any of the actual moving parts, provision being at the same time made for the
perfect balancing and rendering uniform of the action of reciprocating steam
engines.
According to the first part of this Invention it is proposed to generate
steam in tubes having a constant supply of water, such tubes being surrounded
by other tubes in contact. therewith capable of being. highly heated, so that
complete combustion of the gases. emanating from the fuel while in contact
therewith may be effected whilst the elevated temperature is transmitted to
the enclosed generating tubes. Above,. and resting upon the generating, tubes,
which are placed at a.slight inclination above. the furnace, are arranged side
by side a number of. cast-iron plates with small spaces or intervals left between
them for the passage of the gases and products. of combustion to the chimney,
the object of such plates being to check or retard the passage of the gases, and
by being highly heated to serve as magazines of heat when the fire is being
stoked. This generator is kept constantly supplied with hot water by means
of a self-acting feeding apparatus, which constitutes the second head of the
Invention, and consists of a vessel containing the feed water at the lower part,
whilst its upper portion is filled with steam from the generator itself, a steam
pipe being led from the generator. to the upper portion of the vessel for that
purpose, whilst another pipe leads from the water space in the vessel to the
generating tubes of the generator,. and consequently an equilibrium pressure
is exerted upon the water which flows into the generating tubes, as required.
A pipe is also fitted on to the top of the vessel for the purpose of supplying
steam for the working, of an engine or for any other purpose required. Below
the body of the vessel, above described, there is formed a separate chamber
into which the exhaust steam is directed, so that the water in the vessel may
be heated by steam above and below it. The supply of water to the gene-
rating tubes is controlled and its action regulated by combining, by means of
a contracted tube, the said generator with the vessel or feed water reservoir,
the water in the generator and in the reservoir being under the same pressure.
According to the third part of this Invention it is proposed to employ a
variable and self-adjusting "cut-off" in steam engines operated by the
governor for the purpose of equalizing and rendering uniform the action of
reciprocating steam engines. For this purpose the D or slide valve is pro-
vided with auxiliary steam ports opening out at the ends of the slide, and in
the face thereof, and communicating alternately with the ordinary steam ports
in the cylinder, such auxiliary steam ports being opened and closed more or
less according to the amount of steam to be admitted by means of small slide

page_text: or "cut-off" valves of their own; these "cut-off" valves are carried on a
balance lever which is pivotted to one side of the main slide, and is worked by
a lever on the inner end of a rocking spindle which enters through a stuffing
box in the side of the valve chest; the outer end of this spindle carries a
cam lever, which in the case of oscillating engines is tilted by coming in
contact during the oscillation of the cylinder with one or other of two sliding
cams or stops; these stops are brought into the requisite position for coming in
contact with the cam lever by means of a wedge or double incline piece which
slides between them, and so causes them to separate more or less, a spring
bringing them together again when the wedge is withdrawn; this wedge is
raised and lowered by being connected with the arms of a centrifugal
governor. It will thus be seen that the action of the governor is to open and
close more or less according to the speed of the engine the two "cut-off"
valves which slide over the auxiliary ports in the ends of the main D or slide
valve of the engine, the amount of such "cut-off" being regulated by the
positions of the sliding cams or stop pieces.
The main slide or D valve is worked by means of a vibrating lever arm,
having its centre of motion within the valve chest; this arm works inside the
central or exhaust chamber of the slide valve, and is there connected by
jointed links to the opposite ends of such chamber. This arrangement affords
a yielding connection between the slide valve and the vibrating lever arm,
and admits of the valve reciprocating along the plane surface of and in
contact with the valve face, although the end of the arm itself describes an
are of a circle. The rocking spindle which carries the vibrating arm above
referred to passes through a stuffing box in the side of the valve chest, and
carries (in the case of an oscillating engine) a lever arm on its outer
extremity, the lower end of such lever arm resting in a fixed socket, so that
the movement of the cylinder on its trunnions will impart the requisite motion
to the rocking shaft for working the main slide valve.
Although for the sake of convenience I have described the valve motion as
it would be worked when applied to an oscillating engine, it is obvious that
by very slight modifications, which will be readily understood by the practical
engineer, the same motion may be applied to reciprocating engines having
fixed cylinders.
And in order that the said Invention may be fully understood I shall
now proceed more particularly to describe the same, and for that purpose
shall refer to the several Figures on the annexed Sheets of Drawings,
the same letters of reference indicating corresponding parts in all the
Figures.

