A CERTAIN IMPROVEMENT IN THE USE OF HEATED GASSES AND OF STEAM, WHETHER SUPERHEATED OR NOT, APPLICABLE TO ALL KINDS OF MOTIVE-POWER ENGINES, AND ENSURING GREAT ECONOMY OF FUEL, WITH OTHER ADVANTAGES
Year: 1873

page_text: LETTERS PATENT to William Edward Gedge, of No. 11, Wellington
Street, Strand, in the County of Middlesex, Patent Agent, for the
Invention of "A CERTAIN IMPROVEMENT IN THE USE OF HEATED GASSES
AND OF STEAM, WHETHER SUPERHEATED OR NOT, APPLICABLE TO ALL KINDS
OF MOTIVE-POWER ENGINES, AND ENSURING GREAT ECONOMY OF FUEL, WITH
OTHER ADVANTAGES."-A communication from abroad by Edmond
Fréville, of Thoiry (Seine and Oise), France.
Scaled the 6th January. 1874, and dated the 11th July 1873.
PROVISIONAL SPECIFICATION left by the said William Edward Gedge
at the Office of the Commissioners of Patents, with his Petition, on
the 11th July 1873.
-
I, WILLIAM EDWARD GEDGE, of No. 11, Wellington Street, Strand,
in the County of Middlesex, Patent Agent, do hereby declare the nature
of the said Invention for "A CERTAIN ImprovEMENT IN THE USE OF HEATED
GASSES, AND OF STEAM, WHETHER SUPERHEATED OR NOT, APPLICABLE TO ALL KINDS
OF MOTIVE-POWER ENGINES, AND ENSURING GREAT ECONOMY OF FUEL, WITH OTHER
A

page_text: ADVANTAGES," a communication to me from abroad by Edmond Fréville,
of Thoiry (Seine and Oise), France, to be as follows:-
Economy of fuel is now more than ever of vital importance in
industry. Notwithstanding the progress made since the Invention of
steam engines, and especially during the last ten years, the engines
now employed are still very far from giving the profitable use of fuel
which may
be realized. The cause of this is that in the system actually
adopted to utilize the motive power of steam interior condensations are
produced in the cylinders which are prejudicial to the profitable working
of the machines, and which, in addition to a moderately weak expansion,
further occasion the loss of the benefit which would result from a larger
expansion. The use of superheated steam, and of steam casings, the
constantly increasing employment of compound engines, combined with
high pressure and greater expansions, the increased velocity of the
piston stroke, and other arrangements have contributed in largely
reducing these interior condensations, or their relative importance,
and consequently the consumption of fuel. It may however be
estimated that the best engines set up under these conditions will
not burn much less than 2½ lbs. (1 kilog.) of good coal per hour,
and per horse power indicated I H P. It is only in some exceptionally
favorable and not yet perfectly certified cases that a less consumption
has been given.
In the state of perfection actually reached in engine making a
smaller consumption will only be reached by reducing or even entirely
doing away with the interior condensations in the cylinders. To attain
this end it is necessary that the steam should remain always in a
gaseous state, that is to say, always dry in the cylinder. Now the
expansion itself causing a partial condensation of steam it is necessary
to supply to the steam in expansion a sufficient quantity of heat to
prevent this condensation. Superheating is the means which naturally
presents itself, but hitherto it has only been sought to use the super-
heated steam by the ordinary method, consisting in the closing of
the communication with the generator after a certain introduction of
steam, and then leaving the steam to expand in one or several
cylinders.
In compound engines various systems have been tried for re-heating

