IMPROVEMENTS IN APPARATUS FOR OBTAINING MOTIVE POWER, WHICH APPARATUS IS ALSO APPLICABLE TO THE CONDENSATION AND RAREFACTION OF GASES AND VAPOURS
Year: 1876

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields, in the
County of Middlesex, Gentleman, for the Invention of "IMPROVEMENTS IN
APPARATUS FOR OBTAINING MOTIVE POWER, WHICH APPARATUS IS ALSO
APPLICABLE TO THE CONDENSATION AND RAREFACTION OF GASES AND
VAPOURS." communication from abroad by Jehosaphat Davy Postle, of
Sydney, in the Colony of New South Wales, Engineer.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at
the Office of the Commissioners of Patents on the 29th September 1876.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN APPARATUS FOR OBTAINING MOTIVE POWER,
WHICH APPARATUS IS ALSO APPLICABLE TO THE CONDENSATION AND RAREFACTION
OF GASES AND VAPOURS." A communication from abroad by Jehosaphat Davy
Postle, of Sydney, in the Colony of New South Wales, Engineer.
This Invention relates to apparatus for converting heat into motive power, and
consists of a mechanical arrangement in which the motive power force may be
generated in the two following modes, namely
:-
First. Partly by the alternate generation and condensation of steam, and partly
by the alternate rarefaction and condensation of air or of other gases at any density,
such rarefaction and condensation being due to variations of temperature in the air
or other gases.
2nd. By the alternate rarefaction and condensation of air or of other gases at
any density without steam, such rarefaction and condensation of the air or of other
gases being due to variations of temperature in the air or other gases.
The apparatus can also be used for the compression and rarefaction of gases and
vapours, the compression and rarefaction of the gases and vapours being effected by
alternate rarefactions and condensations of portions of the gases and vapours them-
selves through the agency of changes of temperature.
In the first method of producing the motive-power force the maximum pressure
in the apparatus is produced when the steam is generated in it and the air in it is
heated and the minimum pressure is produced when the steam is condensed and the
air is cooled. In the first instance the steam is generated and the air heated by
causing the air charged with water in a finely divided state mechanically suspended

page_text: in it to pass over and in contact with metallic surfaces heated by the fuel or other
heating medium used in the apparatus. The minimum pressure in the apparatus is
produced by causing the steam and hot air to pass over metallic surfaces of sufficient
area to condense the steam and cool the air, and subsequently to meet jets and sprays
of water which have the effect of further cooling the air and again charging it with
water mechanically suspended in it. The metallic surfaces on which the steam is
condensed and the air cooled store up the latent heat of the steam, a portion of the
sensible heat of the water resulting from the condensation of the steam and a portion
of the sensible heat of the air.
When the steam is generated the second time, the air carrying the water in the
manner described, passes over the metallic surfaces last referred to and which may
be termed a regenerator. In passing over the regenerator surfaces the water carried
by the air absorbs the heat from the regenerator and is converted into steam, and
the air is heated. The steam is superheated and the air is further heated by being
caused to pass over those surfaces referred to heated by the fuel or other heating
medium used in the apparatus.
This method last described of producing the maximum pressure in the apparatus
and the method also described of producing the minimum pressure in it are
alternately repeated whilst the apparatus is at work.
The mechanical apparatus for carrying the above into effect consists principally of
a cylindrical vessel provided with a displacer, formed somewhat similarly to a
_ piston, working freely in it. When this displacer is moved to that end of the vessel.
in which the water is injected the gaseous contents are shifted to the hot-end,-in-their-
passage passing over the regenerator surfaces. When the displacer is moved to the
hot end of the vessel the gaseous contents are shifted to the cold end of the vessel,
in their passage passing back again over the regenerator surfaces. Connected with
this vessel is another smaller cylinder fitted with a piston and rod to which is
attached a connecting rod transmitting motion to a crank shaft.
