IMPROVEMENTS IN STEAM ENGINES AND BOILERS, AND IN THE APPARATUS CONNECTED THEREWITH
Year: 1860

page_text: LETTERS PATENT to James Howden, of Glasgow, in the County of Lanark,
Engineer, for the Invention of "IMPROVEMENTS IN STEAM ENGINES AND
BOILERS, AND IN THE APPARATUS CONNECTED THEREWITH,"
Sealed the 17th May 1861, and dated the 21st November 1860.
PROVISIONAL SPECIFICATION left by the said James Howden at the
Office of the Commissioners of Patents, with his Petition, on the
21st November 1860.
I, JAMES HOWDEN, of Glasgow, in the County of Lanark, Engineer, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN
STEAM ENGINES AND BOILERS, AND IN THE APPARATUS CONNECTED THEREWITH," to
be as follows, that is to say:-
This Invention relates to various improvements in the arrangement &
working of steam engines & boilers.
One improvement in double-cylinder expansive engines consists in
placing two smaller cylinders which receive steam direct from the boiler
against the end of a larger one receiving steam from the two smaller
ones. The piston rod of the larger cylinder passes through a stuffing
box between the two smaller cylinders. The piston rods of the smaller
cylinders passing through their outer ends are attached to the piston
rod slide block of the larger cylinder by a cross piece and rods, allowing
free space for the connecting rod working between the cylinders. The

page_text: piston rod guides may either be on the sides of the small cylinders or
otherwise. This arrangemect of engine may be conveniently modified by
having two piston rods from the larger cylinder, so as to allow of the
inner end of the connecting rod coming closer to its cover.
Another improvement in double-cylinder expansive engines having
two smaller cylinders on one end of a larger cylinder, the piston rods of
the smaller cylinders joining directly with the piston of the larger one,
consists in having a trunk for the admission of the connecting rod from
the larger piston working through a stuffing box between the two
smaller cylinders. It is preferred to have this trunk of a flat or elliptical
shape, so as to allow a small space between the two cylinders, but
sufficient for the motion of the connecting rod lengthways. In working
steam of very high pressure, the engines previously described may have
four smaller cylinders on the end of a larger one, two of the four being
smaller than the other two. Steam of the highest pressure is admitted
first into the smallest pair, and after doing its work therein expands
through suitable valves into the next pair, and still further from them
into the largest or low-pressure cylinder.
Another arrangement of engine for steam of very high pressure
consists in having three cylinders of different sizes in working connec
tion with a lever or levers, two of the cylinders being on one side of the
fulcrum, and one on the other. The steam is first admitted by a valve
into the outer or smallest cylinder, and after doing its work therein it
passes into the second or middle cylinder, and from thence to the third
or largest cylinder. The connecting rod may be taken from either side
of the lever.
In another modification of engine, according to this Invention, two
low-pressure cylinders of equal size receive steam from two high-
pressure cylinders, also of equal size. These four cylinders are arranged
alongside with their axes parallel to each other, and in such a manner
that straight lines drawn from centre to centre of the cylinders would
form a parallelogram, the cylinders at the opposite angles being of the
same size. The piston rods from each cylinder are united at the end
farthest from the crank to a cross peice, upon which also is the working
joint of the connecting rod. The connecting rod passes through a space
left between the cylinders to the crank.
Another improvements according to this Invention consists in a novel
arrangement of slide valve for the admission and emission of steam to
and from one or more cylinders, by which the friction from pressure is
altogether or nearly relieved from its working surface. This is obtained
by having a plate fitted on the back of the valve of the same or nearly
the same area as the steam face of the valve. This plate has a part pro-
jecting on the side next to the valve, of the same shape and size on