page_text: given very satisfactory results, as may be easily ascertained. On the
other hand if it is desired to ascertain the superheating which should
be given to the steam in order that it may constantly remain dry during
its expansion, it will be found too high for practical use.
Steam at 5 absolute atmospheres expanding to 5 times its volume
should be superheated 180°, that is to say, that on its admission into
the cylinder its temperature would be above 330 centigrade. For an
expansion of ten the total temperature would exceed 400 degrees centi-
grade. As these temperatures have never been used it is difficult to
give exact figures, but it may be affirmed that no engine maker would
ever consent to set up an engine under such conditions. Nippings in
the cylinders, and slide valves, and burnt stuffing box glands would
soon render the engine unserviceable. A careful study of the question
has shown the Inventor that it is possible to avoid these inconveniences,
while reducing as much as may be desired, the interior condensations
in the cylinders, and for heated gasses the inconveniences arising from
their high temperature.
The principle applied by the Inventor to motive-power engines in
order to obtain this result is a well-known one. It is this,
" when
a fluid, gas or steam, expands in working its temperature lowers."
Let us suppose an engine at work, however much the initial tem-
perature of the fluid employed may be elevated, whether 200 or 300
degrees "centrigrade," or more, it is only necessary to suitably regulate
the quantity introduced into the cylinder at each moment, in order
that its temperature may also at each moment, and by the effect of its
expansion, be lowered as much as may be desired, and then be brought
back to the ordinary limits which permit a proper lubrication. The
orifices through which the admission of the very heated fluid is effected,
otherwise the re-heater, which however do not exclude the usual
admission through the ordinary ports, must necessarily be suitably
regulated for the production of this result, much smaller than the
ordinary ports, they will further be more or less open at each moment
of the stroke, according to the kind of motor employed, and the method
of working it.
It will be seen how this method is equally applied to gases as to
steam, whether employed in the ordinary conditions or at very high tem-
peratures. I shall therefore herein-after make no distinction between
gases and steam, as even fluids of different nature, such for instance as air
A 2

page_text: and steam from water may serve under this system to work a same engine.
In the most general case the new method presupposes therefore a fluid,
the admission of which will take place through one or several separate
orifices, or if desired through the ordinary orifices of the slide valves:
Also another fluid of a different or of a similar nature at a different and
generally higher pressure and temperature, and the admission of which
takes place through special orifices of somewhat small size, but sufficient
to permit a proper regulation of the quantity of fluid introduced. It is
the last mentioned [fluid that I call reheating fluid because it serves to
raise and maintain at the proper degree the temperature and pressure
within the cylinder. It may evidently be used alone which will be
more economical, but it may also be used concurrently with another
fluid, as will be the case when this new method is applied to existing
engines, or to analogous ones. For example, take an ordinary engine
with a single cylinder having two slide valves or one only as is more
generally the case (see Fig. 1 of the annexed Drawings). At the
extremities of the cylinder are placed two small slide valves, they may
also be combined in one. They will permit the introduction of the
reheating fluid into the cylinder during the whole or part of the stroke.
This reheating fluid is supplied by the same generator, on issuing from
which it passes into a superheating apparatus or through a special
generator, yielding the fluid at a higher pressure, and which may be
superheated or not. The important advantages obtained by this arrange-
ment will be at once evident. If the preceding engine. works in the
ordinary manner (and to permit it to do so it is only necessary to shut the
pipe M) its utility is considerably reduced by the interior condensations;
but if the pipe M is opened there may be introduced into the cylinder
during the expansion or the introduction a certain quantity of hot fluid,
the work of which will be added to that of the engine, and which will also
supply the steam with such quantity of heat as may be desired, sufficient
therefore to reduce the condensations, or to entirely do away with them,
as may be found preferable. The practical means of obtaining this
result consists therefore simply in the addition to the usual mechanism
of one or two small slide valves for the admission of the reheating fluid,
and in a special arrangement of pipes to bring this fluid to these slide
valves

