IMPROVEMENTS IN THE METHOD OF PROPELLING VESSELS THROUGH WATER
Year: 1841

page_text: BOOTH, of Liverpool, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Sixteenth day of December, in the fifth year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said Henry
Booth, Her especial licence, full power, sole privilege and authority, that I,
the said Henry Booth, my executors, administrators, and assigns, or such
others as I, the said Henry Booth, my executors, administrators, or assigns,
should 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, excrcise, and vend, within England, Wales, and the Town
of Berwick-upon-Tweed, my Invention of "IMPROVEMENTS IN THE METHOD OF
PROPELLING VESSELS THROUGH WATER;" in which said Letters Patent is con-
tained a proviso that I, the said Henry Booth, shall cause a particular descrip-
tion of the nature of my said Invention, and in what manner the same is to
be performed, to be inrolled in Her said 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 there-
unto had, will more fully and at large appear.
NOW KNOW YE, that the nature of my Invention, and the mode of
carrying it into operation, may be described as follows:-
The principle of my Invention consists in a concentration of nearly the
whole force of the engine or moving power into one-tenth or other small

page_text: portion of each stroke of the piston; and I make use of such concentrated
force to effect a proportionably powerful stroke with the propellers, the
momentum of the vessel so gained carrying it onwards through the water till
the next stroke; and the mechanical arrangements and implements which I
employ to carry into effect this principle, and the mode of operation, I will
now describe. I shall not specify any particulars of the engine, because I
claim no novelty in the moving power, but only in the propellers-in the
mechanical arrangements and implements by means of which the propellers
are worked, and the principle I have explained carried into effect, the moving
beam or beams (B), through which the power is communicated, being worked
by an engine or engines in the ordinary or most approved way.
C1 & 2, Figure 1, are cam wheels, which I employ to communicate the
power of the engine to an upright lever L, vibrating on its axis (A) at its
foot, and connected at the top by rod and crank with the main shaft S, to
which the propellers are attached. The crank or short lever thus fixed to the
main shaft, inside of the vessel, corresponds in its movements with the pro-
pellers. Fixed to the same shaft, outside the vessel P, is the propeller, one
on each side of the vessel, serving instead of the ordinary paddle-wheel; the
portion of it to which the water offers resistance, and by means of which the
vessel is propelled, consisting of a valve plate (V) working on hinges like a
valve or door kept closed by a moveable cross bar when forced in the direction
required to propel the vessel, and on the return motion opening on its hinge
or axis, and yielding to the water, so as to offer little or no resistance, the
movement of the propeller or single paddle being vibratory backwards and
forwards, instead of the rotary movement of the ordinary paddle-wheel. It
will be perceived that when the working beam is in motion, and the cam
wheel No. 1 is made to revolve in the direction indicated by the arrow, the
cam, which occupies about one-tenth part of the wheel's circumference, and
which is shaded dark in the Drawing, communicates motion to the upright
lever L, through the friction wheel F, which moves between and receives its
motion from the two cam wheels, and thus causes motion to the crank and
main shaft, and consequently to the propellers. The forward or principal
motion is effected in about one-tenth portion of the whole revolution of the
cam wheels (or double stroke of the piston), the cam of wheel No. 1 occu-
pying about one-tenth of the periphery of the cam wheel, while the return
motion of the lever L, bringing back the propellers with the valves or leaves
open, (I, Figure 2,) is effected slowly by means of the extended cam on the
wheel No. 2, also shaded dark, which moves in the same direction, as indi-
This clougated cam (No. 2) comes into operation
cated also by the arrows.
.