page_text: its outside as the body of the valve itself, the whole being free to move
in the opposite direction from the valve and against the back of the
steam casing on which the plate works. Between the projecting part on
the plate and the body of the valve (when the face of the plate is
against the back of the casing and the valve against the face of the
cylinder), there is a slightly tapered groove or recess all round, into
which a ring or band of india-rubber or other suitable elastic material
is shrunk or fitted, so as to make a steam-tight joint between the plate
and the valve, the pressure of the steam on the outside assisting in
making the joint tight. The pressure of the steam by this means may
be entirely relieved from the working faces, or as much may be put on
the valve and back plate as to ensure their being always kept steam-
tight against their respective faces. Instead of having the joint made
with a ring or band fitted into a groove between the back plate and
valve, a flat band of india-rubber or other elastic material may be
fastened steam-tight, partly on the valve and partly on the plate, the
elasticity of the material allowing the pressure of the steam on the
slightly projecting faces that are left for that purpose to keep the valve
and plate steam-tight against their respective faces. This elastic band
peice fastened on the valve and back plate may also be conveniently
made of thin metal in a
form.
These valves are well adapted
for working two cylinders in combined engines, having their steam.
ports in one casing and parallel to each other, the steam being passed
in this case from one cylinder to another through suitable ports in the
valve, the whole being of the nature of a double valve back to back,
but jointed steam-tight, as before described. When there are passages
through the valves, such as in the case last described, or for exhaust
or steam ports, a ring or band similar to those described may be used
for the same purpose in the inside joint between the two parts of the
valve.
An improvement in "cut-off" valves consists in having a cylindrical
valve in the steam ports of the cylinder working in conjunction with the
slide valve. These "cut-off" valves are preferred to be put right across
from side to side of the steam ports and turned upon their axes by the
motion of the slide valve gear, or by a cam, or other means; the con-
necting gear being capable of easy adjustment to any amount of "cut-
off."
Another improvement in steam engines according to this Invention
consists in utilizing a great proportion of the sensible and latent heat
discharged from the engine with the exhaust steam, and also providing
for a simple means of condensation. This is effected by exhausting

page_text: the steam from one or more cylinders into a surface condenser,
where its condensation is effected by forcing or drawing air through
or among the tubes, according as the exhaust steam is in
contact with the inside or outside of the tubes. The air being
heated in so passing through or amongst the tubes is forced or drawn
through suitable passages to the furnace or furnaces of the boiler or
boilers, supplying the whole or part of the air required for the com-
bustion of the fuel; the furnaces and ash-pits being arranged to admit
of this being properly carried out. The efficiency of this system of
condensation is greatly increased by sprinkling water on the surface of
the tubes with which the air is in contact, for the purpose of causing an
evaporation on the opposite side of the tubes to that with which the
exhaust steam is in contact. This evaporation being increased by the
air passing through as aforesaid causes a strong refrigerating action to
take place, and maintains a good vacuum within the condenser. The
vapour arising from this evaporation is carried along with the air to the
furnace, increasing the effective elements of combustion. It is pre-
ferred to have the water dispersed with the air among the tubes in the
form of fine spray, but any convenient method may be used to keep the
surface of the tubes continually moist. This system may be used for
condensation without using the heated air and vapour for the boiler
furnaces, and instead of using a surface condenser the same means may
be employed in cooling the water pumped from the condenser of an
engine through a refrigerator to be used for reinjection.
Another portion of improvements consists in fixing the tubes of
surface condensers or refrigerators in the tube plates by packing (in the
manner of a stuffing box) a recess round the tube with cord, loose hemp,
or other fibrous material, with which white or red lead may be used.
When the exhaust steam is admitted to the inside surfaces of the tubes
in a surface condenser the tubes may be fixed in the tube plate at one
end with rust or other material having similar properties, and at the
other by any elastic packing, or they may be rusted at both ends.
An improvement in refrigerators for cooling the water from the con-
denser for reinjection in marine engines consists in having a cistern in
free connection with the cold well or part of the refrigerator into which
the water is discharged after passing through the tubes. It is preferred
to have this cistern at least twice as large as the condenser, and it may
be formed in the keelsons or engine seats, or in the bed plate casting of
the engine, or it may be with suitable connections in any part of the
ship.
Another improvement in refrigerators is in making the division plates
which divide the cooling currents so as to make them run in opposite

page_text: direction to the water to be cooled, with a strip of leather or other such
pliable material on each side so as to make a joint with the sides of the
vessel, the
pressure of the cooling water in its passage assisting in keep-
ing these leather strips tight against the sides of the vessel. Refrige-
rators with these improvements may be used partly as a surface con-
denser in condensing steam from salt water for the purpose of supplying
the waste of fresh water from the boilers of marine engines.
According to this Invention in an improved method of regulating the
speed of steam engines the amount of steam admitted to the engine is
proportioned to the amount of resistance to be overcome. This is con-
veniently effected by having that part of the shaft from which the power
is taken separate from the engine shaft and driven by a clutch or disc
having projections on its face or edge to catch projections on a similar
clutch or disc on the crank shaft. Between each of these projections
a spring of metal, india-rubber, or other elastic material is placed, so
that the driving power is transmitted through the springs. When the
resistance is increased the compression on the springs is also increased,
and the catches on the discs approach nearer to each other, thereby
giving motion to a lever in connection with the "throttle" and "cut-
off" valves, admitting a greater amount of steam to the cylinder or
cylinders. When the resistance is lessened the distance between the
catches is increased, and the contrary motion being thereby given to
the lever a smaller amount of steam is admitted to the cylinder or
cylinders.
In one modification of an improved boiler according to this Invention,
a series of rows of tubes are placed vertically on each side of the fire
grate; these tubes are in free connection with flat hemispherical or other
conveniently shaped chambers at both ends, the upper chambers having
a water and steam space; between these chambers and directly over
the fire grate are one, two, or more small horizontal cylindrical vessels
(according to the width of the grate) in connection with and having.
the same water level as the upper chambers. The steam spaces and
cylindrical vessels are connected to one or more steam receivers from
which the steam is supplied to the engine. In this boiler the fire gases
first act on the cylindrical vessels over the grate, they then pass through
among the upper ends of the tubes on either side, then descending cross
among the lower ends of the tubes, and from thence ascending by a flue
or flues pass round the steam receiver or receivers before entering the
chimney. Instead of vertical tubes they may be conveniently arranged
horizontally and in free connection with water chambers at both ends,
the small horizontal vessels being not only over the fire grate, as in the
arrangement previously described, but extending also over the tubes and

