IMPROVEMENTS IN ROTARY ENGINES
Year: 1859

page_text: LETTERS PATENT to Thomas Ivory, of Edinburgh, Advocate, for the
Invention of "IMPROVEMENTS IN ROTARY ENGINES."
Sealed the 15th September 1859, and dated the 31st March 1859.
PROVISIONAL SPECIFICATION left by the said Thomas Ivory at the
Office of the Commissioners of. Patents, with his Petition, on tho
31st March 1859.
I, THOMAS IVORY, of Edinburgh, Advocate, do hereby declare the naturo
of the said Invention for "IMPROVEMENTS IN ROTARY ENGINES," to be as
follows:-
In the first place, in impulse rotary engines as hitherto constructed, the
steam or other impelling fluid is made to act on a revolving piston at or near
the circumference of the circle of revolution, and the sectional area of the
steam channel within which the piston travels is the measure of the area of
effective pressure on the piston.
Now, the principle or nature of this first part of my Invention consists in
causing the impelling fluid, while admitted at the circumference, to act directly
and effectively on an area near the centro of the circle of revolution, and
so arranging the parts of an impulse rotary engine as to produce this effect.
The effective area near the centre is in this case not limited in extent by
the sectional area of the steam channel within which the outer end of the
revolving arm hereinafter described travels, but is capable of being made much
larger. For this purpose I use a hollow revolving arm, the inner end of which
is all on one side of the centre of revolution, and this arm is mounted so that
its outer end, or a portion thereof, works within a fixed ring, having flanges

page_text: covering the said outer end or portion, and between which the same may
travel. The hollow arm is open to the inner circumference of the fixed ring,
and has at the outer extremity of its side nearest the centre of revolution an
orifice forming a communication between the channel hereinafter described
and the interior of the hollow arm. This side of the arm has connected with
it a kind of tail or appendage, the outer circumference of which is concentric
with the circle of revolution.
There is a stop provided near the induction passage, and capable of being
moved into or across the channel formed by the flanged ring and tail. These
several parts are to be so arranged that they form a closed channel so as to
prevent the escape of the impelling fluid out of the channel until the extremity
of the tail or appendage has passed the stop or abuttal.
purpose of
The impelling fluid is admitted for the purpose of acting on the arm by an
induction passage through the ring or its flanges between the said stop or
abuttal and the open arm. In this way the fluid, having no escape in the
direction of the stop, is made to force back the arm. For the
producing and maintaining a continuous rotary motion when a single hollow
arm is used, the outer circumference of the tail should include rather more
than a semicircle, and a second stop is provided similar to that above men-
tioned on the opposite side of the ring. These stops are moved into or across
the said channel at the required intervals of time by any suitable mechanism
connected with the engine, and also similarly withdrawn for the purpose of
allowing the arm to pass. These stops are intended to remain inserted to
their full extent through the ring, except when they are necessarily withdrawn
for the above purpose.
A second induction passage is also provided on the opposite side of the ring,
and the arrangement of this induction passage in relation to the second stop is
in all respects similar to that of the first induction passage in relation to the
first stop. Each of these induction passages is furnished with a valve, and
these valves are to be so worked by mechanism connected with the engine,
as that when the one passage is opened the opposite one is closed at the
required intervals with reference to the proper admission of the fluid into
the arms.
I have merely, for the sake of simplicity, described the arrangement for
producing continuous rotary motion with one arm, but it is contemplated that
two or more arms may be employed. In the latter case, the tail attached to
each arm extends back to rather more than half the distance between the
orifice of such arm and that of the next following arm, and the requisite
induction passages and stops are provided for these arins..

