Improvements in and relating to Vapor and Ammonia Engines.
Year: 1890

page_text: COMPLETE SPECIFICATION.
Improvements in and relating to Vapor and Ammonia Engines.
I. JOSEPH HENDERSON CAMPBELL, of 35 Wall Street New York, County and
State of New York, United States of America, Engineer, do hereby declare, the
nature of this invention for "IMPROVEMENTS IN AND RELATING TO VAPOR AND
AMMONIA ENGINES," and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
My invention relates to aqua ammonia engines, wherein ammonia gas for propelling
an engine is expelled from aqua ammonia by heat, and the exhaust vapor is re-
absorbed by weak solution withdrawn from the generator wherein such heating takes
place, the combined absorbing liquid and exhaust vapor being thereupon forced back
into the generator.
The purposes of my invention are to provide methods and apparatus for accom-
plishing the following objects
1. To obtain proper circulation of steam whon it is used as the heating agent for
the purpose of expelling the gas from aqua ammonia in a generator and superheating
said gas, and to obtain proper circulation in the generator of the gas so expelled.
2. To so utilize, in operating a compound aqua ammonia engine, the heat con-
tained in weak solution drawn from the generator for the purpose of absorbing by
it the exhaust vapor of the engine, as to increase by it the temperature of the working
vapor after its leaving the high-pressure cylinder and before entering the low-
pressure cylinder.
3. To utilize the heat of absorption developed upon the union of exhaust vapor
and spraying liquid for the purpose of heating the feed liquid.
4. To accomplish absorption of the exhaust vapor by the spraying liquid in an
absorber along the exterior surfaces of a series of pipes or tubes arranged in a series
of communicating chambers, such pipes or tubes being cooled by the passage through
them of cold water or other refrigerating liquid.
5. To prevent the violent agitation of the aqua ammonia in a well communicating
with the atmosphere, or in that part of the well from which the feed pump takes its
supply for the generator and thus avoid a loss of ammonia vapor whether the
agitation is produced by the forcible entry of the combined exhaust vapor and
absorbing liquid or by air that has been carried over to said well.
6. To purge the aqua ammonia in the apparatus of air or in condensable gases,
automatically or otherwise.
7. To prevent oil or other foreign substances that have been carried into the well
from being forced into the generator by the feed pump.
The foregoing and other novel and important features of my invention will be fully
described hereinafter and pointed out in the claims.
In the drawings I have shown in Fig. 1 a longitudinal vertical view, partly in
section, of an apparatus embodying the various features of my invention, while
Fig. 2 represents a vertical cross-section of that part of the apparatus commonly
called the absorber, and Fig. 3 a vertical section, on an enlarged scale, of the receiving
well above referred to. Corresponding letters throughout the various views represent
corresponding parts.
A, is a steam boiler of ordinary construction, B, is a secondary boiler wherein
aqua ammonia is heated by water-steam. Such aqua ammonia boiler will hereinafter
be termed the generator. The same is so arranged that the water-steam generated in
boiler A, enters it through connection A, when the gate valve a₁ therein is open, and
after circulating through its tubes, will be drained back into the steam boiler. The
generator is provided with tubes above and below the liquid line and with steam
chambers 1, 2, 3, and 4 at its heads, and is so constructed that the steam entering

page_text: chamber 1, through connection A₁, will pass through the tubes ₁₁ to chamber 2,
then through tubes by by to clumber 3, and from there through tubes by be to
chamber from where it is drained back through connection Ag into the liquid space
of the boiler A., is check valvo in pipe A, opening downward.
Th lower tubes of the generator are surrounded by aqua ammonia. f, and f
are horizontal division plates to prevent the conveying of water with the vapor to
the engine, and to cause the gas to travel over the hated tubos in the vapor space in
direction opposite to that taken by the steam while passing through the tubes, that
the vapor may become superheatedl. In most cases the use of only one such plate
will be sufficient. Stomm having heen generated in the boiler A, as the valve a is
opened and the steam passes through generator B as indicated above, it will be
observed that while first going thr.gh the tubes in the vapor space, it will readily
superheat the vapor in the upper part of the generator, but that in passing finally
through the tubes in the lower or liquid space, the requirement of heat there being
much greater, a portion of the steam will be condensed and a circulation of steam
will be effected in this direction. A difference between the temperature of the vapor
in the upper part of the generator and in that of the liquid in its lower part is
maintained, and continuous circulation of the steam is produced by the withdrawal of
liquid so heated for the purpose of afterwards employing it in a cooled condition in
absorbing the exhaust vapor of the engine and returning it so cariched at a tempera-
ture lower than that maintained in the generator, by means of a pump.