page_text: connected with their chambers. The fire gases circulate as in the
arrangemant previously described. The diameter of the cylindrical
vessels in these boilers may range from 12 to 24 inches, and the tubes
from 2 to 6 inches, though other sizes may be used. These arrangements
may be modified in various ways, such as having the fire grate placed so
that the fire gases may cross among the lower ends or series of the tubes,
and recross at the upper ends or series, part of the fire gases acting on
the vessels above as before described. They may also be without vessels
over the fire grate, or the tubes may be at one side of the fire grate only.
In these modifications where the fire gases descend the current of the
gases runs in a contrary direction to that of the feed water.
In another modification of these boilers, instead of having a com-
bination of cylindrical vessels with small tubes and chambers as
described, the horizontal cylindrical vessels are retained over the fire
grate, and alongside them on each side and on the same level are other
vessels of the same size having one or more series underneath, the
under side of the higher vessels being connected through their length
in one or more places with the upper side of the lower ones. The fire
gases first pass backwards underneath the vessels immediately over the
grate and parting at the back return underneath the vessels on each
side, then again backwards and forwards underneath those series below,
afterwards they ascend and circulate round the steam receiver or
receivers before passing to the chimney. Instead of arranging these
vessels in rectangular form round the fire grate they may also be con-
veniently arranged over and around in a circular or polygonal form,
the fire gases passing in a similar manner to that last described. These
cylindrical vessels, especially the lower ones, may have flues or tubes
through them to increase the surface acted upon by the fire gases.
In another modification of these boilers, composed of a number of
cylindrical vessels of the same or nearly the same size, the fire grate is
placed underneath one, two, or more horizontal vessels, below each of
these are one or more series of similar vessels, but shorter by the length
of the furnace, the under ones being connected with those immediately
above them as before described. The fire gases pass first underneath
the upper course of vessels and then underneath the under ones, a
suitable space being kept between the back of the furnace and the ends
of the lower vessels for the gases to pass on their course downwards.
This arrangement may have the furnace underneath the lower course
of vessels, and the gases pass first backwards under the lower course,
then return underneath the second course above, then again backwards
under the next course above that, returning still higher round the steam
receivers before passing to the chimney. When the vessels are made