page_text: And my Invention consists, in the second place,. in an arrangement for
working expansively the steam or other elastic fluid used in engines of tho
above description. This is accomplished by opening in the outer ring, or in
one or both of its flanges behind the stop used for the high-pressure arm, a
communication through which the steam or other elastic fluid may expand
either into another revolving arm or into another circular flanged channel with
a revolving piston, such arm or piston having the same axis of rotation as tho
high-pressure arm. The arrangement for working the expansion arm or the
piston is similar to that described under the first part of my Invention. The
expansion stops, which are on the opposite sides of the communication with
the high-pressure channel from those used for the high-prossure arm, are or
may be worked independently of the high-pressure stops, but by similar
suitable mechanism. In engines of the kind now described, while the tail on
the expansion side extends, as in the first described engine, to rather more
than half the distance between the orifice of each arm and that of the next
following, the tail or appendage on the high-pressure side, extends from the
orifice of each arm to nearly the back of the next following arm. In this
case, also, one or more high-pressure arms and one or more expansion arms or
pistons may be employed.
The expansive use of the steam or other elastic fluid may also be accom-
plished without a separate expansion sido by having only ono induction
passage and valve, such valve being closed as soon at least as the hollow arm
has passed the stop at which it first arrives after passing the said induction
passage. In this case the clastic fluid, which acts expansively, is that enclosed
within the hollow arm.
My Invention consists, in the third place, in adapting and applying to
impulse rotary engines, in which a solid piston is made to travel within a
steam channel, the above described arrangement of stops and tail, and also
the expansion arrangement first described.
My Invention consists, in the fourth place, in adapting and applying the
above described arrangement of flanged ring, stops, and tail, and also the
expansion arrangement to the recoil engines described in the Specification of
my Patent bearing date Thirtieth July One thousand eight hundred and fifty-
seven. In this case the induction passages and valves are dispensed with,
and the steam or other impelling fluid is admitted to the arms through a
hollow axle.
My Invention consists, in the fifth place, in obtaining an increased effect
from the motive fluid in engines on the Barker's mill principle by means of
an external fixed ring, and an arrangement of flanges, stops, and tail, and'

page_text: expansion arrangements similar to those above described. The only difference
between the arrangement applicable to these engines and those last referred
to is, that in the Barker's mill engines the arm is closed towards the outer
ring.
And my Invention consists, in the last place, in obtaining the expansion use
of elastic fluids in impulse rotary engines by means of a hollow arm or chamber
opening into a steam channel at the circumference. The arrangement for
accomplishing this is in all respects similar to that described, under the second
head of my Invention for obtaining the expansive use of the elastic fluid
without a separate expansion side, except that in this case the, form and mode
of mounting of the hollow arm is not limited as in the former case.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Ivory in the Great Seal Patent Office on the
30th September 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
IVORY, of Edinburgh, Advocate, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirty-first day of March, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-second year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Thomas Ivory, Her special license that I, the said Thomas Ivory, my
executors, administrators, and assigns, or such others as I, the said Thomas
Ivory, my executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during
the term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
ROTARY ENGINES," upon the condition (amongst others) that I, the said Thomas
Ivory, by an instrument in writing under my hand and seal, should particularly.
describe and ascertain 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
Scal Patent Office within six calendar months next and immediately after
the date of the said Letters Patent.
NOW KNOW, YE, that I, the said Thomas Ivory, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-.
formed, to be particularly described and ascertained in and by the following

page_text: statement, reference being had to the Drawings hereunto annexed, and to the
letters and figures marked thereon (that is to say):
:
My Invention of "Improvements in Rotary Engines" consists in the several:
arrangements and constructions thereof herein-after described. In the first
place in impulse rotary engines, as bitherto constructed, the steam or other
impelling fluid is made to act on a revolving piston at or near the circum-
ference of the circle of revolution, and the sectional area of the steam channel,:
within which the piston travels, is the measure of the area of effective pressure
on the piston.
Now, the principle or nature of this first part of my Invention consists in
causing the impelling fluid, while admitted at the circumference to act directly
and effectively on an area near the centre of the circle of revolution, and in so
arranging the parts of an impulse rotary engine as to produce this effect.
The effective area near the centre is in this case not limited in extent by
the sectional area of the steam channel, within which the outer end of the
revolving arm herein-after described travels, but is capable of being made
much larger. For this purpose I use a hollow revolving arm, the inner end of
which is all on one side of the centre of revolution, and this arm is mounted
so that its outer end or a portion thereof works within a fixed ring having
flanges covering the said outer end or portion, and between which the same
may travel. The hollow arm is open to the inner circumference of the fixed
ring, and has at the outer extremity of its side nearest the centre of revolution
an orifice, forming a communication between the channel herein-after described
and the interior of the hollow arm. This side of the arm has connected with
it a kind of tail or appendage, the outer circumference of which is concentric
with the circle of revolution.
There is a stop provided near the induction passage, and capable of being
moved into and across the channel formed by the flanged ring and tail. These
several parts are to be so arranged that they form a closed channel, so as to
prevent the escape of the impelling fluid out of the channel until the extremity
of the tail or appendage has passed the stop or abuttal.
The impelling fluid is admitted for the purpose of acting on the arm by an
induction passage through the ring or its flanges, between the said stop or
abuttal and the open arm. In this way, the fluid having no escape in the
direction of the stop is made to force back the arm. For the purpose of pro-
ducing and maintaining a continuous rotary motion when a single hollow arm
is used, the outer circumference of the tail should include rather more than a
semicircle, and a second stop is provided similar to that above mentioned on
the opposite side of the ring. These stops are moved into or across the said