page_text: Figure 1, on Sheet 1 of the Drawings, is a sectional elevation of the improved.
generator, and Figure 2 is a transverse vertical section. across the generating.
vessels taken along the line X, X, in Figure 1. 9 represents the fire-space ;.
h, the grate bars; d,. the water vessel or vessels for the generation of steam,
which are formed in this case of wrought-iron tubes or gas pipes put. together.
in the ordinary manner.. These vessels or pipes d are all connected at one.
end with a horizontal water vessel c", which receives the supply of water and.
distributes it to the several generating vessels.d; with these are connected at.
their other ends upright vessels or pipes d', which ascend. about two feet, and.
are then bent into the form shewn in the Drawing, forming a series of hori-
zontal tubes, the steam, being allowed to pass off therefrom at i'; e, e, are the
intercepting or transmitting media, shown more clearly in Figure-2, intervening
between the water vessels or tubes. d. and. the fire;, in this. instance they are
made to conform to the external shape of the water. vessels, and to come into.
contact with the same. They are about one-half inch. in. thickness, and are-
divided into two pieces lengthwise, so as to be readily removed and replaced;
they can be kept in place by small pieces of metal wedged in between them..
This medium is made of any suitable material. which will best endure the
action of the fire ;, cast iron. answers. the purpose well. The generator, as
described, may be enclosed in. brickwork or cast-iron plates lined with any
good non-conducting, material.
The object of the employment of the intercepting and transmitting medium e.
is to bring the water vessel into close contact with the fire in order to absorb
the heat as soon as it. is generated, without interfering with the perfect com-
bustion of the gases,. This medium, whilst intercepting and transmitting heat
to the water tubes, becomes heated to a high degree, thus permitting a proper
combustion of the gases in. contact with it; by this means a slow natural
combustion may be made use of, preventing thereby the escape of a large
amount of heat to. the chimney.
The action of this apparatus in the generation. of steam is as follows:-
Water is supplied to the generating vessels d by any suitable means whereby
they may receive a sufficient and regular supply, and is allowed to rise in the
upright vessels d¹ to any given height. Heat from the fire g acts first upon
the vessels through the media e, as above explained, and then passes up and
amongst the horizontal pipes d" on its way to the chimney k. Steam when
generated in the vessels d passes up and into the series of horizontal pipes in
which any water which may be carried up by the rapid rush of steam along
the upright pipes is also converted into steam.
In the form of generator which I have described, consisting of a series of

page_text: pipes placed in the flame of the fire I have given them a sufficient inclination
upwards from the point where they receive the supply of water to the point
where they join the upright pipes to cause or allow steam to flow in that
direction. Plates m, m, made of cast iron are placed above and near the
upper surface of the media e, leaving sufficient space for the flames to pass
between them and the several media. Each plate extends from the centre of
one vessel to the centre of the next, allowing but a small space between the
different plates. The object of these plates is to retard the escape of the
flames, and to cause them to follow a course in conformity with the shape of
the upper surface of the water vessel, thus keeping the flames in contact with
their whole surface, and permitting a large proportion of the heat to be taken
up by the vessels before the gases finally pass up between the plates. The
plates becoming highly heated act as heat reservoirs or magazines, and during
the operation of stoking or replenishing the fire, they give out heat to the
generating vessels, thus serving to equalize or make up for any sudden
decrease in the intensity of the fire; they can be made of cast iron or other
suitable material.
The feed apparatus, which constitutes the second part of this Invention, is
also illustrated in elevation in Figure 1; it consists of a closed metallic
vessel a wholly removed from the direct action of the fire. It has but one
water and one steam communication with a steam generator, the latter at or
near its top to allow steam from the generator to flow in upon the upper
surface of the water it contains in order to maintain the same pressure in
both, and the former at or near the bottom for water to flow to the generator;
it can thus receive heat only from steam acting upon the upper surface of
the water it contains. This supplemental vessel is designed for and appli-
cable to a steam generator capable of containing only a very small quantity of
water as compared with the ordinary forms of steam boilers of the same steam-
generating capacity..
The operation of this apparatus, which the Inventor calls a "safety sup-
plemental steam and water vessel," in connection with a steam-generating
apparatus, is as follows:-Water is admitted to the vessel a to any deter-
mined height by pressure from the pump, or other equivalent means, through
the pipe, whence it flows into and finds its level in the generator by the
pipe c, the bottom of which is placed below the water line of the vessel. The
height to which water is to be admitted to the vessel a may be determined by
any suitable means for determining the height of water to be maintained
in a steam boiler; a common copper float in the vessel connected with and
operating a throttle valve in a cold-water pipe leading to a force pump kept