The motions of the displacer and the piston of the smaller cylinder referred to are
synchronous whilst the displacer is moving, but the piston of the smaller cylinder
has a longer stroke than the displacer, and continues to move when the displacer is
at rest. On the return stroke the relative motions or the displacer and the piston
are the same. At the termination of each stroke a valve opens, when any excess of
pressure in the vessel over that of the external atmosphere is destroyed by the
escape of a portion of the air acted on, or if the pressure in the vessel is less than
the external atmosphere fresh air is admitted. By connecting this valve opening
with a closed receiver air or other gases at any density may be used by charging
the whole apparatus with air or other gases at the required pressure, which may be
maintained in the case of leakage by means of a small pump.
The position of the vessel is vertical, and the heat by preference is applied to the
upper end whilst the injection of water occurs at the lower end. The injection of
the water into the vessel and the ejection of water from it occur through the
variations of pressure in the vessel. The ejection of water occurs when the pressure
in the vessel is greater than the external pressure, and the injection takes place
when the external pressure is greater than the internal pressure. The same water 4
in the apparatus may be used over and over again by partly filling the receiver
.before mentioned with water. The injection water is drawn from the receiver, and
the ejection water is discharged into it. This water in the receiver can be kept
cool by causing cooling water to circulate through a coil immersed in it.
4
In the second method the motive power is produced by the expansion and con- 5
traction of comparatively dry gases, such for example as the atmosphere. In this
case the injection water may be dispensed with, and the injection end of the vessel
in which the displacer works be kept cool by cold water caused to circulate through
a jacketed space. The mechanical arrangements of the apparatus in all other
respects are similar to those already described.
When the apparatus is intended to effect the compression and rarefaction of gases
and vapours in separate vessels the valve opening is not connected with the receiver
5

page_text: before mentioned but is connected with two vessels, one of which contains the gas
to be rarefied, the other being the vessel into which the gas is to be compressed.
The former vessel is provided with a valve opening outwards, whilst the latter
vessel is fitted with a valve opening inwards. Upon the apparatus being set to
work the gaseous contents of one vessel will be partly withdrawn and compressed
into the other vessel.
The injection water may or may not be used according to the nature of the gas or
vapor being rarefied. When the injection water is not used the lower end of the
vessel first mentioned should be jacketed in the manner and for the purpose already
described.
Prior to the apparatus being set in motion for the compression of air or of other
gases the stroke of the piston of the small cylinder should be adjusted to equal the
stroke of the displacer. This is effected by altering the position of the crank pin in
the crank disc. When the apparatus is adjusted in this manner the greatest and
least pressures will occur at the terminations of opposite strokes, that is to say the
greatest pressure will occur when the displacer is at the cool end of the vessel, and
the least pressure when the displacer is at the hot end of the vessel.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Henry Johnson in the Great Seal Patent Office on the 28th
March 1877.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN APPARATUS FOR OBTAINING MOTIVE POWER,
WHICH APPARATUS IS ALSO APPLICABLE TO THE CONDENSATION AND RAREFACTION
OF GASES AND VAPOURS." A communication from abroad by Jehosaphat Davy
Postle, of Sydney, in the Colony of New South Wales, Engineer.
The said Invention relates to apparatus for converting heat into motive power,
and consists of a mechanical arrangement in which the motive power force may be
generated in the two following modes, videlicet:
1. Partly by the alternate generation and condensation of steam, and partly by
the alternate rarefaction and condensation of air or of other gases at any density,
such rarefaction and condensation being due to variations of temperature in the air
or other gases.
2. By the alternate rarefaction and condensation of air or of other gases at any
density without steam, such rarefaction and condensation of the air or of other gases
being due to variations of temperature in the air or other gases.
The apparatus can also be used for the compression and rarefaction of gases and
vapours, the same being effected by the alternate rarefaction and condensations of
portions of the gases and vapours themselves through the agency of changes of
temperature.
According to the first mode of producing the motive power force the maximum
pressure in the apparatus is produced when the steam is generated in it, and the air
in it is heated and the minimum pressure is produced when the steam is condensed
and the air is cooled. In the first instance the steam is generated, and the air
heated by causing the air charged with water in a finely divided state mechanically
suspended in it to pass over and in contact with metallic surfaces heated by the fuel
or other heating inedia used in the apparatus. The minimum pressure in the
apparatus is produced by causing the steam and hot air to pass over metallic
surfaces of sufficient area to condense the steam and cool the air, and subsequently
to meet jets and sprays of water which have the effect of further cooling the air and
again charging it with water mechanically suspended in it. The metallic surfaces
on which the steam is condensed and the air cooled store up the latent heat of the
steam, a portion of the sensible heat of the water resulting from the condensation of
the steam, and a portion of the sensible heat of the air.