page_text: reheating gas is operated. Now these parts may be reduced to simple
slides of small size, easily greased, or they may be shut by a valve, tap, or
other analogous mechanism. With the ordinary method the whole of
the slide valves would be exposed to the high temperature of the
reheater as well as the piston and the sides of the cylinder during the
period of admission and a part of the expansion.
.
When these defects in the slide valve are not feared there may be
employed for the admission of the reheater various modifications of the
actual ports, for instance an arrangement analogous to Meyer's system
of expansion. This Invention will be applied in the same way as in Fig. 1
to every kind of engine, whether ordinary or compound, whether with a
furnace or with one or two piston rods, and supplied or not with steam
casings, whether their axles be horizontal or inclined, and whether
oscillating, rotatory, or other engines. I need not therefore particularly
describe any system of engines; as all existing engines may be adapted
to the new method whether it serve simply as a useful accessory, as in
the preceding example, or that it alone be used to work the apparatus.
On reference to Fig. 1 it will be seen that it is only necessary to shut
the ordinary admission pipe B in order to obtain this result; but it will
be preferable in this case to modify the regulation of the ordinary slide
valve (which only serves now for the escapement). It should be
reduced to a solid slide bar, the evacuation taking place by the exterior
edges.
The organs of admission of the reheater, that is to say, the slide.
valves &c., will be placed in the most convenient position, as in Fig. 1
for example, or be applied against the cover itself; they may be worked
by the ordinary eccentrics, by a simple return motion, by special
eccentrics, or, if desired, by cams. The hot gas is brought to the
extremities of the cylinder through conduits made of cast iron or of
bronze, or through pipes C, C¹. It is indispensable that they be
protected against radiation by means of casings or coatings, bad con-
ductors of heat, such as coal dust covered with wood and felt. They
are ended by one or several orifices C, C¹, placed in the middle of the
cover on its sides C₁, C", or at the extremity of the cylinder and placed,
if desired, on the steam passage Fig. 2, and even in the orifices them-
selves C or c, c, c, c, Fig. 3.
The arrangements shown," Figures 2 and 3, are particularly advan--
i
:

page_text: '
tageous for the application of the method to existing engines with
direct introductions, or for the low-pressure cylinders of compound
engines.
For the starting it is well to reserve the means of sending directly to
the parts T ordinary fluid from the admission pipe B as by the small
dotted pipe N. The new method is therefore applicable to all the usual
arrangements of the ordinary mechanisms used in the various systems of
engines. What characterises it is in short, "the complete or partial
"admission of the motor fluid or fluids through relatively small orifices
"properly calculated, and permitting the regulating, so to say, at will of
"the quantity introduced into the cylinder at every moment of the
"throw or stroke."
The pressures of these fluids may be regulated in the generators;
their temperature may be raised at will in one or several superheaters.
The quantity introduced at each moment is dependent upon the section
and the opening of the orifices, and upon the difference of pressure
between the cylinder and the valve boxes, and this latter may be
modified at will, even in the case of a unique pressure at the generators
from the effect of the strangulation of the admission valve. By suitably
varying the various elements the pressure as well as the temperature of
the fluid contained in the cylinder at the different moments of the
throw or stroke may be regulated. It is precisely in this that consists
the essential difference between the new method and the existing one,
which leaves during the introduction a free communication between the
generator and the engine. It may therefore be termed the "system of
regulated introduction into the cylinder."
The exact dimensions of the orifices of introduction of the reheating
fluid cannot be given; they will depend upon the conditions of each
motor, and of its working. Experience will soon show what is desirable
in each particular case.
Reduced to its simplest expression, suppose it to be desired to limit
the application to improving the utility of engines in actual use, as in
the above-considered example (Fig. 1), the new method will permit
the diminishing of the losses due to the interior condensations by
reheating the steam during its expansion, and if desired during its
admission into the cylinder. The section of the orifices will then remain
comprised between 1 and 120, or thereabouts, of the actual dimensions.