page_text: in constant operation will answer. When steam is formed in the generator
it passes into the vessel a through the pipe i above the surface of the water
it contains, and water continues to flow to the generator through the pipe c
as fast as water is there converted into steam, thus maintaining the same
level in both; steam may be drawn from the vessel a through the pipen to
supply an engine, or for other
purposes.
The object of this vessel a in connection with a steam-generating apparatus
of small water capacity may be explained as follows:-It is considered
necessary in order to operate with safety the ordinary forms of steam boilers,
to keep a large body of water in the boiler itself, and the greater the quantity
of water which can be properly held in an ordinary boiler the greater the
degree of safety with which it can be operated, because any sudden lack of
water is less liable to take place, and much time is thus given to discover any
gradual diminution in the quantity of water; but in such cases the water in
the boiler becomes heated to a high temperature, and if such a boiler with
steam at one hundred pounds pressure to the square inch were opened to the
atmosphere by accident or otherwise, enough steam would be given out from
the water to equal in volume about eight hundred times the quantity of water
contained, which would cause damage in exerting its expansive force. Now this
vessel a contains in direct communication with the steam and water of a steam
generator a body of water which, whilst it is wholly removed from the direct
action of the fire, still maintains to the generator, as far as relates to a
sufficient supply of water, the same relation that it would if held in the
generator itself, with only this difference, that it is kept at an average tem-
perature below its boiling point, thus ensuring safety, for if this vessel a were
open to the atmosphere, by accident or otherwise, with a pressure of steam at
one hundred pounds to the square inch, little steam would be given out by
the water it contains to cause damage by its expansive force, and as in such
a case little steam can come from a generator, such as it is designed to use
with this vessel, owing to the fact of its containing but a very limited body of
water from which steam could be developed, as before explained, the wholo
apparatus is rendered safe. An advantage is also secured by the use of this
vessel in combination with the form of generator mentioned, as only a small
radiating surface is obtained confined entirely to the vessel a, which not being
exposed to the direct action of the fire can be effectually and permanently
protected by any good non-conducting material. The vessel a can also be
made of cast iron, thus reducing the cost over that of wrought iron. A closed
vessel or chamber 6 is connected with the bottom of the vessel a, and acts
as a receiver of exhaust steam from an engine.

page_text: In the apparatus represented in the Drawing I have extended the sides of
the vessel a down to the bottom of a vessel (6), thus making the sides of
the two vessels in one piece. Exhaust steam from an engine is admitted to
the vessel (6) through the pipe o, and comes in contact with the under
surface of the vessel (a), and transmits beat to the water on the upper sur-
face, thus heating the water before it passes to a generator by the pipe c..
The pipe (c) is placed at some distance from the bottom of the vessel (a) to
allow the water admitted through the pipe (2), to become properly heated.
before passing off to the generator. An outlet for the steam to escape from
the vessel (6) is provided by the pipe (p). which opens to. the atmosphere..
By this combination of a feed water heater with a steam and water vessel in
a steam-generating apparatus considerable economy. both as to cost. and space
to be occupied is obtained. The pipe (c) is contracted at (c),.the contraction.
being of a capacity to be determined by testing the evaporating power of the
generator when filled with water to the proper height; the size of the opening
is then gauged or reduced so as to admit but little more water in a given time
than can be evaporated in that time by the generator under the conditions of
its regular action; thus, in case water should wholly leave the generator, from
whatever cause, this supply of water when again admitted would soon be
sufficient to meet all demands upon the generator for steam, and gradually fill.
it to the required height. The object of this device, or the result to be
obtained from its use, can be explained as follows:-If by any means the
generator during its operation should become highly heated from the absence
of water, and if then it should again commence to fill up, or the interrupted
supply commence to flow in, the supply of water to and the action of the same-
in the generator is so regulated or limited that no explosion can take place,
for from this supply of water sufficient steam is evaporated to gradually raise
the pressure to the required point, while the overheated generator is reduced
to its proper temperature, and is filled up to the usual height, when. the
regular action again commences. Were a large body of water, or a quantity
much exceeding the evaporating capacity of the generator under the con-
ditions of its regular action to be at once admitted into the highly heated
generator, an excessive quantity of steam would be instantly given off to
explode the generator, which would be much weakened while thus over-
heated.
It will be seen from the foregoing explanation of the nature and mode of
operation of this part of the said Invention, that I am enabled by simple and
efficient means to control the supply of water to, and regulate the action of
the same in a steam generator of a prescribed nature, so that while its regular