page_text: channel at the required intervals of time by any suitable mechanism connected
with the engine, and also similarly withdrawn for the purpose of allowing the
arm to pass. These stops are intended to remain inserted to their full extent
through the ring, except when they are necessarily withdrawn for the above
purpose.
A second induction passage is also provided on the opposite side of the ring,
and the arrangement of this induction passage in relation to the second stop is
in all respects similar to that of the first induction passage in relation to the
first stop. Each of these induction passages is furnished with a valve, and
these valves are to be so worked by mechanism connected with the engine as
that when the one passage is opened, the opposite one is closed at the required
intervals with reference to the proper admission of the fluid into the arms.
I have merely for the sake of simplicity described the arrangement for
producing continuous rotary motion with one arm, but it is contemplated that
two or more arms may be employed. In the latter case, the tail attached to
each arm extends back to rather more than half the distance between tho
orifice of such arm and that of the next following arm, and the requisito
induction passages and stops are provided for these arms.
And my Invention consists, in the second place, in an arrangement for
working expansively the steam or other elastic fluid used in engines of the
above description. This is accomplished by opening in the outer ring or in
one or both of its flanges, behind the stop used for the high-pressure arm, a
communication through which the steam or other elastic fluid may expand,
either into another revolving arm or into another circular flanged channel with
a revolving piston, such arm or piston having the same axis of rotation as the
high-pressure arm. The arrangement for working the expansion arm or the
piston is similar to that described under the first part of my Invention. The
expansion stops which are on the opposite sides of the communication with
the high-pressure channel from thoso used for the high-pressure arm, are or
may be worked independently of the high-pressure stops, but by similar suitable
mechanism. In engines of the kind now described, while the tail on the
expansion side extends as in the first described engine, to rather more than
half the distance between the orifice of each arm and that of the next
following, the tail or appendage on the high-pressure side extends from the
orifice of each arm to nearly the back of the next following arm. In this
case also one or more high-pressure arms and one or more expansion arms or
pistons may be employed.
The expansive use of the steam or other elastic fluid may also be accomplishe:l
without a separate expansion side, by having only one induction passage and

page_text: valve, such valve being closed as soon at least as the hollow arm. has passed
the stop at which it first arrives after passing the said induction passage. In
this case the elastic fluid which acts expansively is that enclosed within the
hollow arm.
My Invention consists, in third. place, in adapting and. applying to impulse
rotary engines in which a solid piston is made to travel within a steam
channel, the above described arrangement of stops and tail, and also the
expansion arrangement first described.
My Invention consists, in the fourth place, in adapting and applying the
above described arrangement of flanged rings, stops, and tail, and also the
expansion arrangement to the recoil engines described in the Specification of
my Patent bearing date Thirtieth July, One thousand eight hundred and
fifty-seven. In this case the induction passages and valves are dispensed
with, and the steam or other impelling fluid is admitted to the arms through a
hollow axle.
My Invention consists, in the fifth place, in obtaining an increased effect
from the motive fluid in engines on the Barker's mill principle, by means of
an external fixed ring, and an arrangement of flanges, stops, and tail, and
expansion arrangements similar to those above described. The only difference
between the arrangement applicable to these engines and those last referred to
is, that in the Barker's mill engines the arm is closed towards the outer ring.
And my Invention consists in the last place, in obtaining the expansion use
of clastic fluids in impulse rotary engines, by means of a hollow arm or
chamber opening into a steam channel at the circumference. The arrange-
ment for accomplishing this is in all respects similar to that described under
the second head of my Invention for obtaining the expansive use of the elastic
fluid without a separate expansion side, except that in this case the form and
mode of mounting of the hollow arm is not limited as in the former case.
.
Having thus stated the nature of the said Invention, I will proceed to
describe more particularly in what manner the same is to be performed by
reference to the accompanying Drawings, which are Diagrams illustrating my
said inprovements, and representing the several main operative parts of the
rotary engines above referred to. In the several Figures the same letters of
reference indicate corresponding parts.

