AN IMPROVED MODE OR MEANS FOR ACTUATING MOTIVE-POWER ENGINES, AND IMPROVEMENTS THE
Year: 1867

page_text: LETTERS PATENT to Andrew McCallum, of Greenock, in the County of
Renfrew, North Britain, for the Invention of "AN IMPROVED MODE OR
MEANS FOR ACTUATING MOTIVE-POWER ENGINES, AND IMPROVEMENTS IN THE
Sealed the 20th August 1867, and dated the 28th February 1867.
PROVISIONAL SPECIFICATION left by the said Andrew McCallum at
the Office of the Commissioners of Patents, with his Petition; on the
28th February 1867.
I, ANDREW MCCALLUM, of Greenock, in the County of Renfrew, North
Britain, do hereby declare the nature of the said Invention of "AN IMPROVED
MODE OR MEANS FOR ACTUATING MOTIVE-POWER ENGINES, AND IMPROVEMENTS IN
THE APPARATUS EMPLOYED THEREFOR," to be as follows, that is to say:
This Invention relates to the application of carbonic acid or other gas for
actuating motive-power engines, which engines themselves are constructed on
the general principles of steam engines, and in using these gases they are
compressed; expanded by heat, and after passing through the cylinders,
condensed so as to be continually used by being submitted to repeated

page_text: successions of compression, heating, and condensation. The motive-power
engine employed is provided with a pump or pumps for exhausting the gas or
gases from the condenser and forcing them into the chamber or chambers in
which the compressed gas or gases are held; the heating of the gas or gases
is effected by steam or otherwise, and the steam may be applied to the com-
pressed gas chamber or chambers in any convenient manner. It is preferred
that the chamber or chambers for holding the compressed gas should be
constructed of copper or other suitable material. In actuating motive-power
engines under this Invention the compressed and heated gas or gases are led
from the chamber or chambers containing them by suitable pipes to the slide
valves, by which they are distributed alternately to both sides of the pistons
working within the cylinders; on exhausting the gas or gases pass into the
condensing chamber or chambers which contain a large number of tubes, into
which the gas or gases as they are exhausted escape, the tubes being surrounded
with water the gas or gases on reaching the condenser immediately lose their
heat and diminish in volume to a corresponding extent. In the cold state the
pump or pumps before referred to transfer the gas or gases into the compressed
and heating chamber or chambers to be used over again, thus by repeated
successions of this treatment of the gas or gases a continuous source of motive
power is obtained. It is to be understood that before starting the engine to
work the gas or gases are compressed into the chamber, holding them up to a
certain point, and this pressure is maintained by the whole of the gas being
usefully employed, none of it being allowed to exhaust uselessly.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Andrew McCallum in the Great Seal Patent Office on the
26th August 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ANDREW
MCCALLUM, of Greenock, in the County of Renfrew, North Britain, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-eighth day of February, in the year of our
Lord One thousand eight hundred and sixty-seven, in the thirtieth year of
Her reign, did, for Herself,,Her heirs and successors, give and grant unto me,
the said Andrew McCallum, her special license that I, the said Andrew
McCallum, my executors, administrators, and assigns, or such others as I, the

page_text: .
said Andrew McCallum, my executors, administrators, or assigns, should
at any time agree with, and no others, from time to time and at all times
thereafter during the term therein expressed, should and lawfully might make,
иse, exercise, and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for "AN IMPROVED
MODE OR MEANS FOR ACTUATING MOTIVE-POWER ENGINE, AND IMPROVEMENTS IN
THE APPARATUS EMPLOYED THEREFOR," upon the condition (amongst others) that
I, the said Andrew McCallum, 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 Seal Patent Office within six calendar months
next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Andrew McCallum, do hereby declare
the nature of my said Invention, and in what manner the same is to. be
performed, to be particularly described and ascertained in and by the following.
statement, reference being had to the accompanying Drawings, and to the
letters and figures marked thereon, that is to say:-
My said Invention relates to the application of carbonic acid or other gas
for actuating motive-power engines, which engines themselves are constructed
on the general principles of steam engines, and in using these gases they aro
compressed, expanded by heat, and after passing through the cylinders, con-
densed or cooled so as to be continually used by being submitted to repeated suc-
cessions of compression, heating, expansion, and condensation. The motive power
engine employed is provided with a pump or pumps for exhausting the gas or
5 gases from the condenser and forcing them into the chamber or chambers in
which the compressed gas or gases are held. The heating of the gas or gases is
effected by steam or otherwise, and the steam may be applied to the compressed
gas chamber or chambers in any convenient manner. It is preferred that the
chamber or chambers for holding the compressed gas or gases should be
> constructed of copper or other suitable material. In actuating motive-power
engines under this Invention the compressed and heated gas or gases are led
from the chamber or chambers connecting them by suitable pipes to the slide
valves, by which they are distributed alternately to both sides of the pistons
working within the cylinders; on exhausting, the gas or gases pass into the
condensing chamber or chambers, which are made of copper or other suitable
material. It is to be understood that before starting the engine to work, the
gas or gases are compressed in the chamber, holding them up to a certain point,
and this pressure is maintained by the whole of the gas being usefully employed,