page_text: action is such as to permit a body of water to be held in the generator, it
wholly avoids the danger of exploding the same if by any means it should
become highly heated from the absence of water and the interrupted supply
again be allowed or commence to flow in, and it also causes or permits a
gradual filling up of the generator to the proper height, and a return to its
regular condition and action.
It is well known that many attempts have been made to operate steam
generators in a manner to render explosion impossible by supplying at regular
intervals a specified amount of water by pressure from a pump or other
equivalent means, which falling upon the highly heated surface of a generator,
is instantly converted into steam. In such cases the amount of water thus
admitted is limited to the requirements or demands made upon the generator
for supplying an engine at each stroke of its piston, and the proper action of
the engine is dependent upon providing the proper quantity of water.
Such attempts as the above have been found to be attended with great un-
certainty of action, if not wholly impractical, from the great difficulty of
properly regulating the supply of water to meet the varying demands of the
engine, or to give the engine a uniform and equal motion.
Another difficulty exists from the fact that a generator heated to a high
temperature is always subjected to the destroying action of the fire. Tho
above-mentioned difficulties are overcome by this Invention, as explained, and
at the same time explosions are rendered impossible.
The third part of this Invention, which relates to the valvular arrangement
of all kinds of reciprocating steam engines, is designed to secure a simple and
easy inode of adjusting the cut-off of the steam without it being necessary to
interfere with or adjust any of the actual moving parts. Provision is at the
same time made for the perfect balancing and rendering uniform the action of
reciprocating steam engines.
On Sheet 2 of the accompanying Drawings I have shewn an oscillating
steam engine constructed, arranged, and operating in accordance with this
part of the said Invention.
Figure 3 (Sheet 2) is an elevation, partly in section, of the improved steam
engine complete, the plane of section passing through the axis of the governor,
and being parallel with the longitudinal axis of the cylinder.
Figure 4 is an end view, partly in section, of the same, the plane of section
passing through the line a, b, in Figure 3, or transversely to the longitudinal
axis of the cylinder, and Figure 5 is a vertical section taken along the
line c, d, in Figure 4 through the cylinder and steam chest, showing the
method of working the main and auxiliary valves.

page_text: Upon a frame A, in suitable bearings B, is hung the steam cylinder C,. to
which an oscillating motion is imparted by the piston rod E working directly
on a crank F. The cylinder is provided with steam ports G and G¹, and a
central exhaust port H, and is surmounted by a steam chest D containing the
slide or D valve I, to which the slide movement on the valve face is given by
means of a vibrating lever J mounted upon a rocking shaft K, which tra-
verses a stuffing box in the back of the steam chest. On the outer end of
the rock shaft K is keyed or otherwise secured at its upper end a lever L,.
whilst its lower end is engaged in a socket M fast to the frame so as to be
stationary. The cylinder in its oscillation carrying with it the shaft K, whose
outside lever is engaged in the stationary socket M, it will be understood
that it will impart a rocking motion to the said shaft which is transmitted to
the lever J. With this lever J are combined two short toggle levers N,
which are pivoted in the recess of the main slide valve affording a yielding
connection, so that whilst the lever J describes an arc of a circle the valve
will be moved along the plane surface of and in contact with the valve seat.
The slide valve is kept in place, and truly guided in its course, by means of a
guide bar O projecting from the chest cover, fitting a groove in the top of the
main valve (Figure 4.) The main slide valve is provided with auxiliary
ports P, P¹, through which steam from the chest is admitted into the cylinder;
these auxiliary steam ports in the main slide valve are curved so as to ter-
minate respectively in the ends and under side of the slide valve. Against
the ends of the main slide valve play the auxiliary slide valves Q and Q',
which are mounted on a balance lever R pivoted to or hung in the rear of the
main or D valve. This balance lever receives an oscillating movement in
the following manner-Upon a suitable bracket or standard S is a mounted
governor T of centrifugal action, i.e., a governor consisting of two or more
balls, which are jointed to a revolving shaft driven directly by the engine, so
that according to the speed of revolution imparted to the shaft the balls
diverge from or converge towards the axis of revolution. The balls are also
connected with a central rod which is raised or lowered in its sleeve according
to the position of the balls, and consequently according to the speed of the
engine which is dependent upon the supply of steam. If the speed of rotation
exceed that calculated for safety the supply of steam is to be diminished; this
is effected in ordinary steam engines by combining the governor with a
throttle valve in the main steam supply pipe; in this case, however, steam is
cut off at each stroke of the piston, so that the quantity of steam admitted
will be such as to ensure uniform action of the engine. This cutting-off is
effected by the auxiliary slide valves Q and Q'; to this effect the central rod