page_text: with flues or tubes through them the fire gases may pass underneath
the vessels and return through their flues or tubes, or they may pass
underneath the vessels and through them at the same time, or through
one series and underneath the series above at the same time; and it is
to be understood that in all the other arrangements of boilers previously
described these cylindrical vessels may have flues or tubes through them,
the fire gases passing through in a similar manner.
In an improved cylindrical boiler according to this Invention suitable
for steam not exceeding 70 or 80 lbs. pressure per square inch, the
furnace is underneath the boiler, and the whole under half of the boiler
is exposed to the action of the fire gases, which after passing underneath
to the back end, return through one, two, or more flues or tubes in the
lower part of the boiler to the front, they then pass backwards through
a higher set of flues or tubes, after which they may either pass round
a steam receiver (preferred to be horizontal) above the boiler, or direct
to the chimney, or the fire gases instead of returning through one series
and again passing backwards through a higher series of flues or tubes,
may return to the front through both series at once, and then along the
top of the boiler and round the steam receiver or receivers to the chimney.
When two boilers of this description are placed together only one steam
receiver may be used for both.
These various modifications of boilers, having the whole or nearly the
whole of their surface exposed to the action of the fire gases, are sur-
rounded with a casing of brick and iron containing the necessary
divisions for the currents of the fire gases as described.
In another improvement comprehended in this Invention the greater
portion of the heat contained in the fire gases after leaving the boiler is
recovered and made available in promoting the combustion of the fuel
in the furnaces. This is effected by passing the fire gases in one or more
courses through or among a set of tubes conveniently arranged at the
under part of the chimney. A current of air (preferred to be running in
the opposite direction to the fire gases) is forced or drawn through or
among these tubes on the opposite side to that with which the fire gases
are in contact. Water is dispersed among the tubes as in the condenser
described in this Specification, causing an evaporation and refrigerating
action; the air and vapour carrying off the heat of the fire gases to the
furnace by suitable passages.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-first day of November, in the year of
our Lord One thousand eight hundred and sixty, in the twenty-fourth
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said James Howden, Her special licence that I, the
said James Howden, my executors, administrators, and assigns, or such
others as I, the said James Howden, 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 STEAM ENGINES AND
BOILERS, AND IN THE APPARATUS CONNECTED THEREWITH," upon the condition
(amongst others) that I, the said James Howden, 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 James Howden, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the
following statement in writing, reference being had to the accompany-
ing Drawings, and to the letters and figures marked thereon, that is
to say:-
My said Invention relates to various improvements in the arrange-
ment and working of steam engines and boilers; and in particularly
describing my said Invention, I shall refer, as I proceed, to the three
accompanying Sheets of Drawings, in which the same reference letters
mark the same or like parts in all the figures in which they occur.
One improvement in double-cylinder engines according to this Inven-
tion, consists in placing two smaller cylinders, which receive steam
direct from the boiler against the end of a larger one receiving steam
from the two smaller ones. The piston rod of the larger cylinder passes
through a stuffing box between the two smaller cylinders. The piston
rods of the two smaller cylinders passing through their outer ends are
attached to the piston rod slide block of the larger cylinder by a cross
piece and rods, allowing free space for the connecting rod working
between the cylinders.
In Sheet 1 of the accompanying Drawings, Figure 1 is an elevation,
and Figure 2 an inverted plan of the arrangement of engine described.

page_text: The two high-pressure cylinders A, A, are placed on the end of the
larger or low-pressure cylinder B. The two piston rods a, a, of the
high-pressure cylinders and the piston rod 6 of the low-pressure cylinder
being connected at the slide block by means of the cross pieces c, c;
the connecting rod C instead of working in the line of centres of the
high-pressure cylinders, may, with a slight modification of the cross
pieces and rods, be made to work at right angles thereto; this arrange-
ment of engine may also have two piston rods from the low-pressure
cylinder.
Another improvement in double-cylinder expansive engines according
to this Invention, having two smaller cylinders on one end of a larger
cylinder, the piston rods of the smaller cylinders joining directly with
the piston of the larger one, consists in having a trunk from the larger
piston working through a stuffing box between the two smaller cylinders.
It is preferred to have this trunk of a flat or elliptical shape, so as to
allow a small space between the two cylinders, but sufficient for the
motion of the connecting rod lengthways.
In Sheet 1 of the Drawings, Figure 3 is a sectional elevation, and
Figure 4 an inverted plan of this arrangement of engine, where the two
piston rods a, a, of the high-pressure cylinders A, A, are connected
to the piston D of the low-pressure cylinder B, the connecting rod C
working through the elongated trunk E.
Another arrangement of engine for steam of very high pressure
consists in having three cylinders of different sizes, in working con-
nection with a lever or levers, two of the cylinders being on one side
of the fulcrum and one on the other. The steam is first admitted by a
valve into the outer or smallest cylinder, and after doing its work therein,
it passes into the second or middle cylinder, and from thence by suitable
valves to the third or largest cylinder. The connecting rod may be
taken from either side of the lever.
the same.
One modification of this arrangement of engine is shown in Sheet 1
of the Drawings, Figure 5 being an elevation, and Figure 6 a plan of
A is the smallest cylinder, which receives steam of the
highest pressure; A is the second cylinder receiving steam from A';
and B is the third cylinder receiving steam from the second cylinder A.
The piston rods a', a, of the first and second cylinders are connected
to the lever or levers by the links d, d. Intead of connecting the
piston rods a', a, separately to the lever or levers they may be con-
nected together by a cross piece, and the cross piece to the lever or
levers, as shown by the dotted lines.
In another modification of engine, according to this Invention (shown
in Figures 7 and 8, Sheet 1 of the Drawings), two low-pressure cylinders