page_text: When the steam is generated the second time the air carrying the water in the
manner described passes over the metallic surfaces last referred to, and which may
be termed a regenerator. In passing over the regenerator surfaces the water carried
by the air absorbs the heat from the regenerator and is converted into steam, and
the air is heated. The steam is superheated and the air is further heated by being
caused to pass over those surfaces referred to heated by the fuel used in the apparatus.
This method last described of producing the maximum pressure in the apparatus
and the method also described of producing the minimum pressure in it are alter-
nately repeated whilst the apparatus is at work.
The mechanical apparatus for carrying the above into effect consists principally
of a cylindrical vessel provided with a displacer formed somewhat similarly to a
piston working freely in it. When this displacer is moved to that end of the vessel
in which the water is injected the gaseous contents are shifted to the hot end in
their passage passing over the regenerator surfaces. When the displacer is inoved to the
hot end of the vessel the gaseous contents are shifted to the cold end of the vessel,
in their passage passing back again over the regenerator surfaces. Connected with
this vessel is another smaller cylinder fitted with a piston and rod, to which is
attached a connecting rod transmitting motion to a crank shaft.
The motions of the displacer and the piston of the smaller cylinder referred to are
synchronous whilst the displacer is moving, but the piston of the smaller cylinder
has a longer stroke than the displacer, and continues to move when the displacer is
at rest. On the return stroke the relative motions of the displacer and the piston
are the same. At the termination of each stroke a valve opens, when any excess of
pressure in the vessel over that of the external atmosphere is destroyed by the
escape of a portion of the air acted on, or if the pressure in the vessel is less than
the external atmosphere fresh air is admitted. By connecting this valve opening
with a closed receiver air or other gases at any density may be used by charging
the whole apparatus with air or other gases at the required pressure which may be
maintained in the case of leakage by means of a small pump.
The position of the vessel is vertical, and the heat by preference is applied to the
upper end whilst the injection of water takes place at the lower end. The injection
of the water into the vessel and the ejection of water from it occur through the
variations of pressure in the vessel. The ejection of water occurs when the pressure
in the vessel is greater than the external pressure, and the injection takes place
when the external pressure is greater than the internal pressure. The same water
in the apparatus may be continually re-utilized by partly filling the receiver before
mentioned with water. The injection water is drawn from the receiver, and the
ejection water is discharged into it. This water in the receiver can be kept cool by
causing cooling water to circulate through a coil immersed in it.
According to the second modification the motive power is produced by the
expansion and contraction of comparatively dry gases, such for example as the
atmosphere. In this case the injection water may be dispensed with, and the
injection end of the vessel in which the displacer works be kept cool by cold water
caused to circulate through a jacketed space. The mechanical arrangements of the
apparatus in all other respects are similar to those already described.
When the apparatus is intended to effect the compression and rarefaction of gases
and vapours in separate vessels the valve opening is not connected with the receiver
before mentioned, but is connected with two vessels, one of which contains the gas
(for example) to be rarefied, the other being the vessel into which the gas is to be
compressed. The former vessel is provided with a valve opening outwards, whilst
the latter vessel is fitted with a valve opening inwards. Upon the apparatus being
set to work the gaseous contents of one vessel will be partly withdrawn and com-
pressed into the other vessel.
The injection water may or may not be used according to the nature of the gas
or vapour being rarefied. When the injection water is not used the lower end of
the vessel first herein-before mentioned should be jacketed in the manner and for
the purpose already described.

page_text: Prior to the apparatus being set in motion for the compression of air or of other
gases the stroke of the piston of the small cylinder should be adjusted to equal the
stroke of the displacer; this is effected by altering the position of the crank pin.in
the crank disc. When the apparatus is adjusted in this manner the greatest and
least pressures will occur at the terminations of opposite strokes, that is to say, the
greatest pressure will occur when the displacer is at the cool end of the vessel, and
the least pressure when the displacer is at the hot end of the vessel.