The gas expelled from the solution is superheated as described and any liquid
carriol along with the gas will be vaporized before leaving the generator, for use in
the engine cylinder. The check valve ag in pipe Ag is to prevent the liquid from
being forced out of the boiler into the generator when the valve a is closed, said
pipe A, reaching into the liquid space of steam boiler A. (is the main vapor valve
of the generator and the throttle-valve of the engine. Dis the vapor pipe for
supplying vapor to the cylinder of the engine and in compound engines, as in this
case, to the high-pressure cylinder E, from which the exhaust vapor is discharged into
the reservoir F, and from where it passes through the pipe G into the low-
w-pressure
cylinder H, and having performed its work there is discharged into pipe L. is a
pipe conveying the absorbing liquid from the generator B, to the exhaust pipe of
eylinder H, where it discharges the liquid by means of the jet J. ( is a cock for
regulating the discharge through said jet J. Said pipe is mado to pass through
reservoir in form of a coil. It there imparts heat to the vapor which has just leit
cylinder E, where anch vapor has lost part of its heat owing to its expansion therein.
From reservoir F, the spray pipe I passes, again in the form of a coil through
reservoir K, where it is further reduce in temperature by cooling water surrounding
said coil. Pipe It is used for supplying such water and K, for withdrawing it from
casing K. The combine 1 spraying liquid and exhaust vapor pass through exhaust.
pipe Linto chamber M acting as a heater for the feed liquid, as hereafter described,
and constructed as a surface condenser. After passing through the tubes m, m of
said heater M the absorbing liquid, together with the exhaust vapor enter absorber N
through pipe O. They are withdrawn from the absorber by vacuum pump through
pipe S. Said absorbier has a double head at each end, formed by bonnets Q
and Q boltod on to the main body of the absorbed. It is furnished throughout
with a series of longitudinal tubes N₁ Ng Ng Ng Ng Ng nnnng which at each end
open into the water ways formed by the double heads. The space at each end of the
absorbor formed by the bonnets Q₁ and Q is divided into such water ways 5, 6, 7, 8
and 9 by partitions and is the pipe through which the cooling water
enters the absorber and r, is the pipe discharging such water from the absorber.
These partitions correspond in location and height with diaphragms or division
plates 0, 0, and O, each of which extends entirely across the interior of the absorber,
and extends lengthwise from one end nearly to the other end, diaphragms O, and 0,
being attached to the tube head at the left end where partitions and q, aro located,
and diaphragm O, to the tube head on the right and where partition is located.
By this arrangement the interior of the upper part of the absorber is divided into

page_text: four communicating chambers, and spaces t₁, t, and t, are left at the ends of the
diaphragms for the free passage of any liquid or gas which has not found its way
from one of the upper chambers to another through the perforations p, p, of the
diaphragms, which are shown to be provided in the same. As before stated, liquid
and vapor combined enter the upper chamber of the absorber or that portion
traversed by the tubes n₁₁ and are carried downward partly owing to the weight
of the liquid and the constant reduction in the space occupied by the free gas in
the lower part of the absorber produced by its continued absorption, and partly
owing to the action of the vacuuin pump P, before mentioned, which pump through
pipe S, discharges into well W, the gas being more and more absorbed by the liquid,
as they become more intimately mixed and the liquid becomes cooler. A portion
of the liquid and gas passes through the perforations in the diaphragm O, and the
remainder passes through the space at the end of the diaphragm into the next
division, and so on, down to the division of the absorber containing tubos n n
and thence the liquid, having become cooled, and having absorbed a large proportion
of the gas enters the lowest compartment of the absorber where further absorption
takes place and which is constructed as hereinafter described. O, is an L shaped
plate, extending entirely from one end of the interior section of the absorber to the
other, covering the exit pipe, and so close to the bottom of the vessel that only a
narrow space remains between its lower edge and the bottom plate of the absorber.