page_text: none of it being allowed to escape uselessly except what is unavoidable by
breakage.
:
It is to be understood that the gas used may be a pure gas or an admixture
of gases. The admission of gas into the cylinder may be cut off at any point
required by valves suitably worked by expansion gear, and I may here observe
that I prefer cutting off the gas at such portions of the stroke as will reduce
the pressure within the cylinder at the end of a stroke to any requisite
extent; it must be understood, however, that when the pressure at the end of
the stroke is much reduced, I prefer to use more than one cylinder, so that as
the pressure in one cylinder is diminishing, that in another shall be receiving
gas at the full pressure, thus maintaining the engine in a state of effecting work
at each instant as nearly constant in amount as practicable. I may further
add that in order to get the maximum effect out of an engine thus actuated,
I prefer to employ as many cylinders as possible, by which I am enabled to
diminish the period of admission to the smallest extent possible, and by adopting
a greater range of expansion within the cylinder I derive in a more perfect
degree the work due to the thermal energy in the gas or gases. In thus
employing a large number of cylinders they are arranged to act upon cranks
situated at such angles with each other, that as the pressure is diminishing in
one or more cylinders it shall be admitted at the higher pressure in a corre-
sponding set of cylinders. After the gas or gases have performed the work
due to their temperature and pressure they escape into the condenser, where
they are cooled and reduced in volume, after which they are withdrawn from
the condenser, again compressed by pumps, and returned in a compressed state
into the receiver. The vessel or receiver I prefer to be in communication with
the steam space of a boiler, or it may be either partly or wholly placed within a
boiler or other similar vessel, so that heat may be communicated to the gas or
gases contained within the vessel by either passing steam through or around or
through and around the vessel containing the gas, the circulation of the steam
through the vessel taking place by passing through steam-tight tubes or
passages, or by the vessel absorbing heat. The engine may be provided
with a suitable pump or pumps for the purpose of forcing in a supply of gas
sufficient to make up for the loss by leakage,
other
Having now set forth the main objects of my Invention, and the methods I
adopt to effect the same, I proceed to more particularly specify a system or
manner in or under which these objects may be carried out for practical use;
and to render this exposition more distinct, I refer to the elevations of a motive-
power engine constructed in accordance with my Invention, upon the annexed