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 two Sheets of Drawings, the saine letters of
reference indicating corresponding parts in all the Figures.
Figure 1 (Sheet 1) of the accompanying Drawings represents a vertical section of
an engine constructed according to the said Invention; Figure 2 (Sheet 2) is an end
elevation of the same.
Figure 3 (Sheet 1) is a sectional view illustrating a modification.
A is the furnace, the arrows indicating the draft and the direction taken by the
gaseous products of combustion downwards along the course of the flue. B is the
vessel for receiving the air and water acted on; it consists principally of two
metallic cylinders, one placed on the other. C is the displacer; it moves freely in
the cylinder L, which is bored out to receive it; it is attached to the rod D, working
inside the piston rod E and the stuffing box F. The rod D has also tappets G¹, G,
attached to it, and works in the guide H. The piston rod E is attached to the
piston I. Upon the down stroke of the piston rod the rod D with the displacer C
attached is carried down with it, owing to the friction of the packing in the stuffing
box F. When the tappet G¹ comes in contact with the guide H, the motion of the
displacer C and the rod D is arrested, the piston rod E with its piston I however con-
tinuing its motion to the end of the stroke. The packing of the stuffing box F may
consist of one or more steel rings together with the usual stuffing box and gland.
The steel rings exert a continuous pressure on the rod D, giving the necessary
friction to cause the rod D to move with the rod E until the former is stopped by
the tappets G¹, G, which strike the guide H at each stroke. The piston I works in
the cylinder J, the end of which situate in the vessel B is open. K is the cover of
the cylinder J, and which is provided with a stuffing box and gland through which
the rod E works. M is a port or passage leading from the interior of the vessel B
to a slide valve N, which admits of the ingress and egress of air or vapour, such
valve opening at the termination of each stroke. O is a pipe connecting the valve
chest P with a receiver Q for holding the injection water, and also for holding air
at any density. The injection water occupies about one-third of the space of the
receiver, and is maintained cool by a coil R, through which cold water is passed.
S is a pump with a self-acting arrangement for regulating the pressure of the air in
the receiver Q. The pump Š is fitted with an ordinary plunger a working in the
cylinder 6¹.
For regulating the compression of the air a cylinder is provided fitted with a
plunger c, which is loaded by the pressure of the lever attached at one end to a
spring. The plunger is hollow, the air being allowed free access to the interior
through the holes d, d. Assuming the pressure in the receiver Q to be not more
than that of the atmosphere, the plunger e will occupy the position shown in the
Drawing. If it is desired to pump and maintain a pressure of air in Q of, say
20 lbs. on the square inch, the plunger c is loaded to that pressure, and upon the
plunger a being set in motion, air through the opening e will be drawn in and dis-
charged at the end of the stroke of the plunger a, there being an outlet valve for
this purpose; this will proceed until the pressure per square inch in Q equals the
pressure per square inch on the plunger c. Upon more air being pumped in, the
plunger c will move upwards, closing the inlet e and opening the aperture f; as this
aperture is below the plunger a, air will be drawn in at the up stroke, but it will
also be discharged at the down stroke through the same opening without being com-
pressed, consequently no power is wasted when air is not being pumped into Q

page_text: except that necessary to overcome the friction of the plunger. If through any
leakage occuring the pressure in Q should become less, the plunger will descend
and open e and close f; compression will then take place, and air will be forced
into Q. The plunger c is prevented from moving higher than a certain point by
the pin g.
T is the water supply pipe. When the pressure in the cylinder B is less than the
pressure in the receiver Q, the water is forced up and out through small openings
in the pipe in the form of fine spray, saturating the air with moisture, and causing
small particles of water to be suspended in it. The pipe T is provided with a stop-
cock U for regulating the supply of water, and with a check valve V opening
inwards for preventing the backward flow of water when the pressure in B exceeds
the pressure in Q. W is a pipe provided with a stop valve WI; it affords when the
valve is open a free communication between the vessel B and the vessel Q. When
the engine is working this valve is closed. In order to stop the engine the valve
should be opened; when it is open the pressure in the receiver Q and the vessel B
is the same, consequently there can be no motion. X is a pipe forming a commu-
nication between the receiver Q and the vessel B; it is fitted with a valve Z, which
is acted on by the lever h, h, of the governor Y. At a high velocity the valve Z is
opened, when the same results are obtained which occur on opening the stop valve
Won the pipe W. When the velocity diminishes the valve closes. The valve
can be-set to open at any velocity.