Inside of the space thus enclosed by the shaped plate is an upright plate O, attached to
the bottom of the absorber, and extending nearly up to, but not quite touching, the lower
side of the horizontal part of the L shaped plate O,. This construction is shown
clearly in Figure 2. The effect of this arrangement is that the space enclosed by
the shaped plate and the upright plate O, is constantly filled with liquid to the
height of the upper edge of the upright plate O, and that, as no gas can escape but
through the exit pipe S (the mouth of which is enclosed by the shaped plate O₁)
all free gas attempting to pass out of the absorber must enter the space enclosed by
the shaped and upright plates 0, and O, and pass through the body of liquid
imprisoned therein. A gas trap is thus formed through which no free gas can
escape, and if it accumulates sufficiently to force its way through the water, tho
quantity is so small that it cannot escape absorption by the liquid if that be
sufficiently cool.
A practical test of this improvement has demonstrated its efficiency to secure the
desired result.
I have described the absorber to which my improvement is applied as having
tubes and diaphragms, but these are not necessary to the operation of my improve-
ment, but add to its efficiency by tending to secure a more perfect absorption of the
gas with the absorbing liquid.
Instead of completing absorption of the gas in the body of liquid confined
between plates O, and Ŏ, as described, an independent second absorber might be
employed wherein free gas might be made to pass through a body of such liquid
kept cool by cooling water circulating through it by means of proper tubes.
S, is the discharge pipe of vacuum pump P. Such pipe connects with pipe T, in
well W near its bottom and projects upward sufficiently so as to discharge its contents
in the upper part of the well. ₁ is the suction pipe through which feed pump pl
withdraws liquid from the well for the purpose of forcing it through pipe us,
heater M and pipo u, back into generator B. The well Wis cylindrical in form
having within it a cylindrical casing T₂, provided at its upper end with a riu
extending outward sufficiently so as to rest upon and be attached to a ring R attached
to the inner side of the walls of well W, the ring and the rim forming an air-tight
joint. Said casing T, is open at its top and bottom and reaches downward nearly to
the bottom of the well W, leaving, however, a space sufficient for the free passage of
liquid from the interior of casing T, to the part of well W surrounding it. T, is a
cylindrical casing closed on top and open at its bottom, pipe T, passing upward
into such casing T, to within a short distance of the disk which closes its upper end.
x. x. are bolts passing through the top of well W. I l are lugs rigidly attached to

page_text: easing T The bolts .. .. are made to pass loosely through said lugs as shown, so
as to utilize said bolts as guides for casing T, YY are spiral springs surrounding
the lower parts of bolts... and resting on the heads of snch bolts or on washers
supported by said heads. Said springs serve to counteract the violent shock which
would otherwise be produced by the dropping down of casing T, after the same had
suddenly been elevated by the force of any air or gases discharged against its head
by vacuum pump P., is a pipe for the escape of air from the upper part of woll W
and T, is a pipe provided with a suitable cock C, and extending through the walls of
well W and inner casing T
In operation, the engine having been started, the exhaust ammonia gas, air, and
incondensable gases pass through the absorbers, are withdrawn by the vacuum pump
and forced by the same into the well through pipes S, and T. The ammonia gas
having been absorbed by the accompanying liquid before it reaches the outlet of
pipe Tor at that point, the force of the liquid and the pressure of the air and incon-
densable gases operate against the top of casing T, and their force is ordinarily
neutralized by the weight of said casing.
The liquid discharged from pipe T₁ passes down within the body of casing T, and
out of its bottom into that part of casing T surrounding the lower part of said
easing T without violently agitating the liquid in this part of the well. The liquid
surrounding the casing T, is generally higher than the liquid within such casing,
This is due to the pressure of the air, and incondensable gases within said
casing T. When the engine remains standing for a considerable time, or the
generator or engine has been opened, or if from any cause a large amount of
air has been drawn into the apparatus so as to reach the vacuum pump after
the engine has been started, this quantity of air will force the easing T, upward
and the liquid in easing T₂ downward and will thus make a free passage
for the air to the atmosphere between the casings T, and T. Ordinarily the
amount of air discharged into the well while the engine is running will not be
sufficient to force easing T, upward but will force the liquid in casing T, downward
and thus permit the air to escape through the same passage between the casings T
and T
Free gas that may be forced through said passage will be absorbed by the
liquid between casings T₂ and T, and the air will be forced upward passing between
the walls of well Wand casing T until it reaches and is discharged through air pipe T..