page_text: In fact the fluid admitted through the ordinary orifices may itself be
superheated, and in the case of compound engines the reheater of the
main cylinder may be immediately supplied with steam from the boilers
at the ordinary state, or previously superheated. Thus this method may
be applied immediately to every kind of engine with or without con-
densation, marine or land engines, whether fixed or movable, and gas or
steam engines.
The economy which it ensures is exceedingly important. For instance,
for marine engines, whether screw or paddle, it will give from 10 to
15% at a high speed, and up to 50% at low speed of pistons, and large
expansions.
Hot gas engines have not hitherto given the good results anticipated
from them. With this new method their working will be greatly
improved, and their yield increased from 20 to 30%, all the arrange-
ments other than those of the admission remaining the same in every
part. This method will permit the use of high temperatures while
avoiding the inconveniences which have hitherto proved insurmountable.
I shall cite as example the gas engine in which the gas is dilated in
the cylinder by the combustion of lighting gas or of hydrocarbons.
According to this Invention the detonation will be produced in a
separate reservoir placed at the side or at each end of the cylinder, and
the heated gas will be introduced into the cylinder by means of one
of the above-described arrangements for giving the regulated intro-
duction.
The engine being at work under the simple effect of the expansion
the temperature in the cylinder may be lowered at will, and the
lubrication will become easy. In engines of this kind as hitherto
constructed the circuit of the water circulation around the cylinder
carries off and causes a loss of from 50 to 55% of the expended heat.
With this new system this loss will be greatly reduced and the ultimate
economy may easily reach from 30 to 40%. It may be said in short
that the difference between the two engines is that the one I have
immediately above described is no more like the first than Watt's
engine is like Newcomen's. Watt has separated the condenser from the
cylinder to lessen the interior condensations.
According to this Invention the hot air tank is separated from the
cylinder to lower the temperature in the cylinder by means of the

page_text: regulated introduction, which renders the lubrication easy and reduces
the loss of heat by the cooling water.
Further it will be understood how this new method lends itself with
the same arrangement and the same facility to the use of gasses heated
by other means; the combustion of expanding or detonating bodies
(such as powder and pyroxile) of oils, petroleums, or even of coal.
This Invention renders the compressed air engine practicable. The
power stored by the compressed air will be almost integrally restored
by reheating and afterwards utilizing it by means of the regulated
introduction. For this purpose a superheater is set between the air
reservoir and the engine, and there is thus obtained a convenient and
very. economical solution of the transmission of power to a great
distance; engines may also be constructed which will give the means of
solving the problem of the locomotion of vehicles on land, and also of
ordinary aerial or submarine navigation.
I have not set forth the process employed to obtain the pressure or
superheating of the moving fluids, it being a subject apart from this
new method. If they are gasses they will be compressed or heated by
known process; as to the steam it will be supplied from various kinds of
boilers, and be superheated when necessary by known processes or other
analogous ones.
t
On Figures 1, 2, and 3, of the accompanying Sheet of Drawing
S indicates the driving cylinder. There may be two slide valves for the
admission and the evacuation, or one alone, as assumed; A, ordinary
inlet ports; a, orifices of admission into the cylinder; E, escape into
the atmosphere or to the condenser; B, arrival of the driving fluid;
L, slide forming an additional apparatus for the introduction of the
reheating fluid which comes into M. This slide valve may be replaced
by two others, be applied directly on the cover (R, R, coming into O, O'),
or even be placed inside the piston; G or G¹, driving rod of the slide L.
This rod is operated by the ordinary eccentrics or by special circular or
curved eccentrics%3B C, C³, pipes surrounded by isolating matters;
O or 0³, O¹, inlet orifices of the reheater. They are simple as at O or
bifurcated into two, three, or four branches as at O¹, O¹, ending in a single,
round, or lengthened orifice, or by a greater number see C, C", Fig. 2,
and C¹, C³, or c, c, c, c, Fig. 3, circular or not. They are placed in the
middle of the cover eccentrically ending, for instance, near or in the

page_text: orifice itself, Figures 2 and 3. M, pipe establishing at will communica-
tion between the arrival pipes B and M.
By closing the arrival pipe M the engine works as an ordinary engine,
and by opening it this engine works according to the method of this
Invention, either with the ordinary fluid coming in at B or without this
latter by closing the inlet pipe B.
•
The arrangement shown, Figures 2 and 3, will be particularly advan-
tageous for the application of this method to ordinary engines, or even
to the great cylinder of "Woolf's" engines.
To sum up, this Invention consists in the various arrangements herein-
before described, for obtaining the admission of one or several motive
power fluids through orifices properly calculated and permitting as it
were the regulation at will of the pressure as well as the temperature of
the fluid in the cylinder at the different moments of the throw or
journey constituting the method of regulated introduction into the
cylinder.
<C
This method which permits the use of temperatures of 200, 300, or
400 degrees centigrade" and more without the usual inconveniences
ensures a considerable economy of fuel, and consequently is of very
great commercial and industrial importance.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Edward Gedge in the Great Seal Patent
Office on the 9th January 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
EDWARD GEDGE, of No. 11, Wellington Street, Strand, in the County of
Middlesex, Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eleventh day of July, in the year
of our Lord One thousand eight hundred and seventy-three, in the
thirty-seventh year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said William Edward Gedge,
Her special licence that I, the said William Edward Gedge, my
executors, administrators, and assigns, or such others as I, the said