page_text: B, B, of equal size receive steam from two high-pressure cylinders A, A,
also of equal size; these four cylinders are arranged alongside with their
axes parallel to each other, in such a manner that straight lines drawn
from centre to centre would form a parallelogram, the cylinders at the
opposite angles being of the same size. The piston rods a, a, b, b, are
connected to one cross piece F, upon which also is the working joint
of the connecting rod. The connecting rod passes through a space left
between the cylinders to the crank.
In this last, and in the first and second arrangements of engines
described, the steam is first admitted to the smaller cylinders marked A,
by suitable valves, and after doing work therein, passes by the same
or other valves to the larger cylinders marked B, from which it may
pass to the condenser or be used in some other manner.
Another improvement in steam engines according to this Invention
consists in a novel arrangement of slide valve for the admission and
emission of steam to and from one or more cylinders, in which the
friction from pressure is altogether or nearly releived from its working
surface. This is obtained by having a plate or ring fitted on the back
of the valve of the same or nearly the same area as the steam face of
the valve; this plate or ring has a part projecting on the side next to
the valve, of the same shape and size on its outside as the body of the
valve itself, the whole being free to move nearer to or further from the
valve face; this plate or ring, which is carried by the valve, works
against the back of the casing or against a fixed plate in the inside of
the casing. Between the projecting part on the plate or ring and the
body of the valve (when the face of the plate or ring is against the
back of the casing, and the valve against the face of the cylinder), there
is a slightly tapered groove or recess all round, into which a ring or
band of india-rubber or other suitable elastic material is shrunk or fitted
so as to make a steam-tight joint between the plate or ring and the
valve, the pressure of the steam on the outside assisting in making the
joint tight. The pressure of the steam by this means may be entirely
eleived from the working faces, or as much may be put on the valve
and back plate as ensure their being always kept steam-tight against
their respective faces.
Figure 9, Sheet 2 of the accompanying Drawings, is a vertical section
of this arrangement of valve; G is the valve with its back plate or ring è
against the inside of the casing, the india-rubber ring or band f fitting
tightly between the plate or ring e and the valve G. Figure 10 shows
this method of releiving the pressure from the working faces of slide
valves, as applied to the valves of a pair of inverted cylinder engines,
where cut-off valves are also used. The back plates e, e, work

page_text: against the fixed plate g in the casing; Figure 11 shows this method
with a flat band of india-rubber or other suitable material. Instead of
using india-rubber,
a ring of thin metal in a U-form may be used
for the same purpose, it being partly fixed on the back plate and partly
on the valve; Figure 12 shows this modification. The steam by these
arrangements is prevented from pressing on the back of the valve, but
it is preferred to have slightly projecting parts (as shown in the Figures)
on the back plate and valve, so as to allow the steam to keep them
tightly against their respective faces.
Another improvement in steam engines according to this Invention
consists in utilizing a great portion of the sensible and latent heat.
discharged from the engine with the exhaust steam, and also providing
for a simple and easy means of condensation; this is effected by
exhausting the steam from one or more cylinders into a surface con-
denser, where its condensation is effected by forcing or drawing air
through or among the tubes according as the exhaust steam is in contact
with the inside or outside of the tubes. The air being heated in so
passing through or among the tubes is forced or drawn through suitable
passages to the furnace or furnaces of the boiler or boilers, supplying
the whole or part of the air required for combustion of the fuel, the
furnaces and ash-pits being arranged to admit of this being properly
carried out. The efficiency of this system of condensation is greatly
increased by sprinkling water on the surface of the tubes with which
the air is in contact, for the purpose of causing an evaporation on the
opposite side of the tubes to that with which the exhaust steam is in
contact. This evaporation being increased by the air passing through
as aforesaid, causes a strong refrigerating action to take place and
maintains a good vacuum within the condenser; the vapour arising from
this evaporation is carried along with the air to the furnace, increasing
the effective elements of combustion. It is preferred to have the water
dispersed with the air among the tubes in the form of fine spray, but
any convenient method may be used to keep the surface of the tubes
continually moist. This system may be used for condensation without
using the heated air or heated air and vapour for the boiler furnace.
In Sheet 2 of the accompanying Drawings, three different modifi-
cations of this system of condensation are shown in Figures 13, 14.
and 15, all of which are sectional elevations of condensers. In Figure 13.
the steam from the engine enters the condenser H by the branch pipe h,
and is condensed by contact with the outside surfaces of the tubes, which
are kept cool by the air drawn through them in the directions of the
arrows. The water and air from the condensed steam is drawn from