While, when the engine is operated with ammonia gas no oil is required for
lubricating the interior of its eslinder and valve chest, it frequently occurs that oil
remaining over in such cylinder since the time when the same was last operated by
steam enters the absorbing apparatus through the exhaust pipe. Such oil when in
contact with ammonia and subject to vory high temperatures will form a com-
bination with it, that will materially interfere with the proper development of vapor
from the solution. It therefore becomes necessary to withdraw such oil from the
apparatus before it enters the generator. This is accomplished in the well as follows:
Such oil will pass downward with the air within easing T, and, being lighter than
aqua ammonia, will rest on the surface of the liquid in ensing Te from which place it
may readily be withdrawn through pije T, after cock C, therein has been opened.
The annular space existing in well W around the upper part of casing T, and above
the suction pipe u of the feed pump furnishes room for the liquid when forced in
unusual quantity out of cusing T, and before the same can be taken by the foed
pump. is a vertical glass tube, its upper end being connected with the air space
surrounding casing T, in the well and its lower end being connected by a suitable
pipe with the inner casing T, at a point slightly lower than that where the drain
pipe T communicates with said easing T, Thus, whenever oil or similar sub-
stances fill the upper part of casing T, they will enter said glass tube Z from its
bottom and their presence can in this manner be observed, and they may be removed
by opening valve C. It will be seen that with a slight modification cusings T,
and T might be placed on the line of pipe S, before the same enters the well and hy
properly connecting the same with the well, would perform the same functions as
specified above. They are shown within the well as this offers a simple and convenient

page_text: form of construction, and it is also evident that the well could be divided into two
parts by a central partition, and one part might be made to receive the incoming
liquid and to serve to separate the air from it, while the second part of such well
made to supply the feed pump, but the construction as shown is preferred, but not
essential. As explained before, the feed pump P₁ withdraws the liquid from the well
and forces it first through pipe into the space surrounding the tubes m min
beater M, where the feed liquid takes up heat of absorption developed therein, and
afterwards through pipe u, (having check valve w, closing towards the generator) back
into such generator.
is a branch pipe leading out of pipe, into the valve chest of engine cylinder E.
Such pipe is provided with a cock C, for admitting the feed liquid so heated in
heater M to the valve chest and cylinder at such times as such lubrication seems
especially called for. This will occur particularly upon starting the engine. Obtaining
such lubricating liquid from pipe ", offers the advantage that a strong solution can
thus always be obtained under a greater pressure than any pressure that will ever
occur in the engine cylinder.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what I
claim is :-
1. The method herein described of operating an aqua ammonia engine, the same
consisting in passing steam from a steam boiler directly through the tubes of a super-
heating chamber of a generator, causing it afterwards to circulate through tubes in
the liquid space of said generator, expelling by the heat of such steam, ammonia gas
from aqua ammonia surrounding said tubes, then conveying said gas to the cylinder
of an engine and propelling its piston by such gas afterwards exhausting said gas and
bringing it in contact with weak solution withdrawn from the generator, cooling the
combined gas and solution, returning the same to the liquid space of the generator
and causing the steam condensed thereby to return to the steam boiler, substantially
as set forth.
2. The method herein described of operating an aqua ammonia engine, the same
consisting in passing the steam from a steam boiler through tubes of the generator
communicating with each other, part of said tubes being surrounded by vapor and
part of the same being surrounded by liquid, thus expelling ammonia gas and super-
heating it by the heat of the steam, then conveying said gas to the cylinder of an
engine, cooling it by working expansively, exhausting the same, bringing the
exhaust vapor in contact with weak solution drawn from the generator, cooling the
combined vapor and solution, returning the same to the liquid part of the generator
and causing the steam condensed thereby to return to the steam boiler by gravity,
substantially as set forth.
3. The method herein described of preventing the liquid in the ammonia generator
from being drawn over into the engine cylinder and of promoting the heating and
superheating of the gases expelled from the liquid in such generator, the same con-
sisting in inserting in said generator a horizontal or lateral diaphragm, extending over
part of the vapor space in said generator, thus compelling lateral motion of the gases
in said generator, substantially as set forth.
4. The method herein described of preventing liquid from being drawn over from
an ammonia generator into the engine cylinder and of promoting the heating and
superheating of the gases expelled from the liquid in an ammonia generator, having
double heads at its ends and tubes connecting the same, said method consisting in
subdividing the end chambers by inserting therein diaphragms having directions
corresponding with that of the tubes aforesaid, and in inserting a lateral diaphragm in
the central part of said generator, but extending it only from a side wall of the
vapor space across part of its width, for the purpose of changing the direction of the
steam for heating the contents of the generator while circulating through the same,
and of compelling circulation of the ammonia vapor in a direction different from that
taken by the steam while passing through said tubes, substantially as set forth.