page_text: William Edward Gedge, 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 "A CERTAIN IMPROVEMENT IN THE USE OF HEATED GASES AND
OF STEAM, WHETHER SUPERHEATED OR NOT, APPLICABLE TO ALL KINDS OF MOTIVE-
POWER ENGINES, AND ENSURING GREAT ECONONY OF FUEL WITH OTHER ADVAN-
TAGES," a communication to me from abroad by Edmond Fréville, of
Thoiry (Seine and Oise), France, upon the condition (amongst others)
that I, the said William Edward Gedge, my executors or administrators,
by an instrument in writing under my, or their, or one of their hands
and seals, 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 William Edward Gedge, do hereby
declare the nature of the said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained in 1
and by the following statement :-
2
Economy of fuel is now more than ever of vital importance in
industry. Notwithstanding the progress made since the Invention of
steam engines, and especially during the last ten years, the engines now
employed are still very far from giving the profitable use of fuel which
may be realized. The cause of this is that in the system actually adopted
to utilize the motive power of steam, interior condensations are produced
in the cylinders which are prejudicial to the profitable working of the
machines, and which in addition to a moderately weak expansion further
occasion the loss of the benefit which would result from a larger
expansion. The use of superheated steam and of steam casings, the
constantly increasing employment of compound engines combined with
high pressure and greater expansions, the increased velocity of the piston
stroke, and other arrangements, have contributed in largely reducing
these interior condensations or their relative importance, and conse- 3
quently the consumption of fuel. It may however be estimated that the
best engines set up under these conditions will not burn much less than
2½ lbs. (1 kilog.) of good coal per hour and per horse power, indicated.

page_text: I H P. It is only in some exceptionally favorably and not yet perfectly
certified cases that a less consumption has been given.
In the state of perfection actually reached in engine making a smaller
consumption will only be reached by reducing or even entirely doing
away with the interior condensations in the cylinders. To attain this
end it is necessary that the steam should remain always in a gaseous
state, that is to say, always dry in the cylinder. Now the expansion
itself causing a partial condensation of steam it is necessary to supply
to the steam in expansion a sufficient quantity of heat to prevent this
condensation. Superheating is the means which naturally presents
itself. But hitherto it has only been sought to use the superheated
steam by the ordinary method, consisting in the closing of the com-
munication with the generator after a certain introduction of steam, and
then leaving the steam to expand in one or several cylinders.
In compound engines various systems have been tried for reheating
the steam as it issues from the 1st cylinder, but none of them have given
very satisfactory results, as may be easily ascertained. On the other
hand, if it is desired to ascertain the superheating which should be given
to the steam in order that it may constantly remain dry during its
expansion, it will be found too high for practical use.
Steam at 5 absolute atmospheres, expanding to five times its volume,
should be superheated 180°, that is to say, that on its admission into the
cylinder its temperature would be above 330° "centigrade." For an
expansion of ten the total temperature would exceed 400 degrees "centi-
grade." As these temperatures have never been used, it is difficult to
give exact figures, but it may be affirmed that no engine maker would
ever consent to set up an engine under such conditions; nippings in
the cylinders and slide valves and burnt stuffing box glands would soon
render the engine unserviceable. A careful study of the question has
shown the Inventor that it is possible to avoid these inconveniences
while reducing as much as may be desired the interior condensations in
the cylinders, and for heated gasses the inconveniences arising from
their high temperature.
The principle applied by the Inventor to motive-power engines in
order to obtain this result is a well-known one. It is this: "When a
fluid, gas, or steam expands in working its temperature lowers." Let us.
suppose an engine at work. However much the initial temperature of

