CERTAIN IMPROVEMENTS IN MACHINERY FOR PROPELLING VESSELS AND OTHER FLOATING BODIES MOVED BY STEAM OR OTHER POWER
Year: 1836

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
PICKWORTII the younger, of Sipson, in the County of Middlesex, Gentleman,
send greeting.
WHEREAS His present most Excellent Majesty William the Fourth, by
His Letters Patent under the Great Seal of Great Britain, bearing date the
Twenty-sixth day of January, in the sixth year of Ilis reign, did, for Himself,
His heirs and successors, give and grant unto me, the said Henry Pickworth,
Tis special licence, full power, and privilege and authority, that I, the said
Henry Pickworth, my exors, adññiors, and assigns, or such others as I, the
said Henry Pickworth, my exors, adfiiors, or assigns, shall at any time agree
with, and no others, from time to time and at all times during the term of
years therein expressed, should and lawfully might make, use, exercise, and
vend, within England and Wales, and the Town of Berwick-upon-Tweed, and
also in His said Majesty's Colonies and Plantations abroad, my Invention of
"CERTAIN IMPROVEMENTS IN MACHINERY FOR PROPELLING VESSELS AND OTHER
FLOATING BODIES MOVED BY STEAM OR OTHER POWER;" in which said Letters
Patent is contained a proviso, that I, the said Henry Pickworth, shall cause a
particular description of the nature of my Invention, and the manner in which
the same is to be performed, to be enrolled in His 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.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Henry Pickworth, declare that the nature of my said invented improvements,
and the manner in which the same are to be performed, are fully set forth
and explained in the Drawings hereunto annexed, and in the following
description thereof, that is to say:-
Figure 1, of the set of Drawings marked No. 1, is a side view of a paddle
wheel constructed according to my said improvements, with one half of the body
of the wheel and one half of the floats left out, in order to render the Figure
more intelligible; and Figure 2 is an end thereof; the same letters referring
to the same parts on both Figures. The wheel is supposed to be in action.
The body of it (H, H,) consists of two sets of radial arins (or their equi-
valents), firmly fixed on that part of the main shaft (A) which projects beyond
the side of the vessel, a space being left between each set of arms to receive
the paddle frames I, I, and the paddles (K, K.) D is a hollow shaft moveable
in a collar, the bore of which hollow shaft is of such dimensions that the main
shaft A shall just be able to work within it without touching it. To the outer
end of this hollow shaft, and as near to the outer side of the vessel as may be
found convenient, there is firmly fixed an eccentric E; and to the inner end,
which is within the vessel, there is fixed a wheel B, similar to the steering
wheel in large vessels, and applicable to somewhat similar purposes. C is a
cog wheel for palls to act on, so that the said hollow shaft D, and thereby the
eccentric E, may be fixed or moved at will. A wheel and pinion may be sub-
stituted for the said steering wheel and cog wheel. On the eccentric E there
revolves a wheel F, called the frame governor, which carries the same number
of radial arms (or their equivalents) as the body of the wheel, and is of the
same diameter. From the periphery of one side of the body of the wheel to
the periphery on the other side of it there passes in a horizontal line a revolving
bar, the outer end of which is pinned, and the inner end of which terminates
in a crank (G). As many bars are requisite at regular and equal intervals as
there may
be paddles required. The length of the crank (G) is determined
by the distance between the centre of the main shaft and the centre of the
eccentric. The extreme ends or necks of the cranks are passed through the
periphery of the frame governor (F), and there secured at equal distances. To
each of the revolving bars there is firmly fixed a frame of metal (I), of a
regular form, one half of which is on one side of the bar and one half on
the other in the same plane with the crank. The purpose of this frame is to
support the moveable float board, which may be suspended from it in a variety
of ways.
In the set of Drawings hereunto annexed, marked No. 2, Figure 1 exhibits

page_text: another form of arrangement on the same principle, which it may be expedient
under certain circumstances to adopt. In this Figure most of those parts are
omitted which have been previously explained in describing the set of Drawings
marked No. 1, and are common to both. The frame governor (F) in particular
is here for the sake of clearness left out, but the face of that part of the body
of the wheel between which and the side of the vessel the frame governor
should be inserted is fully shewn. The wheel is supposed to be at rest, and the
paddle frame open. On inspection of this Figure (Figure 1 of No. 2) it will
be seen that the revolving paddle frames (which are distinguishable from the
fixed frames by their larger size and their being furnished with cranks) at
the bottom of the wheel have the broadest part of the paddles to the left
hand, and that the fixed frames have the broadest part of their paddles to the
right. Let it now be supposed that these bottom paddles are set in motion
from the right hand towards the left, and it will be manifest that the pressure
of the water will act on the paddles of the revolving frames and close them,
the broadest sides of the paddles being in advance of the motion of the body,
and fixed at an angle to favor this action. The fixed frames between the lower
revolving frames have the broadest part of their paddles in the rear of the
said motion, and consequently these frames remain open; the effect must of
course he that the vessel will be propelled ahead by the revolving paddles,
which always act in the most favorable direction, that is to say, at right angles,
or nearly so, with the plane of floatation. Suppose, on the other hand, the said
motion continued, while by a heavy sea or other contingency the entire wheel
is submerged, the lower paddles would continue to act as before described,
while the paddle frames both revolving and fixed that are above the centre of
the wheel having the broadest part of their paddles in the rear of the said
motion, the frames will remain open, and the wheel continue nearly as
effectual a propeller as before.
The frame 1, Figure 2 of Number 2, consists of a series of parallel bars, placed
vertically at regular and equal intervals, and the paddle board is made in parts
(one of which is represented by the Figures K¹) to fit into the spaces of the said
frame.
P represents the vertical bar of the paddle board. Each part of the
paddle board turns on an axis at top and bottom, which axis, instead of being
placed in the centre of the line forming the end of the parellogram, is a short
distance therefrom, so that there may be a preponderance of pressure on one
side of the axis. The float boards of Numbers 1 and 2 are so attached to the
frames as to be in advance of the circular motion of the body when below the
main shaft, and in the rear thereof when above it. The pressure will then
make them fall into their places and produce the required propulsive effect,

page_text: after which they will be turned by the back water (if the depth of the wheel
in the water be such as to create any), and will then present themselves in
an oblique position to the water.
Figure 3 of Number 2 is a separate view of the fixed paddle frames I 2.
R, R, are screws, with which it is attached to the body of the wheel; K", the
paddle board; and P 2, the vertical paddle frame bar. Should it be preferred
to have the power of checking the way of the vessel after the manner of
the common paddle wheel instead of the manner herein-before described,
this may be effected as follows:-In each of the intermediate spaces between
the revolving frames II, Figure 1 of No. 2, from which the paddles are sus-
pended, there are fixed frames and float boards, of the construction shewn in
Figure 3 of No. 2, at equal distances from the two revolving frames next in
contiguity and unconnected with the frame governor (F), and the said fixed
frames are firmly fastened at one end to the perepriphery of the body of
the wheel, and point at the other end to the centre of the main shaft, and
are secured in that position. The floats must be so adjusted in the frames
that when the wheels is propelling the vessel ahead these floats shall
present themselves in an oblique position to the water; but the vessel
having headway upon her, and the wheel being stopped, a resistance like
that of the common paddle wheel will be offered to her progress, and a
reverse motion of the main shaft will instantly give the back action. From
the alternately opposing and yielding action given to the floats of wheels
constructed according to either of the arrangements represented in the
Drawings Number 1 and 2, the wheels may be submerged without the pro-
pelling power being reduced in any material degree. To retain the paddle
boards in Nos. 1 and 2 at right angles with the side of the vessel when
propelling, and at right angles with the frames, or nearly so, when not pro-
pelling, suitable stops are affixed to the frames or to the paddles, which stops
may consist of projections on the bosses (N, N). The float board moving from
its propelling position should never be allowed to attain to a perfect right angle
with the frame, a slight deviation therefrom being necessary to render the action
speedy and certain. Back action is produced by one half turn of the steering
wheel B, accompanied by the usual reverse motion of the main shaft, which may
be simultaneously effected. In rivers and other places where great care is
necessary, it is intended, according to both the arrangements, Number 1 and
Number 2, that a man shall be stationed at the steering wheel B, who with his
foot may command the pall or palls acting on C, and by turning the wheel D
augment or diminish the power of the paddles on his side of the vessel without
One half turn of this steering
interfering with the action of the main shaft.

page_text: wheel, when the centre of the paddle wheel is above or nearly level with the
line of flotation, and when the paddles are in full action, renders them entirely
passive; and this movement being performed on one side of the vessel while
the paddles on the other side remain in full force, the vessel is brought short
round upon her heel. The force requisite for this purpose is very small, as
the eccentric itself will for the most part revolve so as to keep pace with the
body of the wheel when the pall is removed from the rack-work C. The
half turn of the wheel B, which, under the circumstances aforesaid, renders
the paddles passive, will, in the case of a wheel entirely submerged, give back
action nearly equal to the forward action on the opposite side of the vessel.
By restricting the opening of the paddles to an angle of 45°, or thereabouts,
with the frame and with the side of the vessel, a sufficient resistance may be
at all times obtained to arrest the way of a vessel, and to give back action by
merely reversing the motion of the main shaft, and this without any material
sacrifice of speed if the wheel should not be deep in the water. One wheel in
the centre of the bottom of the vessel may be used instead of two wheels, or two
wheels may be there placed side by side entirely out of reach of gun shot. A
double keel would, I apprehend, furnish abundant protection for the paddles
from the ground. No alteration in the trim of a vessel would materially affect
the wheel or wheels, whether placed at the sides or in the centre of the bottom,
as it is intended that they shall be placed so deep as to have at all times and
in all weathers a firm hold of the water; and by so placing the paddles that
the broadest parts shall turn towards the side of the vessel as they close,
should even a sea strike the whcel on her broadside, no injurious effect would
be produced, as the paddles would present their edges to the shock. The
advantages of the arrangement shewn in Number 2 are, that by merely
stopping the engine a powerful drag will be thrown on the vessel's way by the
closing of the fixed frames, which will be effected by the floating medium
coming first in contact with the broadest part of the paddles in the fixed
frames. If the motion of the main shaft be reversed the vessel will be
propelled astern, as in the case of the common wheel, so that without moving
the eccentric the vessel may be propelled either way. The fixed frames will give
these further advantages, namely, that the heaviest strains upon the paddle
wheel will be entirely removed from the parts most exposed to derangement,
and thrown upon the body of the wheel, which has all the strength of the
common paddle wheel.
And I may further observe, that to provide against
accidents to the revolving paddle frames the fixed frames are pierced so as to
receive an iron rod, the insertion of which will instantly prevent the paddles
in the fixed frame from turning on their axis, and convert the wheel into the

page_text: common paddle wheel. The fixed frames may be so secured as to be easily
removed when desired without disturbing any part of the machinery.
The set of Drawings annexed, marked Number 3, representing a third
arrangement. Figure 1 is a side view, and Figure 2 an end view, of a wheel
constructed according to this particular modification. The hollow shaft and its
eccentric are here dispensed with, and instead thereof the frame governor is
made to run over either fixed points or friction rollers attached to the side of
the vessel. In the Drawings I have exhibited both points and rollers, but my
meaning is that the one or the other of them only should be employed. To the
lower end of the frame is attached one edge of the paddle board, by means of
links or hinges of an 5 form, so that it may swing freely. When a wheel so
adjusted is at rest, and no means are used to restrain the paddles, they will
bang in a right line with their frames, but a gentle movement of the wheel
will alter the relative positions of the frames and paddles. The frames will
then be in advance of the paddles; but increase this motion, so that the
periphery of the wheel shall move at the rate of three miles per hour, or
thereabouts, and the effect will in part continue the same, and in part be
reversed. From an inspection of the Drawing it will be seen that the centri-
fugal force has thrown the highest paddle into a position at right angles with
its frame. Now, let it be supposed that the paddle is brought down into the
water it must in that case enter the water in nearly a perpendicular direction;
and as it must yield to the water, as soon as the two bodies come in contact
the paddle will be consequently in advance of its frame, and so become and
remain a propeller until the forward movement of the vessel is greater than
the horizontal movement of the paddle, when the current pressing behind it
will throw it down, and it will emerge, as shewn in the Drawing, to perform
a new revolution with the like effect. Back action will under this arrangement
be effected by a reverse motion of the main shaft. By giving the needful
strength to the frames, the paddles may be made extremely light, and the
action will be favored in some respects by their being made of a material of a
less specific gravity than water.
The arrangement represented in the Drawings Number 3 is well adopted
for submerged wheels, for, being provided with the moveable eccentric, forward
action may, without reversing the motion of the main shaft, be changed either
on one side or on both sides into back action. The action of the wheel may in
certain cases be assisted by attaching one or more rings to the body of the
wheel and concentric with it, as shewn at O, whose diameter is such as not to
interfere with the revolving frames, and that the vessel being light, and the
centre of the body of the wheel placed above the water, the paddles shall be

page_text: released just as the frame enters the water. Instead of the concentric ring O,
an eccentric ring may be used of such diameter that, when hung upon the
main shaft (which must turn freely within it) between the radial arms of the
body of the wheel, the upper part of the said eccentric ring shall during slow
motion intercept the paddles as they arrive at the apex, and cause them to
descend into the water in a suitable position, while the lower part of the said
eccentric ring may reach nearly down to the upper edge of the lower paddle
frame when in a vertical position. And in all the arrangements herein-before
described, numbered 1, 2, and 3, the frames with their paddles must be so
adjusted that they shall in all positions revolve free from interference with the
other frames and paddles. Under ordinary circumstances the whole strain will
be upon the body of the wheel, and not upon the cranks, the frame governors
causing little or no friction beyond that arising from their own weight and
action.
And having now particularly described the nature of my said Invention,
and the manner in which the same is to be performed, I declare that in the
Drawings hereunto annexed and herein-before described I have not attempted
to exhibit those proportional dimensions which it would be expedient in
practice to adop, because these must depend upon the size of the vessel and
other circumstances; but that I consider any one accustomed to make paddle
wheels must easily, from the said Drawings and explanations, be fully enabled
to carry into effect my said Invention.
And I further declare that the said Drawings are not made to any scale,
nor are they intended for any other purpose than to assist the comprehension,
by shewing the general design and effect of my said Invention, and to enable
any one more readily to understand the nature thereof.
I further declare that I do not claim any of the separate parts hitherto in
use, such as wheels, paddles, or eccentrics, otherwis than in so far as the same
are newly combined together in my said invented improvements.
And, finally, I declare that what I particularly claim as my Invention are
the improved modes of affixing, regulating, and adjusting the paddles or
floats of vessels propelled by steam or other power, represented in the Drawings
hereunto annexed and herein-before described, by which improved modes the
said paddles or floats are made to offer a direct resistance to the water in those
directions only in which such resistance is required, and to present their
surfaces obliquely to the water at all other times and under all other circum-
stances, and by which also the vessel can be brought up, turned, backed,
or otherwise controuled more effectually than is practicable with the common
wheel.

page_text: And such my said invented improvements being, to the best of my know-
ledge and belief, never heretofore used in this country, I declare this to be my
Specification of the same, and that I do verily believe this my said Specification
doth comply in all respects fully and without reserve or disguise with the
proviso in the said herein-before in part recited Letters Patent contained;
wherefore I hereby claim to maintain exclusive right and privilege to my said
Invention.
In witness whereof, I, the said Henry Pickworth, have hereunto set my
hand and seal, this Twenty-sixth day of July, in the year of our Lord
One thousand eight hundred and thirty-six.
Inrolled the Twenty-sixth day of July, in the year of our Lord One
thousand cight hundred and thirty-six.