page_text: which the arm B travels, such ring having flanges covering the outer end of
the arm; C is a tail or extension of the arm, reaching backwards rather more
than a semicircle; D, D', are induction passages for the impelling fluid, one
of each of which is inserted in a valve box on each side of the ring, both of
which passages are in communication with the steam pipe; E, E', are valves,
which are made to open and close the passages for the impelling fluid, as
hereafter described; F is the stop, which when thrust into the ring is made to
form an abuttal for the impelling fluid entering by the passage D; and F is
a corresponding stop on the other side of the ring, having a similar relation to
the passage D'. The valves E, E', aro worked by the cam G on the main
shaft, acting on a stud on each respectively at the required interval, and the
two valves are rigidly connected together, so that whon one is thrust out of
the valve box to open the passage for the impelling fluid, the opposite one is
drawn in to close the passage for the same on the opposite side of the ring.
This mechanism for working the valves is shown by dotted lines, but they may
be worked by other means. The rigid connections between the valves are
shown at H working in guides I, I. The stops F and I are worked by
another cam or a different plane, but on the same shaft, the cam in liko
manner acting as required on a stud fixed in each stop, so as to force the
stops alternately out of the ring or steam channel at the required interval, in
order to let the arm pass a spring, being fixed so as to return the stop as soon
as the pressure thereon of the cam has ceased. The stops may, however, bo
returned, or be assisted in being returned into the channel by the pressure of
water or steam admitted behind them from the valve box acting directly at
their back part, or acting on them through a piston in a small cylinder. This
mechanism for working the stops will be readily understood by a competent
mechanic without the aid of a Drawing. The stops may also be worked by
other suitable means. The working of the engine is as follows:-On the
impelling fluid being admitted at the induction passage D, it will pass into the
arm B, as indicated by the arrow (Fig. 1), and being obstructed by the stop F
will be made to exert its impelling force on the arm at the inner end near the
centre of revolution, the area of effective pressure being denoted by the
letters a, b. By the revolution of the arm in the direction of the arrow, the
channel formed by the tail C will become filled with the fluid, and this will
continue until the side of the arm nearest the stop F' has passed that stop
which has become forced out of the channel by the cam provided for tho
purpose. After which, as soon as the induction passage D' and the open arm
Bare so situated, that the whole of that passage opens into the arm, the
forcing outwards of the valve E¹ by the action of the cam G thercon begins

page_text: This has the effect of beginning to close the induction valve E at the other
side of the ring through the connections H, H, and when the arm B has the
same relative position to the stop F' (this stop having been by this time
returned to its place so as to act as a stop), which it is represented in the Figure
as having to the stop F, the valve E¹ is fully opened, and the valve E fully
closed. The fluid then enters fully by the passage D¹, and the stop F¹ then
acts as an abuttal for the fluid. In this manner the revolving arm B is forced
round continuously. The waste fluid will escape out of the arm as soon as
the end of the tail C has passed the stop F; but this it will be seen cannot
take place until the valve E' is fully opened, and the valve E entirely closed.
It will be seen that the arm is thus continuously impelled by the same amount
and pressure of fluid.
.
:
From the foregoing description of the rotary motion produced by a single
arm, it will be understood that when two or more revolving arms are used,
the tail C, or extension of each will reach backwards a distance of rather
more than half the distance between the orifice of such arm and that of the
next following; also that other corresponding induction passages, valves, and
stops will be provided.
Figures 2 and 3 represent the mode of adapting the kind of engines just
described for working expansively; Fig. 2 shews the side of the engine in
which the steam or other clastic fluid is made to act at high pressure; and
Fig. 3 shews that in which the same is made to act expansively. It will not
be necessary to repeat the description of the action of the elastic fluid on tho
high-pressure side of the engine, but merely to explain the position of the
parts as now represented.
It will be seen that in this arrangement the tail C on the high-pressure side
(Fig. 2) extends backwards nearly to the arm B, while that on the expansion
side (Fig. 3) reaches backwards only a little more than a semicircle from the
travelling piston L. The revolving arm B is supposed to have proceeded
from in front of the stop F, and to have just passed the stop F, at which time
the annular space or channel between these two stops is full of high-pressure
steam, and the expansion stop F2 (Fig. 3) is in its required position. The
expansion stops F and F are worked by a cam similar to that by which the
high-pressure stops F and F', are worked, and these cams must bear their
proper relation to each other, (that is to say,) the high-pressure can must be
arranged so that it will begin to raise and withdraw each high-pressure stop
from the steam channel as soon as the tail-C of the arm B passes that stop,
and that it may be quite out before the end of the revolving arm B reaches it.
With the parts in the respective positions stated it will be seen that no steam