page_text: the condenser by the air pump in connection with the passage or
branch at i.
Figure 14 shows an arrangement where the air is forced through the
tubes, entering by the branch pipe I, and leaving at K, as shown by
the arrows. The steam or vapour on its passage from the entrance h
to the outlet i, is made to pass in the opposite direction to the current
of air inside the tubes.
A method of distributing a small portion of water with the air in
passing through the tubes is shown in this Figure; l, k, are small pipes
lying across the width of the condenser, and perforated on their under
side with small holes, through which water falls upon the several strips
of wire cloth 1, 1, 1, 1, underneath, and from which it is carried off by the
air on entering the tube.
Figure 15 shows an arrangement where the steam is condensed inside
the tubes, the air being drawn through among the tubes. k is the
perforated pipe for distributing the water over the tubes; water from
steam may be used for mixing with the air. In Figures 13 and 15, the
orifices K, K, are in connection with a fan, pump, or other equivalent
instrument which draws the air through the condenser and passes it
through suitable passages to the furnace, or where it may be required.
In Figure 14, the air is passed from the fan or other instrument through
the condenser to the furnace, or where it may otherwise be taken.
Another portion of improvements according to this Invention, and
applicable to all surface condensers in which tubes are used, consists
in fixing the tubes in the tube plates by packing (in the manner of a
stuffing box) a recess round the tube with cord of hemp or other suitable
material with which white or red lead may be used. It is preferred
to have this cord of about one-sixteenth of an inch in diameter, and
the width of the recess such as the cord may fit somewhat tightly against
the tube and tube plate. It is preferred also to have this cord in
one length, and from six to eight coils round each tube, though more or
less may be used.
Figure 16 shows a full-size longitudinal section of two tubes fixed at
one end according to this improved plan; Figure 17 is an end view of
the same. m, m, are the tubes fixed in; n, the tube plate by the cord o,
filling the recess between the tube and the tube plate. The water or
other condensing medium in this arrangement passes through the tubes,
and the vacuum being on the inside of the tube plate; the packings are
held tightly in their recesses without any other fastenings. The covering
plate p is not essential to the efficiency of this mode of fixing the tubes,
but may be used as a safeguard against the packings being ejected from

page_text: their recesses by a high pressure of steam accidently accumulating in
the condenser.
Figures 18 and 19 show how this packing may be applied to the tubes
of condensers where the steam is in contact with the inside of the tubes.
In Figure 19 the covering plate p becomes an essential part of the
arrangement.
An improvement in refrigerators for cooling the water from the con-
denser for re-injection in marine engines consists in having a separate
cistern in free connection with the cold well, or part of the refrigerator
into which the water is discharged after passing through the tubes. It
is preferred to have this cistern at least twice as large as the condenser,
and it may be formed in the keelsons or engine seats, or in the bed-plate
casting of the engine, or it may be with suitable connections in any part
of the ship..
Another improvement in refrigerators is in making the division plates
(which divide the cooling currents so as to make them run in the opposite
direction to the water to be cooled) with a strip of leather, or other
such pliable material, on each side, so as to make a joint with the sides
of the vessel, the pressure of the cooling water in its passage assisting
in keeping these leather strips tight against the sides of the vessel.
Refrigerators with these improvements may be used partly as a surface
condenser in condensing steam from salt water for the purpose of
supplying the waste of fresh water from the boilers of marine engines or
other engines using fresh water.
Figure 20 shows the mode of fitting the division plates in refrigerators,
g being the plate, and the leather or india-rubber for making the joint
against the side of the containing vessel. Figure 21 is a longitudinal
section, and Figure 22 a transverse section of an apparatus combining
these improvements for supplying fresh water by condensation of steam
from salt water. The steam enters by the inlet pipes, s, and is con-
densed in its passage through the tubes in the direction of the arrows
by the cooling water, which entering by the inlet pipe t, passes in a
contrary direction by means of the division plates u, as shown in the
Figures.
In an improved method of regulating the speed of steam engines, the
amount of steam admitted to the engine is proportioned to the amount
of resistance to be overcome. This is conveniently effected by having
that part of the shaft from which the power is taken separate from
the engine shaft, and driven by a clutch or disc having projections on
its face or edge to catch projections on a similar clutch or disc on the
crank shaft; between each of these projections a spring of metal, india-
rubber, or other elastic material is placed, so that the driving power is