Motion is imparted to the governor Y through the intervention of the bevel
gearing from the crank shaft l. Z, Z, is the regenerator, which is formed of
thin concentric cylinders of sheet metal; i is a pulley for transmitting the power
of the engine by belting; J¹ is the fly wheel; k, k, are plummer blocks for carrying
the crank shaft ; m is the crank disc; it has holes bored in it to receive the crank
pin m¹ in two different. positions, to which pin is attached one extremity of the
bifurcated connecting rod H¹; h is the excentric for working the pump; n¹ is the
excentric for working the slide valve; o is the standard for supporting the lever of
the governor; p is a pipe forming a constant open communication between the ;
under side of the piston I and the receiver Q, the port p¹ in the cylinder J being
connected with the pipe p; is an opening through which oil is injected for lubri-
cating the piston I. The oil forms a layer of a depth of, say one inch, and the
bottom of the piston, which is cup formed, dips in it at each downward stroke, and
carries upwards the oil, lubricating the sides of the cylinder J, which are always :
kept cool by the cold water injected; r, 7, is the space under the displacer C when it
at the end of the upward stroke; 8, 8, are openings in the cylinder L to admit the
passage of air to and fro; t is a pipe connecting the vessel B with the receiver Q.
This pipe is fitted with a stop cock U¹, and with a retention valve V, opening
downwards; it is provided for the purpose of conducting the excess of water in the
bottom of the chamber B to the receiver Q. The water is forced down the pipe
when the pressure in B is greater than in Q; but when the pressure in Q is greater
than in B, the water is prevented from passing upwards by the retention valve V¹.
The cock should be adjusted so that a small quantity of water is always retained in
the bottom of the vessel B; the engine operates in the following manner:-The
receiver Q being about one-third filled with water, and the fire in A having been
lighted, and the stop valve W₁ on the pipe W closed, the piston I, if at about half
stroke, will commence to move downwards, being caused to do so by the pressure
resulting from the air being heated in the space between the top of the cylinder L
and the displacer C; at the end of the stroke the valve N opens, and any excess of
pressure in the vessel B over that in the receiver Q is destroyed by the air escaping
through the pipe O into the vessel Q. At the commencement of the up stroke the
valve N closes, and the piston, together with the displacer C, moves upwards; the
hot air in the space above the displacer C is forced through the opening b. The
piston I, however, carrying with it the piston rod E, continues to move upwards to
the completion of the stroke when the valve N opens; and if the air in the vessel
B is of less pressure than in Q air from Q rushes through the valve opening and

page_text: mingles with the air already charged with the moisture in the manner described
under the displacer C. Upon the commencement of the down stroke the air and
water pass through the space a over the regenerator plates, when the air is heated
and the water is converted into steam by contact with them; both are further
heated by passing through the annular space before mentioned, whence pressure
results, and the piston moves downwards. When the tappet, G₁, comes in contact
with the guide H its motion is arrested; the bottom of the displacer C will now be
close to the cover of the cylinder L.
The piston, as before described, moves outwards to the end of the stroke, being
impelled thereto by the pressure generated by the steam and air; at the termination
of the stroke any excess of pressure is destroyed in the manner herein-before
described. This reciprocating motion is continued, and the same water is used over
and over again; it is cooled, however, by being brought in contact with the surface
of the coil R. Should any loss of water occur the supply may be restored to its
original quantity by means of a pump worked from the crank shaft. For the pur-
pose of starting a large engine, a lever capable of being connected or disconnected
at will with the rod D may be fitted to it. By the aid of this lever, when the
engine is worked with the tappet motion, the displacer C may, at certain parts of
the stroke, be moved up and down without the piston rod E being moved. As
the displacer is thus moved, it will, at the pleasure of the mover, cause an increase
or decrease of the pressure on the piston I; the engine is also worked without the
tappet motion by a slight adjustment of the crank pin, in which case the stroke of
the displacer C will be the same as the piston. If the stroke of the former is, say
five inches, and the stroke of the piston I fifteen inches, the crank must be fitted
into a suituable hole in the crank disc two and a half inches from the centre of
the disc. As this hole is bored out ready for this adjustment, when the engine is
manufactured in its entirety, the operation of taking the pin out of one hole and
putting it in another is very simple. The tappet G¹ can also be adjusted so as not
to be in contact with the guide H; when the engine is worked in this manner the
action is extremely smooth, and a very high rate of speed can be obtained with
freedom from noise; at the same time there is considerable loss of power compared
with the results obtained when the tappet action is employed, since the greatest and
best pressures in the vessel B occur respectively at the end of each stroke. This
circumstance, however, renders the engine when adjusted in this manner especially
suitable for compressing or exhausting gases or vapours for refrigerating purposes, or
for purposes of ventilation, or for any purpose where the compression and rarefac-
tion of a gas or vapour would be useful.