page_text: or spindle is provided at its lower end with a double wedge W, which as it
moves up and down with the said central rod causes a double or divided
cam W¹ held together by a spring to diverge or converge according to the
position of the wedge W; this cam is centrally placed in relation to the
spindle, i.e., in line with the axis of the governor which passes through
the centre of the trunnions. Through the steam chest on the side of the
governor passes another shaft Y, having on the end outside the chest a cam
lever X, which is tilted by coming in contact with the cam W₁ placed in its
path when the engine is oscillated. This movement is participated in by a
lever Z on the other end of the shaft Y in the interior of the valve chest,
which lever is provided with lugs which are arranged immediately underneath
the balance lever R, whereby the movement the cam lever receives in its
double oscillation, i. e., the oscillation of the cylinder and the oscillation on
its own point of suspension is directly transmitted to the balance lever which
operates the variable cut-off or auxiliary slide valves. By this arrangement,
or mode of connecting the rocking cam lever with the balance lever, the main
slide valve is permitted to reciprocate without interfering with the operation
of the auxiliary slide valves.
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried
into effect, I would observe, in conclusion, that what I consider to be novel
and original, and therefore claim as the Invention secured to me by the herein-
before in part recited Letters Patent is,―
First, the surrounding of the steam-generating tubes in apparatus in which
steam is generated in tubes having a constant supply of water with other
tubes in contact with the steam-generating tubes, and capable of being
highly heated, substantially in the manner and for the purpose herein-before
described.
Second, the application and use to and in the furnace of a steam-generating
apparatus of the plates m, substantially as and for the purpose herein-before
described.
Third, the employment of the vessel a operating as a steam drum and feed-
water reservoir in combination with a steam generator, substantially as herein-
before described and illustrated by the Drawings.
Fourth, in combination with the above I claim forming an exhaust steam
chamber under the body of the feed water, so that it shall be heated both from
above and from below, substantially as set forth.
Fifth, in a tubular steam-generator, substantially as described, I claim
controlling the supply of water and regulating its action by combining by

page_text: means of a contracted tube the said generator with a reservoir, the water in
both being under the same pressure, substantially as described.
Sixth, the combination with a tubular steam generator of the description
above referred to with a water reservoir under the arrangement described,
so that the water shall be maintained in the reservoir at a temperature less
than two hundred and twelve degrees Fahrenheit, and shall enter the generator
by tending to balance the hydrostatic pressure between the generator and the
reservoir, substantially as herein set forth.
Seventh, the variable and self-adjusting cut-off operated by the governor
for equalizing and rendering uniform the action of steam engines, as herein-
before described.
Eighth, the combination with the ordinary slide or D valve of auxiliary
steam ports and slide valves, arranged and operating substantially as herein-
before set forth.
Ninth, the method of operating the main slide or D valve by means of a
vibrating lever or arm having its centre of motion within the chest, as berein-
before described.
Tenth, the method of connecting the oscillating arm with the slide or D
valve, affording yielding connection so as to admit of the valve reciprocating
along the plane surface of and in contact with the valve face, as herein-
before described.
Eleventh, the method of operating the auxiliary valves hung upon the
end of an inert balance beam or lever by means of a rocking lever so arranged
as to admit of traverse motion of the balance beam or lever, together with
the main valve, substantially as herein-before described and illustrated by the
Drawings.
Twelfth, the method of regulating the action of the auxiliary or cut-off
valves by means of a cam which is expansible by the action of the governor,
substantially as herein-before described.
In witness whereof, I, the said John Henry Johnson, have to
this my Specification set my hand and seal, the Third day of
November, in the year of our Lord One thousand eight hundred and
sixty-five