page_text: transmitted through the springs.
When the resistance is increased,
the compression on the springs is also increased, and the catches on
the discs approach nearer to each other, thereby giving motion to a
lever in connection with the "throttle," or "cut-off" valves, admitting
a greater amount of steam to the cylinder or cylinders. When the
resistance is lessened, the distance between the catches is increased,
and the contrary motion being thereby given to the lever, a smaller
amount of steam is admitted to the cylinder or cylinders.
Figures 23 and 24 show an arrangement of this improved method of
regulating the speed of motive power apparatus as applied to screw-
propeller engines. L is the disc on the engine shaft M, with projecting
pieces v, v, v, v, between which and the projecting parts w, w, w, w,
on the disc N, are the springs x, x, x, x, through which the propeller
shaft. O is driven. The different relative positions of the two discs,
according as the resistance is greater or less, as already explained,
actuates the grooved pulley y (in connection with the " throttle" or cut-
off valves), by means of inclined planes z, z, on the disc N, acting on
one side of the pulley y, through the sliding bars 1, and the springs 2
acting on the other side of the pulley.
In one modification of an improved boiler according to this Invention,
a series of rows of tubes are placed vertically on each side of the fire
grate; these tubes are in free connection with flat hemispherical or other
conveniently shaped chamber at both ends, the upper chambers having
water and steam spaces. Between these chambers and directly over the
(according to the width of the fire grate) in connection with and having
the same water level as the upper chambers. The steam spaces in these
chambers and cylindrical vessels are connected to one or more steam
receivers, from which the steam is supplied to the engine. In this boiler
the fire gases first act on the cylindrical vessels over the grate, they
then pass through among the upper ends of the tubes on either side,
then descending cross among the lower ends of the tubes, and from
thence ascending by a flue or flues, pass round the steam receiver or
fire grate, are one, two, or more small horizontal cylindrical vessels
receivers before entering the chimney.
Figure 25, Sheet 2 of the Drawings, is a sectional elevation of an
arrangement of this improved boiler; P, P, being the vertical tubes on
each side of the fire grate Q, with the chambers R, R, at each end. S,
the cylindrical vessels over the fire grate; the arrows show the direction
of the fire gases among the tubes to the flues T, T, through which they
pass to the back of the boiler and ascend by a flue (not shown in the
Drawings), and return to the front round the steam receivers U, U.
Instead of placing the tubes vertically they may be conveniently

page_text: arranged horizontally, and in free connection with water chambers at
both ends, the small horizontal vessels being not only over the fire grate
as in the arrangement previously described, but extending also over the
tubes and connected with their chambers, the fire gases circulating as
in the arrangement previously described.
Figure 26, Sheet 3 of the Drawings, is one half of a boiler in vertical
section according to this last arrangement.
These arrangements may be modified in various ways, such as having
the fire grate placed so that the fire gases may pass among the lower
ends of the tubes and recross at the upper ends, part of the fire gases
acting on the vessels above as before described. They may also be
without vessels over the fire grate, or the tubes may be at one side of
the grate only.
Figures 27 and 28, Sheet 3 of the Drawings, are each one half of a
boiler in vertical section, embodying part of these modifications. The
diameters of these cylindrical vessels range from twelve to twenty-four
inches, and that of the tubes from two to six inches, though other sizes
may be used.
In other modifications of improved boilers according to this Invention,
instead of having a combination of cylindrical vessels with small tubes
and chambers as already described, the boilers may be wholly com-
posed of horizontal or nearly horizontall cylindrical vessels of the same
or nearly the same size.
In one modification of a boiler on this plan the fire grate is placed
underneath one, two, or more horizontal vessels; below each of these
are one or more series of similar vessels, but shorter by the length of
the furnace. The upper side of the lower vessels are connected with
the under side of the vessels above, in one or more places. The fire
gases pass first backwards underneath the vessels over the fire grate,
then downwards through the series below, continuing as shown in
Figures 29 and 30, Sheet 3 of the Drawings, which are respectively
transverse and longitudinal sections of such a modification of boiler as
described. In this improved boiler the lower cylindrical vessels instead
of being behind the furnace may be placed on each side of it, and the
fire gases circulate as in the arrangement last described.
In another modification of these boilers the fire grate is underneath
the lower course of vessels, and the gases pass first backwards under the
lower course, then return underneath the second course above, then
return again backwards under the next course above that, returning
still higher round the steam receivers before passing to the chimney..
Figures 31 and 32 are respectively transverse and longitudinal sectional
elevations of a set of such a modification of these improved boilers; and