To use the engine without the receiver the following adjustments should be
made: The bottom parts of the pipes X, O, p, and W should be disconnected
from the receiver Q, and be open to the atmosphere, the stop-cock and valves being
retained. The bottoms of the pipes T and t should also be disconnected from Q
and connected with two ordinary water tanks, the tank connected with the pipe T
being maintained supplied with water. The stop-cocks and check valves in these
pipes T and t should also be retained. The engine, when adjusted in this way, can
be worked in the manner already described, the ordinary external atmosphere per-
forming the same office as the artificial atmosphere formed in the receiver Q, and
the water being admitted and discharged in the manner herein-before described.
The working of the engine at the ordinary atmospheric pressure can also be very
simply effected by attaching a cock to the upper part of the receiver Q and leaving
it open.
When the engine is adjusted to work without the receiver Q and the tappet
action it can be employed to compress and rarefy gases and vapours. The operation
is very simple, the vessel holding the air (for example) to be rarefied, and that in
which the air is to be compressed should each be connected with the pipe O. The
vessel in which the air is to be rarefied being provided with a valve opening out-
wards, whilst that vessel in which compression is to take place is provided with a

page_text: valve opening inwards. On starting the engine the work of a pump will be per-
formed by the mere expansion and rarefaction of the air, gas, or vapour acted on.
If contact with water is injurious to the gas or vapour acted on any other suitable
liquid may be employed in substitution for water, or the pipes T and t should be
closed and the lower part of the vessel B should be jacketed and cold water caused
to circulate through the space formed by the jacket and the vessel B, the water
being admitted at the lower end of the jacket and leaving at the top of the jacket.
The engine thus jacketed at the cold end may also be used for ordinary motive-
power purposes, with or without the tappet action, and with or without the
receiver Q, and either with air or other gases at a high pressure in conjunction with
the receiver Q.
In the furnace it will be seen that the greatest heat is applied to the upper end
of the vessel B, and that this heat diminishes gradually as the gaseous products of
combustion travel in the direction of the arrows, it being absorbed by the vaporous
air in the vessel B. This distribution of the heat of combustion is very important
in an economical point of view, as nearly all the heat is utilized, since the upward
current of air and moisture in the annular space between the vessel B and the
cylinder L on one side of the vessel B meet the descending products of combustion
on the other side of the vessel B, whence it results that the air and steam gradually
absorb the heat until they require their maximum temperature, when they enter
-the upper end of the vessel B. The descending_products of combustion on the
other hand gradually diminish in temperature until they escape.
In certain situations in lieu of employing the furnace the upper end of the
vessel B can be jacketed, and any fluid that will bear a high temperature may be
caused to circulate through it, being admitted at the upper end of the jacket and
permitted to pass out at the lower end of the jacket, so that the greatest heat of the
fluid will be communicated to the upper end of the vessel B where it is most
wanted. The heating fluid medium in returning should enter the furnace at that
point where the gaseous products of combustion are escaping into the atmosphere,
the pipe or coil containing the heating medium travelling or being placed in the
flue to meet them. The coil should be caused to leave the furnace at the hottest
part and conducted to the jacket of the engine. If this arrangement is suitably
carried out the gases of combustion will leave the furnace at about the same tem-
perature that the heating medium enters it.