page_text: 5. The method herein described of utilizing heat of the spraying liquid withdrawn
from the generator of a compound aqua animonia engine, which consists in heating
the vapor in an intermediate chamber between the high and low pressure cylinder,
by hot weak solution drawn from the boiler for spraying the exhaust vapor, substan
tially as set forth.
6. The method herein described of utilizing heat of absorption evolved in an aqua
ammonia engine, for the purpose of heating the feed liquid, which consists in bringing
the cooled weak solution and the exhaust of the engine in contact with each other and
thus generating heat of absorption, and causing the combined vapor and liquid to pass
around passages containing the foe 1 liquid after it has passed through the feed pimp
on its way to the generator, thus heating said feed liquid, substantially as set forth.
7. The method herein described of cooling the combined spraying liquid and
exhaust vapor of an aqua ammonia engine, which consists in passing the same through
a surface condenser on its way to the feel pump and using the saturated liquid as a
cooling medium within said surface condenser, while passing said saturated liquid
from the feed pump to the generator, substantially as set forth.
8. The method herein described of providing strong heated solution of ammonia
as a lubricant for the cylinder of an aqua ammonia engine, which consists in uniting
the exhaust vapor of the engine and absorbing liquid, passing the same combined
through a feed pump, heating the feed liquid alter it has passed said pump and
conveying such liquid into the valve chest or cylinder of said engine, substantially as
set forth.
9. The method herein describes of operating an ammonia engine, consisting in
subjecting aqua ammonia to heat in a generator to separate the gas therefrom, passing
the gas thus generated to a vapor engine to operate the same, and passing some of
the weak solution remaining in the generator (which is preferably partially cooled on
its passage) to the exhaust pipe of the engine, causing the mingled gas and weak
solution to traverse the exterior surfaces of a series of pipes or inbes cooled by the
passage through them of cold water or other refrigerating liquid, such pipes being
arranged in a series of communicating chambers, partially separated by diaphragms,
to effect a more perteet cooling of the absorbing liquid and a more complete absorption
of the gas, and returning the strong solution thus obtained to the generator to maintain
the supply of aqua ammonia, substantially as described.
10. The method herein described of operating an aminonia engine, consisting in
subjecting aqua ammonia to heat in a generator to separate the gas therefrom, passing
the gas thus generated to a vapor engine to operate the same, and passing some of
the weak solution remaining in the generator (which is preferably partially cooled in
its passage) to the exhaust pipe of the engine, causing the mingled gas and weak
solution to traverse the exterior surfaces of a series of pipes or tubes cooled by the
passage through them of cooled water or other refrigerating liquid, such pipes being
arranged in a series of communicating chambers partially separated by diaphragms,
to effect a more perfect cooling of the absorbing liquid and a more complete absorption
of the gas, and introducing it into a second absorber below the liquid line prior to
returning the strong solution thus obtained to the generator to maintain the supply
of aqua ammonia therein, substantially as set forth.
11. The method herein described of preventing agitation in the feed well of an
aqua ammonia engine apparatus, which consists in directing the combined exhaust
vapor and absorbing liquid towards a resisting device so as to reduce the momentum
of the inflowing solution after its leaving the main supply pipe and before its com-
mingling with the main body of liquid within the receiving well, substantially as set
forth.
12. The method heroin described of preventing agitation in the feed wall of an
aqua ammonia engine apparatus which consists in conveying the combined exhaust
vapor and absorbing liquid into the upper part of said well, causing the solution
discharged there to impinge upon a resisting device which overcomes the momentum
of such solution and deflects it so as to compol its passage through the main body of
the liquid within said well, substantially as set forthi.

page_text: 13. The method herein described of preventing agitation in the feed well of an
aqua ammonia engine apparatus which consists in conveying the combined exhaust
vapor and absorbing liquid into the upper part of said well, causing the solution
discharged there to impinge upon a resisting device which overcomes the momentum
of such solution and deflects the same so as to direct it downward into the lower part
of the well from where it rises towards the suction pipe of the feed pump, substantially
as set forth.