page_text: can escape from, the annular space or channel between the stops F and F¹,
except through the orifice K (which leads into the expansion side of the
engine) until the end of the high-pressure tail C has passed the stop F¹, and
that the piston L on the expansion side (Fig. 3) has the pressure of the
expanding steam or other elastic fluid on it all that time. The expansion
piston L, and stops F and F³, must be so arranged that the piston shall have
passed the corresponding expansion stop, and that stop have returned to its
position to act as a stop before the revolving arm B on the high-pressure side
reaches such a position that the elastic fluid can pass out of the high-pressure
side through either of the orifices K or K', on either side of the ring. The
flange of the high-pressure side, in which the orifices K and K' are formed,
acts, or may be used as one of the flanges of the expansion side; and there
must be a second flange in order to complete the steam channel on both sides.
There may also be an expansion side on both sides of the high-pressure portion
of the engine.
From the foregoing explanation of the position of the parts and the course
of the fluid it will be evident that the engine will be impelled by the concurrent
actions the high-pressure steam on the arm B, as described in reference to
Fig. 1, and the expanding steam on the piston L. And this expansion
principle may be adapted to, engines in which two or more high-pressure
arms are employed by multiplying the mechanism so as to provide for the
succession of impulses on each arm with the corresponding succession of
expansive actions on each piston.
Fig. 4 shews an arrangement for obtaining the expansive action of the
steam when there is only one induction passage and valve. The valve E in
this case is worked out and in, so as to open and close the passage of steam by
the same means as that represented at Fig. 2, except that when the cam has
in its revolution arrived near the stop F', it acts upon the connecting rods so
as to draw in the valve E without at the same time working another valve, as
in the former case.
Fig. 5 shows the mode of applying the above-described arrangements to
engines with a travelling piston acted upon at the circumference of revolution
instead of a revolving arm acted upon, at, or near the centre thereof. In this
case the clastic fluid entering from the induction passage D acts on the
piston B within the channel and impels it forward in the direction of the arrow.
the stop F being in the position to act as an abuttal. As the piston B proceeds
the channel behind the stop is filled with high-pressure steam which escapes
through the orifice into the expansion side which is the same as that described
in reference to Fig. 4 and works a piston on that side by the mere expansion

page_text: of this steam until the tail C has passed the stop F. The stops on the
expansion side are the same as described under Fig. 3. The Figures above
described illustrate the first three heads of my Invention.
With reference to the fourth head I would remark that it will be understood
by taking Fig. 1, and substituting for the induction passages and valves, with
the mechanism for working the same, similar arrangements for admitting the
impelling fluid into the revolving arm at the centre of revolution to those used
in engines of the Barker's mill class, such as Craig's rotary engine, and also
in the recoil engines described in my former Patent before referred to. Thus,
the engine in its simplest form will consist of a revolving arm with an inlet
for the fluid at the centre of revolution with a tail or extension working in a
flanged ring (the said tail forming therewith a channel for the fluid,) combined
with stops or abuttals, as described under Fig. 1. Two or more revolving
arms, with corresponding tails and stops, may also be employed, as represented
in Fig. 6, berein-after described.
Then as to the use of the elastic fluid expansively, this will be understood
by taking Figures 2 and 3, and in like manner substituting the means of
admission for the elastic fluid to the arm at the centre of revolution instead of
at its outer end through the passages outside the ring A. In this case the
engine will consist of a revolving arm combined with the other parts just
mentioned together with the orifices for the passage of steam or other elastic
fluid into the expansion side of the engine, also with a travelling piston and
expansion stops with the mechanism for working them, as described under
Figures 3 and 4. And the expansion principle may likewise be adapted to
two or more high-pressure arms.
As to the fifth head, this improvement will be understood by merely sub-
stituting for the revolving arms last described, arms in which the outer ends
are closed towards the ring A, the stops being brought into the channel just
opposite the outlet for the impelling fluid, which is usual in such engines,
which fluid will thus be made to act directly on the stops.
The arrangements in other respects, both as to high pressure and expansive
action, are the same as last described.
Fig. 6, shews the position and arrangement of stops and tails in high-pres-
sure engines of the classes described under heads four and five, where two
arms are used, the one arm in the Figure shewing (for convenience) the one
kind of engine and the other the other kind. This will be obvious on refe-
rence to the Figure without any further description here. The dotted circle in
the centre is intended to represent a cross section of the induction pipe, and