page_text: when the other cam ceases to act, and occupies about nine-tenths of the peri-
phery of the wheel No. 2. The return motion, therefore, of the lever L, and
consequently of the propellers, is about nine times slower than the primary
motion effected by the can of the wheel No. 1, the engine working equally
throughout. The upper end of tho lever L, we have stated, is connected with
the main crank, (M, C,) which is attached to the main shaft (S), and moves
simultaneously and in the same direction as the propellers, constituting
mechanically a lever of the third class. But, the crank being only four feet
in length to a propeller of 20 or 24 feet radius, the velocity of the extreme
end of the propeller, namely, of the closed valve plate or paddle-board (V) is
proportionably more rapid, and, being also a great depth below the surface of
the water, the effectiveness of the propeller is multiplied in a greatly increased
ratio. Now, the mode of operation is as follows in the forward or ordinary
movement of the engine:-The cam wheels 1 & 2 are moved round in the
same direction by cranks and connecting rods, communicating with the reci-
procating beam in the ordinary way, regulated by the slow uniform speed of
the engine piston, which I will suppose 2½ miles per hour. The dimensions
of the engine cam wheels, levers, &c. must obviously vary with the size of the
vessel and other circumstances. In this Specification I suppose the engine or
engines to have a five-feet stroke, the cam wheels to be 10 feet diameter, each
making one revolution with cach double stroke of the engine. The cam
attached to the periphery of the wheel No. 1, in the forward movement,
extends along 3 feet of the circumference, (about 16th of the whole,) and
projects 15 inches from the circumference in its extreme action, which is con-
sequently the extent of motion communicated to that point of the lever L
which forms the centre or axis of the friction wheel F. This point is half way
between the pivat or axis A, on which the upright lever rests and vibrates,
and the upper end E; consequently, the upper end E moves 2 feet 6 inches,
while the cam communicates a motion of one foot 3 inches to the centre of
the vibrating lever. The upper end of the lover, being connected with the
main crank M, C, communicates to it a 2 feet 6 inches vibrating a bell-crank
motion. This crank or short lever I suppose 4 feet long, and attached to
the main shaft, to which the propellers also are attached (one on each side
the vessel); and the propellers I suppose to be 20 feet long from the main
shaft to the centre of the valve plates or paddle-boards, or 5 times the length
of the main crank (10 feet from the shaft to the water, and 10 feet deep in the
water. Sec Figure 2.) The paddles, or valve plates, therefore, will make a
stroke of 12 feet, while the crank end moves 2 feet 6 inches in the same
direction. Now, this movement or stroke of 12 feet in the water is effected

page_text: while the cam wheel No. 1 moves one-tenth part of a revolution or that
portion of the revolution which completes the action of the cam No. 1 against
the upright lever L in the forward movement of the engine; consequently,
the propelling stroke of 12 fect in the water is effected while the engine
piston moves one foot, or one-tenth part of a double stroke. If the piston,
therefore, moves at the rate of two miles and a half an hour, the propeller will
move through the water at the rate of 2×12 or 31 miles an hour; the
increase of speed being effected by the quiet and smooth motion of the levers,
the centre or bearing point of the upright lever L moving only 1 foot 3 inches
in each direction with each double stroke of the piston. The speed of the
propelling valve plate is here stated at 31 miles p hour; but it is obvious
that this may be varied by varying the size and projection of the cam or the
proportion of the levers or cranks, or by modifying the sweep of the cam.
The velocity of the propeller may commence at 12 or 14 miles an hour,
(a little below the supposed speed of the vessel, and therefore producing no
shock,) and gradually increase to 30 or 35 miles, and then diminish down
to 15 or 20 an hour before the end of the stroke. Still further to render
smooth the motion of the propeller, two or moro springs are placed on each
side of the valve plate to render the shutting action of the plate against the
supporting cross bar smooth and gradual, the springs assisting the opening of
the valve plate on the return motion of the propeller. Thus every thing like
shock or percussion in the action of the propeller is
smooth and nearly uniform motion imparted to the vessel.
that the propelling movement is accomplished in about
the cam wheel, or 'oth of a stroke of the engine piston, the duty of the
engine during the remaining ths of the stroke being to bring back, by means
of the elongated cam No. 2, at a slow speed, the propeller with open valve, to
keep up the momentum of the heavy cam wheels, and quietly to raise the
piston of the pneumatic cylinder Q, which by its descent is to assist the prin-
ciple movement or rapid stroke of the propeller.
to be avoided, and a
It is thus evident
th of a revolution of
The action of this pucumatic engine or reserved power, by means of a
vacuum and compressed air, I shall now describe. Qis the pneumatic
cylinder closed at each end. The stroke of the piston will be to the same
extent as the motion of the upper end of the upright lever L, to which the
piston is attached by a chain and wheel, as shewn in Figure 1, or other
efficient mode of connexion. The reserve power is brought into action as
follows-The cylinder Q is to be filled with air more or less compressed
by a small force pump. If the stroke of the pneumatic is 2 ft. 6 in. the
length of the cylinder space should be 5 feet. When the piston is at the