14. The method herein described of preventing agitation in the feed well of an
aqua ammonia engine apparatus which consists in dividing the receiving well into two
parts, destroying or neutralizing the momentum of the inflowing solution in one of
said parts, and afterwards compelling the flow of sue liquid by gravity into the other
part of said well, substantially as set forth.
15. The method herein describe of purging an aqua ammonia engine apparatus
of air, which consists in separating the combined exhaust vapor and absorbing liquid
from the air by gravity, storing or permitting the air to escape by suitable apertures
and causing the combined vapor and absorbing liquid to pass through the main hody
of liquid within the well, from which body the feed liquid for the generator is supplied,
substantially as set forth.
16. The method herein described of automatically purging an aqua ammonia engine
apparatus of air, which consists in separating the combined exhaust vapor and
absorbing liquid from the air by gravity, causing the air so separated to enter a
movable air chamber, and by its pressure to lift said air chamber so as to make its
interior communicate with the atmosphere outside of the well, substantially as set
fortli.
17. The method herein described of automatically purging an aqua aminonia engine
apparatus of air which consists in separating the combined exhaust vapor and
absorbing liquid from the air by gravity, causing the air so separated to enter a
suitable air chamber having a liquid seal which the pressure of the air within said
chamber removes or forcos back, thereby opening communication between the
interior of said air chamber and the atmosphere outside of the well, substantially as
set forth.
18. The method herein described of automatically purging an aqua ammonia
engine apparatus of air, which consists in separating the combined exhaust vapor and
absorbing liquid from the air by gravity, causing the air so separated to enter an
air chamber, and to force the liquid therein into the main body of the well and thereby
opening communication between the interior of the air chamber and the atmosphere,
substantially as set forth.
19. The method herein described of enforcing absorption of free ammonia gas
within the receiving well of an aqua ammonia engine apparatus, which consists in
confining such gas under a movable casing and utilizing the weight of such casing
for forcing said gas into the liquid contained in said well, substantially as set forth.
20. The method herein described of preventing air from being drawn into the feed
pump of an aqua ammonia engine apparatus, the feed being taken from a well having
communication with the atmosphere, the same consisting in dividing the well into
three parts so arranged that one of these parts located above the supply pipe, by
the pressure of the air on the liquid in the second part, opens a communication
with the atmosphere, the air delivered in the first or upper part being prevented
from reaching the main body of liquid in the third part from which the feed pump
takes its supply, by a body of liquid in the second part of said well, substantially as
set forth.
21. The method herein described of operating an aqua ammonia engine apparatus,
which consists in expelling ammonia gas from aqua ammonia in a generator by
heat, conducting such gas to the engine cylinder for propelling its piston, with-
drawing weak solution from said generator, cooling it and conducting it to the
absorbing apparatus of the engine, wherein the exhaust vapor from the engine and
such liquid are brought in contact with each other and cooled, employing a vacuum
pump for withdrawing the contents of such absorbing apparatus and delivering the

page_text: same into a well normally communicating with the atmosphere, and withdrawing tho
feed liquid from suid well by a feed pump, substantially as set forth.
22. The method herein described of operating an aqua ammonia engine apparatus,
which consists in expelling ammonia gas from aqua ammonia in a generator hy heal,
conducting such gas to the engine cylinder for propelling its piston, withdrawing
weak solution from said generator, cooling it and condnating it to the absorbing
apparatus of the engine wherein the exhaust vapor from the engine and such liquid
are brought in contact with each other and cooled, employing a vacuum pump for
withdrawing the contents of such absorbing apparatus, and for delivering the same
into a well normally communicating with the atmosphere, parging the combined
exhaust vapor and absorbing liquid of air prior to minging the same with the main
body of liquid in said well, and finally forcing such liquid back into the generator,
substantially as set forth,
23. The method herein described of operating an aqua ammonia engine apparatus,
which consists in expelling ammonia gas from aqua ammonia in a generator by heat,
conducting such gas to the engine cylinder for propelling its piston, withdrawing
weak solution from said generator, cooling it and conducting it to the absorbing
apparatus of the engine wherein the exhaust vapor from the engine and such liquid
are brought in contact with each other and cooled, withdrawing the contents of
such alsorbing apparatus by conducting the same into a well normally communi-
cating with the atmosphere, purging the combined exhaust vapor and absorbing
liquid of air prior to mingling the same with the main holy of liquid in said well
and finally forcing such liquid back into the generator, substantially as set forth.
Dalal thin the ..
JOSEPH HENDERSON CAMPBELL.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicant.