CERTAIN IMPROVEMENTS IN THE STEAM ENGINE, AND ITS APPLICATION TO THE NAVIGATION OF VESSELS
Year: 1845

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, STEPHEN
HIGGINSON PERKINS, of Charlotte Street, Bedford Square, in the County of
Middlesex, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Eighteenth day of
September, in the ninth year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto the said Stephen Higginson Perkins, Her
especial licence, that I, the said Stephen Higginson Perkins, my exors,
admors, and assigns, or such others as I, the said Stephen Higgirsson
Perkins, my exors, admors, and assigns, should at any time agree with,
and no others, from time and at all times during the term of years therein
expressed, should and lawfully might make, use, exercise, and vend, within
England, Wales, and the Town of Berwick-upon-Tweed, and also within all
Her Majesty's Colonies and Plantations abroad, an Invention of "CERTAIN
IMPROVEMENTS IN THE STEAM ENGINE, AND ITS APPLICATION TO THE NAVIGATION OF
VESSELS," being a communication from a foreigner residing abroad; in which
said Letters Patent there is contained a proviso that I, the said Stephen
Higginson Perkins, should, by an instrument in writing under my hand and
seal, particularly describe and ascertain the nature of the said Invention, and-

page_text: in what manner the same is to be performed, and cause the same to be inrolled
in Her Majesty's High Court of Chancery within six calendar months next
and immediately after the date of the said in part recited Letters Patent,
as in and by the same, reference being thereunto had, will more fully and at
large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Stephen Higginson Perkins, do hereby declare that the nature of the said
Invention, and in what manner the same is to be performed, are particularly
described and ascertained in and by the present Specification thereof, reference
being had to the Drawings hereunto annexed, that is to say :-
The nature of the said improvements in the steam engine consists in
employing two cylinders, the pistons of which are connected to cranks placed
at right angles or nearly so, and in which the steam is made to act simul-
taneously on both pistons during part of the stroke, by keeping a free com-
munication open during the same part of the stroke between the said two
cylinders, whereby the steam is worked highly expansively, and a more regular
force obtained than there would be by working the steam expansively to the
same high degree in ordinary crank engines, and a great saving of fuel is thus
effected, which is augmented by applying a centrifugal suction and blowing
apparatus to the exit flue of the boiler that supplies them with steam, which
apparatus is made to draw the hot air from the exit flue, and force it through
a heater composed of a series of small tubes, through which the feed water
passes on its way to the boiler. And the nature of the said improvements in
the application of the steam engine to the navigation of vessels (having
reference more particularly to such as are propelled by spiral stern propellers),
consists, firstly, in employing a cylindrical drum or wheel, which I call the hydro-
static rotator, attached to the propeller shaft, and made to revolve within a
cylinder by hydrostatic pressure acting on radial sliding wings in the circum-
ference of the rotator, which hydrostatic pressure is obtained by means of
pumps attached to the piston rods of the steam cylinders, the fluid used being
conveyed through pipes connecting these pumps with the cylinder which
contains the rotator; and, secondly, in employing a hollow shaft attached to the
axis of the rotator, which admits the propeller shaft to be drawn in and out, for
the purpose of disengaging the propeller, by means of a radial arm attached to a
shaft supported by a bearing bolted to the side of the stern post. And the
manner in which the said Invention, in the several parts thereof, is performed,
is represented in the Drawings hereunto annexed as aforesaid, and in the
following description thereof.

page_text: DESCRIPTION OF THE DRAWINGS.
Figure 1 represents a top view, on an enlarged scale, of the steam
cylinders, crank shaft, and pumps herein-before mentioned. A, A, is the crank
shaft; a, a', cranks placed at right angles; a", a¹¹, connecting rods for com-
municating the force of the pistons to the said cranks in the usual manner;
B, larboard cylinder, and b its piston; C, starboard cylinder, and c its piston;
D, D', slide valves, worked in the ordinary manner, for conveying steam to and
from the said cylinders; d, d, eduction pipes for conveying the steam into ordinary
condensers; E, main steam pipe for conducting the steam from the boiler to
the cylinder B; e is a throttle valve in the main steam pipe worked in the
ordinary manner, to be opened when the piston 6 commences its stroke, and
to be closed when the same has travelled about one half the length of the
cylinder B; F, f, slide valves, which open or close a communication between
the cylinders B and C, these valves being worked either by tappet wheels or
eccentrics applied to the crank shaft, and so arranged that when the piston c
commences its movement from right to left, the slide valve F will be opened
and closed when said piston shall have performed half its stroke, the slide valve
f being at the same time so arranged as to open when the piston c commences
its movement from left to right, and to close when said piston is at half stroke.
G is a small steam pipe, communicating with the steam boilers, and g a stop-
cock therein, for shutting off the communication with the boilers H; and J,
double-acting force pumps; h and j, buckets attached to an extension of the
piston rods of the pistons c and 6; K, main suction pipe; k, k, k, k, branch
suction pipes for supplying the pumps H and J; L, a receiver; 1, 1, 1, pipes
for conducting the fluid from the pumps to said receiver; M, main pipe for
conducting the fluid from said receiver.
Figure II. represents a longitudinal section on the centre line of the boiler,
centrifugal apparatus, and heater; and Figure III. a transverse section of the
heater. N, N, longitudinal section of an ordinary marine boiler; n exit of the
flues into the chimney; n', n", a damper placed in the lower part of the
chimney for shutting off the communication between the exit flue and the
chimney when the centrifugal apparatus is to be put in operation. O, a cylin-
drical box containing a centrifugal blower or fan wheel; o, o, pipe forming a
communication between the exit flue of the boiler and the centre of the fan
wheel; o¹, pipe for conveying the air from the centrifugal blower under the
heater. P, P, a box made of sheet iron, containing a series of small tubes, the
centre one of which is marked p. These tubes are inserted into corresponding
sides of two boxes Q, Q, and R, R, Figure III., these boxes being provided
with a series of partitions 9, 9, 9, 7, I, I, I, r, r, r, r, r, r, r, so placed as to form

page_text: an alternating communication between the ends of said tubes. S, a pipe com-
municating with the force pump which supplies the boiler and the upper
compartment of the box R, R; 8, pipe for conveying the water from the lower
compartment of the box Q, Q, to the boiler. The course of the water, in
passing from S to s, through the series of tubes, is indicated by the dotted
arrows. T, box below the heater, which receives the hot air from the centri-
fugal apparatus, previous to its entrance and distribution among the series of
tubes; t, pipe for conducting the air from the heater to the chimney n¹, above
the damper n".
Figure IV. represents a longitudinal section, Figure V. a transverse
section, Figure VI. a side elevation, and Figure VII. an end view of
the hydrostatic rotator. U, U, a cylinder made of cast iron or composition
metal, provided with four apertures u, u, u¹, u¹; V, V, covers bolted to the
ends of said cylinders at u, v, v, v; W, an axis revolving in bearings w, w,
formed in the centres of the covers V, V; X, a wheel or drum attached to the
axis W, composed of a thick rim, and six solid spokes extending the whole
width of the rim ; x, x, x, x, x, x, parallel cavities in the said spokes; Z, Z¹, Z³,
Z³, Z, R', metallic wings or sliding pieces made to fit the said cavities with
great accuracy; 1, 1, 1, 1, 1, 1, springs inserted in the bottom of said cavities,
for the purpose of pressing these sliding pieces against the inside of the cylinder
U, U; 2, 2, 2, 2, 2, 2, holes through said sliding pieces, for establishing an
equilibrium of pressure around them; 3, 3, metallic segments attached to the
inside of the cylinder U, U, of equal width with the rim of the drum, and
formed into inclined planes at 4, 4, 4, 4', excepting at the apertures u, u,
u', u', where they terminate abruptly, as shown in the Drawing 5, 5, circular
discs firmly attached to the ends of the drum X, at a distance equal to the
length of the cylinder U, U; 6, 6, cavities formed between the covers V, V,
and discs 5, 5; 7, 7, lugs cast on the covers V,V, and bolted to the timbers
8, 8, for supporting the machine.
Figure VIII. represents a stern view, and Figure IX. a longitudinal
section of the stern of a steam vessel, giving a general view of the
before-described improvements, the same letters of reference being used in
this Figure to represent the parts corresponding with those in the Figures
before described. 9 is a hollow shaft attached to the axis W of the
hydrostatic rotator; 10, propeller shaft passing through a stuffing box 10'
In the stern, provided with a feather 11 made to fit a corresponding groove
within the hollow shaft 9; 12, a grooved ring attached to the propeller shaft,
for moving the same in and out in the hollow shaft by means of a lever fork,
or other usual contrivance; 13, side view of a spiral propeller; 14, an elonga-

page_text: tion of the nave thereof, which elongation, as well as the nave itself, is provided
with a square hole in the centre, corresponding to a square at the end of the
propeller shaft; 15, an arm made of wrought iron or composition metal
attached to a shaft or axis 16, which shaft also passes through a stuffing box
161 in the stern, the lower end of said arm being provided with an eye or
bearing by which the projecting nave of the propeller is held, and in which it
may revolve; 17 and 18, bearings attached to the side of the stern post of the
vessel, for the purpose of supporting the propeller shaft and the shaft 16; 19,
a toothed quadrant attached to the inner end of said shaft; 20, a tangent
screw, working in the teeth of said quadrant, and moved by the handle 21, for
raising or lowering the propeller by the before-named metallic arm; 22, the
rudder; 23, a slit cut in the same, opposite the propeller shaft, for admitting
the requisite angular movement of the rudder in steering.
Figure X. represents an end view of the arm 15 drawn to an enlarged scale,
in which the bearing for holding the elongated nave of the propeller will be
more clearly seen. Figure XI. is a side view of the said elongated nave, and
Figure XII. a side view of the square end of the propeller shaft, both drawn
to an enlarged scale; the hole in the nave being indicated by dotted lines.
Figure XIII. is a sectional plan of the extreme point of the stern of the vessel
through the centre line of the propeller shaft. 18 is the bearing attached to
the side of the stern post, for supporting the shaft; 22, rudder; 23, a slit cut
in the same, opposite the propeller shaft, in order to admit the necessary
angular motion being given to the rudder.
Having thus particularly described the said improvements in the steam
engine, and its application to navigation, I will now proceed to explain the
manner in which the same are to be put into operation. In starting the
engine, the throttle valve e and the stop-cock 9 should be kept open whilst
steam is admitted from the boiler, through the steam pipes E and G; but as
soon as motion has thereby been obtained in the engine in the ordinary manner,
the stop-cock g should be shut, as shewn in the Drawing; and the throttle e
should be allowed to open and close, in the manner herein-before described, for
the purpose of working the steam expansively in the cylinder B. It will now
be seen that the pressure of the steam on the right side of the piston 6 will, by
means of the piston rod, and the connecting rod a¹¹¹ and the crank a¹, give a
left-handed movement to the crank shaft A, which movement will cause the
crank a to pass its centre with an upward movement, and thus attain a
position which will enable the piston c to exert its force in giving also a left-
handed movement to the crank shaft A. It is evident that when the piston b
has arrived at the termination of the stroke, the piston c is at half stroke.

page_text: The slide valve F being now shut, the steam contained within the cylinder C,
on the right side of its piston, will, by its expansive force, cause the piston c to
continue its movement to the termination of its stroke, whilst the due action
of the slide D will in the meantime have releived the pressure on the right of
the piston b, by admitting the steam into the condenser through the pipe d.
It is also evident, from the right angular position of the cranks a, a', that at
the moment the piston c has arrived at the termination of its stroke, the piston
b will again have assumed the position marked on the Drawing. At this
moment the slide valve f is opened, and the pressure of the steam in the
cylinder B, on the left side of the piston b, will give c the necessary retrogade
movement to the right, whilst the slide D¹ will have relieved the pressure on
the other side of the piston, by opening the necessary communication with the
condenser. Thus it will be seen that the steam admitted into the cylinder B
by the main steam pipe E will, during half the stroke of the piston b, exert
its entire force thereon; but during the remaining half of the stroke, whilst the
throttle e is kept shut, the steam will act simultaneously on both pistons c and
b; and that during the latter half stroke of the piston c, while the slide valve
F is kept shut, the steam in the cylinder C, obtained solely from the cylinder
B, will cause the piston c to complete the stroke. In this manner the steam
actuating the engine may be worked highly expansively, and still a suffi-
ciently regular force will be imparted to the crank shaft by the pistons, and
a great saving of steam and fuel be thus effected. It should here be particu-
larly noticed, that if steam of considerable pressure is admitted into the
cylinder B, it will be well to make the cylinder C of greater capacity than the
cylinder B, in order to obtain a more equable force from each engine. In
applying this engine to ordinary steam vessels with paddle wheels, the crank
shaft A, A, is extended, as shown by the dotted line A', A', and the paddle
wheels are applied at the extremities as usual; but when applied for the
purpose of giving motion to the hydrostatic rotator before described, the crank
shaft A, A, is cut short, as shewn in the Drawing, and the piston rods of the
pistons c and b, extended for working the double-acting force pumps II and J.
It will be seen by the position of their valves, that these pumps will draw in
any fluid admitted into the pipe K, and force the same into the receivers L
and pipe M.
I proceed now to describe the manner in which the centrifugal apparatus
and heater operate in connection with the steam boiler. In first lighting the
fire and raising the steam, the damper n" should be kept open, in order that
the natural draft in the chimney may be employed for supporting combustion
in the furnaces; but as soon as the steam is raised, and the engine put in opera-

page_text: tion, this damper should be closed, and the wheel of the centrifugal apparatus
made to revolve rapidly in the direction of the arrow at O, which may be done
either by bands and pulleys connected with the engine shaft in the usual
manner, or by a separate small steam engine; the effect of which motion will
be to draw the hot air out of the flues of the boiler, and force the same through
the spaces between the tubes of the heater. It will now be seen that since the
cold water from the force pump, in its passage to the boiler as before described,
is made to enter the small tubes at the upper part of the heater, this water
will become gradually heated in descending the series of tubes, and that
thereby the hottest part of the air from the centrifugal apparatus will come in
contact with the warmest part of the tubes of the heater, whilst the air in its
ascent between these tubes, as it gradually cools, will come in contact with the
coldest part of said tubes at the upper part of the heater, and thus the heat
will be effectually taken up before entering the chimney through the passage
t, and a great saving of fuel be effected.
I have next to notice the operation of the hydrostatic rotator. By reference
to Figure IX. it will be seen that the pipe M, which receives the fluid from
the force pumps, and in which the fluid is kept under a heavy hydrostatic
pressure, communicates with the apertures u, u, of the rotator, and also that
the pipe K, through which the fluid is drawn into the pumps, and in which
the fluid is not kept under pressure, communicates with the apertures u¹, u¹.
By inspecting the transverse section represented in Figure V., it will be seen
that the fluid entering at the two apertures u, u, will exert equal force in
precisely opposite directions, and that therefore its hydrostatic pressure, how-
ever great, being thus perfectly balanced, will not cause any friction in the
axis W. It will also be seen that the hydrostatic pressure against the sliding
piece Z acts in opposite directions to the hydrostatic pressure exerted against
the sliding piece Z³, thus imparting a rotary movement to the wheel X pro-
portionate to the force of the hydrostatic pressure under which the fluid is
kept, and to the extent of the protruding surface of these sliding pieces beyond
the circumference of the wheel. By further inspecting Figure V. it will be
seen, that during the rotation of the wheel X to the right, the sliding pieces
Z and Z will advance down the inclined planes 4, 4, until they touch the
inside circumference of the cylinder U, U, so that by the time the sliding
pieces Z and Z³ arrive at the apertures u³, u¹, and begin to ascend the inclined
planes 4, 4, the said sliding pieces Z³ and Z³ are placed in positions to
receive the force of the fluid; the remaining sliding pieces will move in like
manner down these inclined planes in succession, and thus a constant rotation
with a uniform force will be imparted to the wheel X by means of the hydro-

page_text: static pressure of the fluid forced through the pipe M. It is particularly
worthy of remark that the axis W is not exposed to any pressure besides that
produced by the weight or gravity of the wheel with its springs, sliding pieces,
and discs; and that hence the whole force of the hydrostatic pressure against
the sliding pieces, with the exception merely of their friction, is exerted in
giving rotation to the said axis W. It is also worthy of remark that the
hydrostatic rotator, whilst it may be made to revolve at a speed many times
greater than that of the crank shaft of the engine, may be placed in the very
extreme part of the run of the ship, whilst the steam engine which gives
motion to the same is placed in the forward or middle part; there being no
other connection between the two than the pipes, which may be placed in its
very bottom, there is no machinery which will interfere in the least with any
desirable arrangement in the vessel. I have to observe that whenever it is
desirable to turn the rotator at a velocity of two revolutions per second, the
radial movement of the sliding pieces should not exceed one thirtieth part of
the diameter of the cylinder containing it.
It remains lastly to notice the manner of disengaging the propeller from
the axis of the hydrostatic ratator, and of lifting or unshipping the same,
The propeller shaft 10, by means of the grooved ring 12 and the forked lever
as before described, is drawn into the hollow shaft, and thus withdrawn from
the square hole in the nave of the propeller. The propeller being held by
the eye or bearing in the lower part of the arm 15, it will be lifted up by
giving half a revolution to said arm by means of the toothed quadrant and
the tangent screw before described. By reversing this operation the propeller
may be reshipped and connected to the propeller shaft.
And having now fully described the nature of the said Invention, and in
what manner the same is to be performed, I declare that I lay no claim to
the pistons, cranks, rods, or other known parts in the steam engine herein-
before described; but what I do claim is,-
First, the admitting the steam from the boiler into one cylinder only, and
the working the steam expansively in the said cylinder, together with the
employing the steam to act simultaneously on both pistons during part of the
stroke, as herein-before described, by opening a communication alternately
between the two cylinders, whilst at all times a vacuum is kept up in both
cylinders, on the opposite sides of each of the pistons to that on which the
steam acts.
Second, the employing in the manner herein-before described of the heat
which has hitherto been wasted in ordinary marine boilers.
Third, the application of force pumps to a steam engine for forcing oil,

page_text: water, or other suitable fluid, through pipes or other conductors, into any appa-
ratus capable of imparting, by means of such fluid, rotary movement to a spiral
propeller placed at the stern.
Fourth, the combination with force pumps attached to a steam engine of the
hydrostatic rotator herein-before described, for the purpose of giving motion to
a spiral stern propeller.
Fifth and lastly, I claim as my Invention the disengaging the propeller from
the propeller shaft, and the raising and lowering the same in the manner
herein-before described.
In witness whereof, I, the said Steven Higginson Perkins, have hereunto
set my hand and seal, this Ninteenth day of September, in the year
of our Lord One thousand eight hundred and forty-five.