page_text: bottom, the air must be forced into the cylinder to the density, I will.suppose,
of 100 lb. p square inch, the exact amount of compression to be at the
option of the engineer). As the cam wheel No. 2 moves the propellers slowly
back, with the valve plates open, the pneumatic piston will be slowly raised;
and when the stroke is finished, the area above the piston will be diminished
one-half, and the density of the compressed air will consequently be double, or
200 lb. p inch, which, on the return of the upright lever L, will powerfully
assist the steam engine or principal moving power in effecting the forward or
main stroke of the propeller. If found desirable, a small portion of air
may be admitted underneath the pneumatic piston, which, being compressed
on its descent, will act as an air cushion to prevent any shock at the end of
the stroke. The diameter of the pneumatic cylinder, as well as well as the
degree of compression on the air, must be left to the judgment of the con-
structing engineers. In the Drawing (Figure 1) the cam of the wheel 1 is
represented in the position of having just completed its action on the lever L
and propeller P in the principal movement, propelling the vessel forward, and
the cam of wheel 2 just about to commence the slow backward movement by
which the reserved power is raised, and the levers and propellers quietly
brought back and placed in position for the next effective stroke.
In Figure 2 are separate Drawings of the propeller, showing the action of
the valve plate and the mode in which it may be thrown out of gear or put
into back gear either on one side or both sides of the vessel, or it may be
thrown out of gear on one side and continued in gear on the other side, or
be put in back gear on one side and forward gear on the other side, when it
is wanted to bring the vessel quickly round, the utility of all which operations
will be obvious to nautical men. H, Figure 2, is a front view of the propeller
with the valve plate closed (v), the lower edge supported by the sliding
cross bar O. This bar has a capacity of motion up and down of a few inches
effected by a lever and small crank on deck, attached to the bar by two con-
necting rods r,r. When it is lowered down, the valve plate is loose, and will move
backwards and forwards on its hinge or axis (A), having no power to propell the
vessel either backwards or forwards; but when the bar is raised, as at H, the
lower edge of the valve plate is forced by the water against the cross bar (0),
and the propeller comes into action; and it is evident that, according as this
sliding bar is raised at the front or back of the moveable valve plate the pro-
peller will become efficient to move the vessel either forwards or backwards,
which may be done in a second of time, at the option of the engineer, on one
side the vessel or both, and either with or without reversing the engine. K
is a side view of the propeller, showing the moveable bar and connecting rod

page_text: guided in a slot behind the bottom of the valve plate, the connecting rod (1)
extending up to the deck where it is worked by the lever (i) and small crank,
as before explained, being lowered a few inches, when required, to throw the
valve plate out of gear, or to allow the valve plate to pass to the opposite side
of the cross bar, and so become efficient to move the vessel in the opposite
direction. I (Figure 2) is a side view of the propeller with the valve plate
open and nearly invisible, the edge of it only being scen. Now, the material
and the mechanical structure of the propeller may be left in some degree to
the engineer who contrives and arranges the machinery, the size and strength
being proportioned to the size of the vessel and power of the engine. The
propeller may be considered as somewhat resembling a single arm or spoke of
a large paddle wheel, except that it must be made much stronger, as it will be
subjected to greater strain, the valve plates having to sustain a greater resist-
ance than the boards or floats of the paddle wheel, owing to their being deeper
in the water, and the principal movement being quicker. I recommend two
strong plates of rolled or forged iron with sharp edges to cut through the
water, as the proper material for the sides or arms of the propeller, between
which the valve plates are to act, the said sides being at the upper end bolted
to cast-iron discs (d) keyed firm on the main shaft, as shown in the plan and
perspective view, and at the lower end fastened together and kept parallel by
a cross plate bolted to the sides or arms below the valve plate, presenting, when
in motion, sharp edges to the water. The valve plates working on their axis
between the sides of the propeller may be made of plate steel with spring plates
on each side S to prevent any violent concussion between the valve plate and
the supporting cross bar.
As witness my hand and seal, the Eleventh day of June, One thousand
eight hundred and forty-two.
HENRY BOOTH. (L.S.)
Signed, sealed, and acknowledged by the said
Henry Booth, this 11th June 1842, before
HENRY BEAUSIRE.
Inselled the Sixteenth day of June in the year above written.