page_text: Sheet of Drawings, of which Figure 1 is an end elevation, and Figure 2 a
front elevation of an inverted cylinder engine. In Figure 2 a part of the
main framing at the left-hand side of the Figure is not shown in order that
the parts of the engine which are hidden by it at the right-hand side may be
distinctly observed.
The cylinders A are fixed at the upper end of the main frames B, the
parallel parts of these frames, constituting guide bars, between which the cross
heads C travel as the piston rods to which they are attached are moved from
one end of the cylinders to the other; the reciprocating movement of thè
piston is communicated so as to rotate the crank shaft D by means of the
connecting rod E in the ordinary manner. The slide valves for distributing
the gas or gases to alternate sides of the piston are of the ordinary construction,
and contained within the valve casing F; they are actuated by the eccentrics
G, two of which are employed to drive each slide valve through the medium
of the links or quadrants II, the eccentric straps I being attached thereto in
the ordinary manner by pin joints, as shown at Figure 1, whilst the valve
spindles are coupled to a quadrant block embraced by the slot in the quadrants
or links H. The application of the gearing now described is to obtain what-
ever degree of expansion may be consistent with the work the engine is used
to effect, and the travel of the slide valves is regulated by means of the hand
lever K which is coupled to the quadrants H by the links L, so that in
correspondence with the position of the lever K on either side of a vertical line
the period of admission is regulated, and according to its inclination on either the
right-hand or left-hand side of that vertical line the engine is adjusted to run in
either a right or left hand direction. The lever K is moveable upon the way
shaft K', and capable of being adjusted by means of a reversing quadrant, or
by other means commonly employed, but which are not shown in my Drawings:
The receiver into which the gas is or the gases are compressed and heated, is
not shown in the Drawings, it is however desirable to keep it as near as
possible to the engines, to the valve casing of which it is coupled by means of
the pipe M. After the gas has passed through the engine it exhausts into the
condenser N through the pipe O, from which it is returned to the receiver by
the means now to be described. To the cross heads C links P are attached,
connecting thereto the levers Q, so that as the cross heads C are moved
upwards and downwards the levers are vibrated upon their gudgeons R,
carried in the bearings S. To the outer end of the levers Q, the connections
for working the several pumps employed are attached, innermost of which is
coupled the rod T for driving the trunk or hollow plunger U of the circulating

page_text: pump V;
this pump bas a pipe W proceeding from the lower clack box, through
which the water is circulated into the surface condenser, and which overflows by
the pipe X; the gas pumps Y and Z are double acting; their plunger rods a
are coupled to the ends of the levers Q by links b, connecting the pins e with
the cross head d. The larger pumps for drawing the gas from the condenser N
are in a line central with the middle line of each pair of pump beans Q, and
the smaller pumps Y, which are more particularly visible in the Drawings, are
attached to a projecting arm of the cross head d as shown at Figure 2. After
the gas is withdrawn from the condenser by the larger pump Z, it is com--
pressed into the barrel of the second pump Y, the pump being as herein-
before mentioned double acting; in escaping from the large pump the gas
passes to the opposite end of the small pump, alternate ends of the two pumps.
being united by means of passages and suitable valves to prevent the return of
the gas; that is to say, in the case of the gas or gases escaping from the
under side of the piston of the large pump they pass into the space on the
upper side of the plunger of the smaller pump, the reverse action taking place
when the gas passes from the upper side of the large pump. The pipes f and y
are those which connect the pumps together, and the pipes han 1 i are those
through which the gas is forced by the small pump Y back into the receiver..
Since I have not shown on my Drawings the vessel in which I heat the gas
or gases, I may here state that it may be constructed or arranged in several
ways, the vessel I have used being made of copper, and formed with a steam
space around it as well as having a coil of steam-tight pipe in its interior, into
which steam is also admitted.
Having now described and particularly ascertained the nature of my said
Invention, and' the manner of carrying the same into practical effect, I would
observe in conclusion that what I consider novel and original, and therefore
claim as the Invention secured to me by the herein-before in part recited
Letters Patent is,-
First, the actuating of motive-power engines by the application of com-
pression, heating, expansion, and cooling to a gas or a mixture of gases,
other than atmospheric air, which gas or mixture of gases are confined within
the engine and not allowed to escape except through such leakage as may be
unavoidable as herein-before described.
Second, I claim the use of steam for conveying heat from the furnace to the
gas when employed for actuating motive-power engines, substantially as herein-
before described.
Third, I claim actuating motive-power engines by means of a gas or gases

page_text: which are maintained in a vessel or receiver at constant pressure, constant
volume, and constant temperature, and admitted into the cylinder at that
pressure and temperature as nearly as practicable in contradistinction to the gas
being heated after leaving the receiver, or used at constant volume and
variable temperature as in other motive-power engines heretofore in use as
herein-before described.
In witness whereof, I, the said Andrew McCallum, have hereunto set
my hand and seal, this Twenty-fourth day of August, One thousand
eight hundred and sixty-seven.
ANDREW MCCALLUM. (L.B.)
Witness,
ST. JOHN VINCENT DAY, C.E.,
Patent Offices,
166, Buchanan Street,
Glasgow.