page_text: the fluid employed may be elevated, whether 200 or 300 degrees “ centi-
grade" or more, it is only necessary to suitably regulate the quantity
introduced into the cylinder at each moment in order that its tem-
perature may also at each moment and by the effect of its expansion be
lowered as much as may be desired, and then be brought back to the
ordinary limits, which permit a proper lubrication. The orifices through
which the admission of the very heated fluid is effected (otherwise the
reheater), which however do not exclude the usual admission through
the ordinary ports, must necessarily be suitably regulated for the pro-
duction of this result; much smaller than the ordinary ports, they will
further be more or less open at each moment of the stroke, according to
the kind of motor employed and the method of working it.
It will be seen how this method is equally applied to gasses as to
steam, whether employed in the ordinary conditions or at very high
temperatures. I shall therefore herein-after make no distinction 1
between gasses and steam, as even fluids of different nature, such, for
instance, as air and steam from water may serve under this system to
work a same engine. In the most general case the new method pre-
supposes therefore a fluid, the admission of which will take place
through one or several separate orifices, or if desired through the
ordinary orifices of the slide valves. Also another fluid of a different or
of a similar nature, at a different and generally higher pressure and
temperature, and the admission of which takes place through special
orifices of somewhat small size, but sufficient to permit a proper
régulation of the quantity of fluid introduced. It is the last-mentioned
fluid that I call reheating fluid, because it serves to raise and maintain
at the proper degree the temperature and pressure within the cylinder.
It may evidently be used alone, which will be more economical, but it
may also be used concurrently with another fluid, as will be the case
when this new method is applied to existing engines or to analogous ones.
For example, take an ordinary engine with a single cylinder, having
two slide valves, or one only, as is more generally the case (see Fig. 1 of
the annexed Sheet of Drawing). At the extremities of the cylinder are
placed two small slide valves, they may also be combined in one. They
will permit the introduction of the reheating fluid into the cylinder 3
during the whole or a part of of the stroke. This reheating fluid is supplied
by the same generator, on issuing from which it passes into a super-
heating apparatus or through a special generator yielding the fluid at a

page_text: higher pressure, and which may be superheated or not. The important
advantages obtained by this arrangement will be at once evident. If
the preceeding engine works in the ordinary manner (and to permit it to
do so it is only necessary to shut the pipe M). its utility. is considerably
reduced by the interior condensations; but if the pipe. M is opened there
may be introduced into the cylinder, during the expansion or the
introduction, a certain quantity of hot fluid, the work of which will be
added to that of the engine, and which will also supply the steam with
such quantity of heat as may be desired, sufficient therefore to reduce
the condensations or to entirely do away with them, as may be found
preferable. The practical means of obtaining this result consists there-
fore simply in the addition to the usual mechanism of one or two small
slide valves for the admission of the reheating fluid, and in a special
arrangement of pipes to bring this fluid to these slide valves.
The only practical inconveniences that this system may have, are in
the greasing or lubrication of the parts by which the admission of the
reheating gas is operated. Now these parts may be reduced to simple
slides of small size, easily greased, or they may be shut by a valve, tap,
or other analogous mechanism. With the ordinary method the whole
of the slide valves would be exposed to the high temperature of the
reheater as well as the piston, and the sides of the cylinder during the
period of admission and a part of the expansion. When these defects
in the slide valve are not feared, there may be employed for the
admission of the reheater various modifications of the actual ports, for
instance, an arrangement analogous to "Meyer's" system of expansion.
This method will be applied in the same way as in Fig. 1. to every kind'
of engine, whether ordinary or compound, whether with a furnace or
with one or two piston rods, and supplied or not with steam casings,
whether their axles be horizontal or inclined, and whether oscil-
lating, rotatory, or other engines. I need not therefore particularly.
describe any system of engines, as all existing engines may be adapted
to the new method, whether it serve simply as a useful. accessory, as
in the preceding example, or that it alone be used to work the
apparatus..
'
On reference to Figure 1 it will be seen that it is only necessary to
shut the ordinary admission pipe B in order to obtain this result. But
it will be preferable in this case to modify the regulation of the
ordinary slide valve (which, only serves now for the escapement). It:

page_text: should be reduced to a solid slide bar, the evacuation taking place by
the exterior edges.
The organs of admission of the reheater, that is to say, the slide bars,
valves, &c., will be placed in the most convenient position, as in Fig. 1,
for example, or be applied against the cover itself. They may be
worked by the ordinary eccentrics, by a simple return motion, by
special eccentrics, or if desired by cams. The hot gas is brought to the
extremities of the cylinder through conduits made of cast iron, or of
bronze, or through pipes, C, C¹. It is indispensable that they be
protected against radiation by means of casings or coatings, bad
conductors of heat, such as coal dust, covered with wood and felt.
They are ended by one or several orifices c, c', placed in the middle of the
cover on its sides c¹, c", or at the extremity of the cylinder, and placed
if desired on the steam passage, Fig. 2, and even in the orifices
themselves, c¹ or c, c, c, c, Fig. 3.
The arrangements shown, Figures 2 and 3, are particularly advan-
tageous for the application of the method to existing engines with
direct introductions, or for the low-pressure cylinders of compound
engines. For the starting it is well to reserve the means of sending
directly to the parts L ordinary fluid from the admission pipe B as by
the small dotted pipe N. The new method is therefore applicable to
all the usual arrangements of the ordinary mechanisms used in the
various systems of engines. What characterizes it is, in short, “the
"complete or partial admission of the motor fluid or fluids through
"relatively small orifices properly calculated, and permitting the regu-
"lating, so to say, at will of the quantity introduced into the cylinder at
every
moment of the throw or stroke."
66
The pressures of these fluids may be regulated in the generators,
their temperature may be raised at will in one or several superheaters;
the quantity introduced at each moment is dependent upon the section
and the opening of the orifices, and upon the difference of pressure
between the cylinder and the valve boxes, and this latter may be
modified at will, even in the case of a unique pressure at the generators
from the effect of the strangulation of the admission valve. By
suitably varying the various elements the pressure as well as the
temperature of the fluid contained in the cylinder at the different
moments of the throw or stroke may be regulated. It is precisely in

page_text: this that consists the essential difference between the new method and
the existing one, which leaves during the introduction a free com-
munication between the generator and the engine. It may therefore
be termed the "system of regulated introduction into the cylinder."
5 The exact dimensions of the orifices of introduction of the reheating
fluid cannot be given. They will depend upon the conditions of each
motor, and of its working. Experience will soon show what is desirable
in each particular case.
Reduced to its simplest expression, suppose it to be desired to limit
the application to improving the utility of engines in actual use, as in
the above considered example (Fig. 1), the new method will permit
the diminishing of the losses due to the interior condensations by
reheating the steam during its expansion, and if desired during its
admission into the cylinder. The section of the orifices will then
remain comprised between 1 and 2, or thereabouts, of the actual
dimensions; in fact the fluid admitted through the ordinary orifices
may itself be superheated, and in the case of compound engines the
reheater of the main cylinder may be immediately supplied with steam
from the boilers at the ordinary state, or previously superheated. Thus
this method may be applied immediately to every kind of engine, with
or without condensation, marine or land engines, whether fixed or
moveable, and gas or steam engines.
The economy which it ensures is exceedingly important. For
instance, for marine engines, whether screw or paddle, it will give from
10 to 15% at a high speed, and up to 50% at low speed, of pistons and
large expansions.
Hot gas engines have not hitherto given the good results anticipated
from them. With this new method their working will be greatly
improved and their yield increased from 20 to 30%, all the arrangements
other than those of the admission remaining the same in every part.
This method will permit the use of high temperatures while avoiding
the inconveniences which have hitherto proved insurmountable. I shall
cite as example the gas engine, in which the gas is dilated in the
cylinder by the combustion of lighting gas, or of hydrocarbons.
According to this Invention the detonation will be produced in a
separate reservoir placed at the side or at each end of the cylinder, and