page_text: the part a, b, shows the area of effective pressure in engines of the kind
described under the fourth head.
I would remark that the only points of difference between the arrangements
required for engines of the kind described under the fourth head and those
under the fifth are the two following:-First, in the engines described under
the fourth head, a diaphragm between the two arms, as represented in Fig. 6,
is required to furnish the area of effective pressure, while in those under the
the fifth head this diaphragm is not required, as the area of effective pressure
in them is at the circumference.
Second, that in engines described under the fourth head, the end of the
arms are open to the outer ring as represented, while in those under the fifth
head the arms are closed towards the outer ring, except so far as regards
their usual orifices."
I would also remark that the form of arm which I prefer for my impulse
rotary engines is shewn in its most simple form in Fig. 4, and may be readily
found in the following way:-Having fixed upon any size of engine, describe
a circle on any scale to represent the inner part of the circumforence of the
outer ring, then draw two diameters at right angles to one another, and from
the one of them at a, distance b, a, from the centre b, corresponding to tho
area of effective pressure, draw a line parallel to the other or second diameter,
then from the point c where this line meets the circumference of the circlo
drop a perpendicular upon the said second diameter cutting it at d. Then
the space between d and the circumference will represent a cross section of
the steam channel, and a, b, a, c, will give the form and proportions of the
sides of the arm; Fig. 6, shews the form which I prefer for engines described
under head four. It will be seen that its proportions are found in a manner
similar to that just described.
And with reference to the last head of my Invention, this will be understood
by taking Fig. 4, and substituting for the revolving arm therein, in which the
impelling fluid is caused to act on an area near the centre of revolution, a
revolving arm, the outer end of which is acted upon by the elastic fluid as in
the case of a travelling piston, the remaining portion of the arm being formed
so as to constitute an expansion chamber or reservoir for the expansion of the
fluid. This expansion chamber or reservoir in the arm may be varied in
form, my Invention under this head including other forms in which stops and
tails of the kind described are applied to impulse hollow arms provided with
a reservoir for steam or other elastic fluid intended to act expansively.
Having thus described the nature of the said Invention and in what manner

page_text: the same is to be performed, I hereby declare that what I claim as of my
Invention is,
First, the broad feature or principle of causing the impelling fluid while
admitted at the circumference to act directly and effectively on an area near
the centre of the circle of revolution, and in so arranging the parts of an
impulse rotary engine as to produce this effect; and for this purpose the use
of a hollow arm (or arms) with a tail or extension combined with a flanged
ring, induction passages, valves, and stops.as described.
Secondly, the arrangement described for working expansively the steam or
other elastic fluid used in engines of this description.
Thirdly, arrangements as to the high-pressure action of the impelling fluid,
and also the first described arrangements under head two, as to the expansive
action thereof when applied to impulse rotary engines, in which a solid piston
is made to travel within a steam channel as described.
Fourthly, the adaptation and application of the same arrangements (but
with the substitution of an inlet to the hollow revolving arm or arms at the
centre of revolution for the induction passages and valves), to the recoil
engines in my former Patent above referred to as described.
Fifthly, the same arrangements adapted and applied to engines on the
Barker's mill principle as described.
And, lastly, the use of elastic fluids expansively in impulse rotary engines by
means of a hollow arm or chamber opening into a steam channel at the
circumference, instead of by means of a separate expansion side of the engine
as described.
In witness whereof, I, the said Thomas Ivory, have hereunto set my
hand and seal, the Twenty-first day of September, in the year of our
Lord One thousand eight hundred and fifty-nine.
Witness,
JOHN C. CHRISTIE,
No. 4, Duncan Street,
THOMAS IVORY. (L.S.)
Newington, Edinburgh.