page_text: Figures 33 and 34, transverse sections of arrangements having two
courses only of cylindrical vessels combined with steam receivers. When
these vessels are made with flues or tubes through them the fire gases
may pass underneath the vessels and return through their flues or tubes,
or they may pass underneath and through the vessels at the same time
or through one series and underneath the series above at the same
time.
In an improved cylindrical boiler according to this Invention the
furnace is underneath the boiler and the whole under half of the boiler
is exposed to the action of the fire gases, which after passing underneath
to the back end return through one, two, or more flues or tubes in the
lower part of the boiler to the front, they then pass backwards through
a higher set of flues or tubes, after which they may either pass round a
steam receiver (preferred to be horizontal) above the boiler, or direct
into the chimney. Figures 35 and 36 show this arrangement of boiler.
This improved boiler may also have the fire gases returning to the front
through both series of flues or tubes at once, and then backwards round
the steam receiver to the chimney. When two boilers of this description
are placed together one steam receiver may be raised for both.
In another improvement comprehended in this Invention the greater
portion of the heat contained in the fire gases after leaving the boiler is
recovered and made available in promoting the combustion of the fuel.
This is effected by passing the fire gases in one or more courses through
a set of tubes placed conveniently at the under part of the chimney. A
current of air (preferred to be running in the opposite direction to the
fire gases) is forced or drawn through or among these tubes on the
opposite side to that with which the fire gases are in contact. Water is
dispersed among the tubes, causing an evaporation and refrigerating
action as in the condenser described in this Specification, the air and
vapour carrying off the heat of the fire gases to the furnace or furnaces
through suitable passages. An arrangement of this kind is shown in
Figures 31 and 32, V being the vessel containing the tubes amongst
which the fire gases circulate, as shown by the arrows. Water is dis-
persed with the air on its passage through the tubes by the pipes 3
and 4, which may contain the water in the form of steam.
Having thus particularly described my said Invention and the manner
in which the same is or may be used or carried into effect, I have to
state that I do not restrict myself to the precise details herein-before
described or delineated, and that I do not claim to have invented every
separate detail herein-before described or delineated; but what I con-
sider to be novel and original, and claim as the Invention secured to me
by the herein-before in part recited Letters Patent, is,—

page_text: First, the placing of two high-pressure cylinders on the end of a low-
pressure cylinder, so that the piston rods from the high-pressure
cylinders unite with the piston rod or rods from the low-pressure
cylinder, substantially as herein-before described, an example thereof
being shown in Figures 1 and 2, Sheet 1 of the accompanying Drawings.
Second, the placing of two high-pressure cylinders on the end of a
low-pressure cylinder from which the connecting rod works through a
trunk between the two high-pressure cylinders, substantially as herein-
before described, an example thereof being shewn in Figures 3 and 4,
Sheet 1 of the accompanying Drawings.
Third, the combining of three cylinders of different diameters in one
engine, substantially as herein-before described in connection with
Figures 5 and 6, Sheet 1 of the accompanying Drawings.
Fourth, the combining of two high and two low pressure cylinders in
one engine, substantially as herein-before described, an example thereof
being shown in Figures 7 and 8, Sheet 1, of the accompanying Drawings.
Fifth, the arrangement by which the pressure of the steam is wholly
or partly relieved from slide valves, and in which the pressure of the
steam itself assists in securing the efficiency of the arrangement sub-
stantially as herein-before described in connection with Figures 9, 10, 11,
and 12, Sheet 2 of the accompanying Drawings.
Sixth, the condensation of steam in surface condensers by means of
air forced or drawn through or among the tubes, substantially as herein-
before described in connection with Figures 13, 14, and 15, Sheet 2 of
the accompanying Drawings.
Seventh, the condensation of steam in surface condensers by means
of air and water forced or drawn through or among the tubes where the
water is used to cause a refrigerating action by evaporation, substan-
tially as herein-before described in connection with Figures 13, 14,
and 15, Sheet 2 of the accompanying Drawings.
Eighth, the use of the heat given off by the steam in condensation in
promoting the combustion of the fuel in the steam boiler furnace, sub-
stantially as herein-before described.
Ninth, the method of fixing tubes in surface condensers by means of
a cord of hemp or other suitable material, as herein-before described in
connection with Figures 16, 17, 18, and 19, Sheet 2 of the accompanying
Drawings.
Tenth, the use of a separate cistern in connection with refrigerators,
as herein-before described.
Eleventh, the use of a strip of leather, or such pliable material, on
the edges of the division plates of refrigerators, as herein-before

page_text: described, an example thereof being shown in Figure 20, Sheet 2 of the
accompanying Drawings.
Twelfth, the apparatus for supplying fresh water by condensation as
herein-before described in connection with Figures 21 and 22, Sheet 2
of the accompanying Drawings.
Thirteenth, the regulating the supply of steam to steam engines in
proportion to the amount of resistance to be overcome, substantially as
herein-before described in connection with Figures 23 and 24, Sheet 2 of
the accompanying Drawings.
Fourteenth, the improved arrangements of steam boilers herein-before
described, and shown in Figures 25 to 36, Sheets 2 and 3 of the accom-
panying Drawings.
Fifteenth, the recovering and using the heat contained in the fire
gases after leaving the boiler, substantially as herein-before described,
an example being shown in Figures 31 and 32, Sheet 3 of the accom-
panying Drawings.
In witness whereof, I, the said James Howden, have hereunto set
my hand and seal, this Eighteenth day of May, in the year of our
Lord One thousand eight hundred and sixty-one.
JAMES HOWDEN. (L.S.)