page_text: the heated gas will be introduced into the cylinder by means of
one of the above described arrangements for giving the regulated
introduction.
The engine being at work under the simple effect of the expansion
the temperature in the cylinder may be lowered at will, and the lubri-
cation will become easy. In engines of this kind as hitherto constructed
the circuit of the water circulating around the cylinder carries off and
causes a loss of from 50 to 55% of the expended heat. With this new
system this loss will be greatly reduced, and the ultimate economy may
easily reach from 30 to 40%. It may be said in short that the difference
between the two engines is that the one I have immediately above
described is no more like the first than "Watt's" engine is like "New-
comen's." "Watt" has separated the condenser from the cylinder to
lessen the interior condensations.
According to this Invention the hot-air tank is separated from thō
cylinder to lower the temperature in the cylinder by means of the regu-
lated introduction, which renders the lubrication casy and reduces the
loss of heat by the cooling water.
Further, it will be understood how this new method lends itself with
the same arrangement and the same facility to the use of gasses heated
by other means, the combustion of expanding or detonating bodies (such
as powder and pyroxile) of oils, petroleums, or even of coal.
This Invention renders the compressed air engine practicable. The
power stored by the compressed air will be almost integrally restored by
reheating, and afterwards utilizing it by means of the regulated intro-
duction. For this purpose a superheater is set between the air reservoir
and the engine, and there is thus obtained a convenient and very
economical solution of the transmission of power to a great distance.
Engines may also be constructed which will give the means of solving
the problem of the locomotion of vehicles on land, and also of ordinary
aerial or submarine navigation.
I have not set forth the process employed to obtain the pressure or
superheating of the moving fluids, it being a subject apart from this
new method. If they are gasses they will be compressed or heated by any
known process. As to the steam it will be supplied from various kinds

page_text: of boilers, and be superheated when necessary by known processes or
other analogous ones.
On Figures 1, 2, and 3 of the accompanying Sheet of Drawing
S indicates the driving cylinder. There may be two slide valves for the
admission and the évacuation, or one alone, as assumed. A, ordinary
inlet ports; a, orifices of admission into the cylinder; E, escape into the
atmosphere or to the condenser; B, arrival of the driving fluid; L, slide
forming an additional apparatus for the introduction of the reheating
fluid which comes into M. The slide valve may be replaced by two
others, be applied directly on the cover (R, R, coming into O, O¹), or
even placed inside the piston. G or G¹, driving rod of the slide L.
This rod is operated by the ordinary eccentrics or by special circular or
curved eccentrics. C, C¹, pipes surrounded by isolating matters; O or
0¹, 0¹, inlet orifices of the reheater. They are simple as at O or bifur-
cated into two, three, or four branches as at O¹, O¹, ending in a single
round or lengthened orifice or by a greater number, see C, C", Fig. 2,
and C¹, C¹, or c, c, c, c, Fig. 3, circular or not. They are placed in the
middle of the cover eccentrically, ending for instance near or in the
orifice itself, Figures 2 and 3. N, pipe establishing at will communi-
cation between the arrival pipes B and M.
By closing the arrival pipe M the engine works as an ordinary engine,
and by opening it the engine works according to the method of this
Invention, either with the ordinary fluid coming in at B or without this
latter by closing the inlet pipe B.
The arrangement shown Figures 2 and 3 will be particularly advan-
tageous for the application of this method to ordinary engines or even to
the great cylinder of "Woolf's" engines.
To sum up, this Invention consists in the various arrangements herein.
before described for obtaining the admission of one or several motive
power fluids through orifices properly calculated and permitting as it
were the regulation at will of the pressure as well as the temperature of
the fluid in the cylinder at the different moments of the throw or
journey, constituting the method of regulated introduction into the
cylinder.
This method which permits the use of temperatures of 200, 300, or
400 degrees "centigrade" and more without the usual inconveniences

page_text: ensures a considerable economy of fuel, and consequently is of very
great commercial and industrial importance.
In witness whereof, I, the said William Edward Gedge, have here-
unto set my hand and seal, this Ninth day of January, in the
year of our Lord One thousand eight hundred and seventy-four.