The circulation of the medium can be effected by the revolution of a screw
revolving in a vertical position connected with that part of the pipe where the
heating medium is about to enter the furnace. The vertical spindle of the screw
can revolve in a long vertical stuffing box, the bottom part of which is fitted to
receive the packing, and which can be kept cool by a water jacket. The stuffing
box containing the spindle although being in a direct line with the passage in
which the medium circulates does not form part of it, and will have but little
tendency to become heated, and can be easily maintained cool in the manner herein-
before described.
Superheated steam or heated gases may be used to circulate through the jacket
of the vessel B in the same manner under circumstances where their employment
would be convenient.
One part of the motion of the tappet action, as described is due to the friction
of the steel rings on the rod D, but this motion may also be produced by any of the
usual methods known, provided that the relative motions of the displacer C and the
piston I are the same as herein-before described.
Figure 3 shows a modified form of the vessel B and its contents, the cylinder L
being dispensed with. This arrangement may be used when the engine is intended
to be applied where a small amount of motive power is required. The regenerator
Z, Z, is attached to the displacer Cand moves up and down with it. The connecting
rod H¹ works direct from the plunger I without the intervention of a piston rod,
and is connected with the crank in the usual manner. The inlet and outlet is
regulated by the openings 8, 8, cut in the cylinder J. A way or passage E' is

page_text: formed in the plunger I, a port being cut into it from the outside of the plunger in
such a manner that it coincides with one of the ports 8, 8, at the termination of
each stroke. This port of the plunger I may be provided with a lining of metallic
packing exactly fitting in it and kept constantly forced outwards by a spring
pressing against it. At the end of the down stroke the air is discharged; at the
end of the up stroke it is admitted. The opening K may have a pipe attached to
it capable of working in a stuffing box and gland in the receiver Q, which may be
charged as herein-before described. The pipe T supplies the water to be injected
as herein-before described. The water is discharged with the air through the
passage E. The oil pot is connected with a passage in the side of the cylinder J.
When a partial vacuum is formed in the vessel B the oil is drawn up to the top of
the cylinder J, lubricating the plunger I. It is prevented from being forced out by
a valve opening inwards in the oil pot q. The oil may also be injected by any of
the approved lubricators now in use for similar purposes. gl is the lubricator for
the end of the connecting rod H³. By pressing an india-rubber ball or bag with
which the lubricator is provided the oil is forced up the pipe to the desired place;
when empty it may be filled through an opening in the ball provided with a
screwed cap arranged in such a manner that it can be taken off and replaced when
necessary. The engine may be stopped by opening a cock communicating with the
atmosphere, or with the receiver Q if it is used with the engine in this form.
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 application of a regenerator for the purpose of storing up and absorbing
the latent heat of the steam last used in the engine as it with the air passes over
its surface in one direction, and for giving up again the heat so stored to the water
to be converted into steam carried by the air travelling in the opposite direction.
Second. The system of cooling the air in hot-air engines by subjecting the air to
the direct contact with water.
Third. The application of an injection of water into the cylinder or vessel B for
the purpose of charging the air with moisture and cooling the interior metallic
parts of such cylinder or vessel by the direct contact with water, together with the
method of reutilizing the same water and causing the injection into the same
cylinder or vessel and the discharge from it to occur through variations of pressure
in it.
Fourth. Arranging the apparatus so that the upper ond of the vessel B shall be
in a hot condition and the lower end in a cool condition, whereby the difference of
temperature between the ends is more easily maintained, and also the mode of
applying the heat, substantially as herein-before described.
Fifth. The method of rarefying and condensing gases and vapours by the direct
intermittent expansions and contructions of portions of the gases and vapours
themselves, such intermittent expansions and contractions being the result of the
alternate action of heat and cold or changes of temperature.
Sixth. The application of air or other gas or gases of any density as a medium
for carrying the water in a finely divided state to the metallic surfaces of the
regenerator and other parts of the engine.
Seventh. The combination of the receiver Q with the other parts of the engine,
substantially as and for the purposes herein-before described.
In witness whereof, I, the said John Henry Johnson, have to this my Speci-
fication set my hand and seal, this Twenty-sixth day of March, One
thousand eight hundred and seventy-seven.
J. HENRY JOHNSON. (L.S.)