IMPROVEMENTS IN PROPELLING SHIPS AND OTHER FLOATING BODIES
Year: 1852

page_text: LETTERS PATENT to William Taylor, residing at No. 16, Oxford
Terrace, Hyde Park, London, for the Invention for "IMPROVE-
Scaled the 29th January 1853, and dated the 2nd December 1852.
PROVISIONAL SPECIFICATION left by the said William Taylor
at the Office of the Commissioners of Patents, with his Peti-
tion, on the 2nd December 1852.
I, WILLIAM TAYLOR, residing at 16, Oxford Terrace, Hyde Park,
London, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN PROPELLING SHIPS AND OTHER FLOATING BODIES" to be
as follows:-
It will conduce to a clear apprehension of the nature and value
of my Invention to prefix to a statement of it a case from gunnery.
Suppose a 24 pounder, the ball of which weighs 24 lb., and that
this ball is propelled by the force of the elastic gas generated by
the combustion of the gunpowder, with an initial velocity of 1650
feet per second, then the momentum of this ball, or the amount of
the action, will be 1650 multiplied by 24, or 39,600. Let us sup-
pose the weight of the gun and carriage to be 300 times the weight
of the ball, or 7200 lb.; then as the reaction of the gun and
carriage, or moment, must necessarily be equal to the action or
moment of the ball, the initial velocity with which the gun &

page_text: carriage is propelled, must be 2000 or 5 feet per second, but the
relative quantities of the expansive force of the elastic gas expended
on the ball and on the gun & carriage, are determined, not by
multiplying the weights into the initial velocities, but the weights
into the squares of the initial velocities. In the given case, the
quantity expended on the ball will be represented by 24 multiplied
into the square of 1650, or into 272,500, & will amount to
65,340,000; and the quantity expended on the gun & carriage, to
7200 multiplied into the square of 5, or into 30-35, amounting to
218,520, from which it appears that the quantity of the expansive
force of the gas expended on the ball is 299 times, or nearly 300
times, that expended on the gun and carriage; and that it is so is
proved by experience, for the charges of gun powder are propor-
tional, not to the initial velocities of the ball, but to the squares of
those initial velocities; and further, the penetrations of the ball into
timber are proportional, not to the velocities, but to the squares of
those velocities; and as the effect, that is, the penetration, is propor-
tional to the squares of the velocities, it necessarily follows that the
cause which produced that effect, namely, the amount of the expan-
sive force expended in producing the effect, must be proportional to
the squares of the velocities.
Now, in the propulsion of floating bodies, the ship or floating
body corresponds to the ball. It is the projectile, and the water
which is struck and recoils corresponds to the gun and carriage.
Hence it is obvious how important it is that, (even supposing the
action, that is, the initial velocity, generated in the ship in a second,
by a single revolution of the screw, or the single impulse of any
other propeller, multiplied into the weight of the ship, to remain
unaltered, and the reaction or the velocity generated in the water
struck in a second by the same single impulse multiplied into the
weight of the water struck, which must necessarily be equal to the
action, remaining unaltered,) in order that the least possible, quan-
tity of the force of the steam, and of course of the horse power and
coal, be expended on the propeller, the weight of the water struck
should be as great as possible, and the initial velocity of it should

page_text: be as small as possible. Now, precisely the opposite of this takes
place in the Screw Propeller. The quantity of water put in motion
may be supposed proportional to the number of square feet struck
by the screw, and this quantity is extreinely small, while the initial
velocity which may be supposed proportional to the velocity of the
screw is very great, and consequently the greater part of the horse
power of the engine or of any other power employed as the motive
force is expended on the recoiling body, and not, as in the case of
the 24 pounder, on the projectile.
Now, the object of my Invention is to effect that the reaction be
composed, not of a small weight and a great velocity, but of a great
weight and a small velocity, by means of which I diminish the
quantity of steam or other power expended on the recoiling mass;
and this object I attain in the following manner: -
I cause one, or two or more, wedge-shaped or truncated wedge-
shaped, or approximately wedge-shaped or truncated wedge-shaped
bodies, the vertical longitudinal plane in which the axis of which
when in the middle of their vibrations, is situated is parallel to the
plane in which the longitudinal vertical midship section of the ship
is situated, to vibrate round a hypomoclion connected by a rigid
body with the ship in such manner that if the edges of the angle
which the wedge forms at the point are produced to the distance of
the hypomoclion, and then joined by a straight line and lines drawn
parallel to the axis when in the middle of the vibration; from the ex-
tremities of this line, the vibrations shall not pass beyond those
parallel lines; for example, in Fig. 1, let the wedge or approximate
wedge be A D TE B, and the angle FT G, producing the edges
D T, and E T; to F, and G, at the distance of the hypomoclion H,
the produced edges will be distant from each other (at the distance
of the hypomoclion from the point) F G. Then drawing the dotted
lines F I, and G K, parallel to the axis HT, and to each other; the
vibrations of the wedge must not pass beyond those dotted parallel
lines; then the wedge will always strike the water after decomposi-
tion of the motion in the direction L, and of course the hypomoclion
and the ship with which it is connected will be impelled in the di-

page_text: rection M; and if there be two wedges at work, one on each side of
the ship, and their outward stroke and inward stroke be simul-
taneous in each, the ship will be propelled in the direction of the
keel. And this I am the better enabled to accomplish, from the
existence of a fact determined by experience, namely, that sup-
posing the line OP (Fig. 2), to represent the horisontal section
of a board one foot square and an inch thick, & that the resist-
ance to that board pushed thro' the water with a given velocity,
or the impulse of a stream of water moving against it with a given
velocity (it is immaterial which), is equal to 10,000, and that two
opposite edges of this board are joined by other boards so as to form
a prow or angular projection as in Fig. 3, & 4, at the respective angles
of. 60°, 48°, 36°, 24°, and 12°, the resistance to the motion, or the
reaction will be 4404, 4240, 4142, 4063, & 4000, and as the quantity
of the resistance or reaction at 12° is still 4-10ths of the original
reaction, and has diminished little from 24° to 12°, there is reason to
believe that even at a much less angle than 12° it still continues
nearly 4-10ths. But as the quantity of the reaction is made up of
the weight multiplied into the initial velocity, and as the weight or
quantity of water struck increases as the wedge becomes longer
and the angle at its extremities smaller, it follows necessarily that
the velocity of the water struck must diminish, in order that the
quotients of the mass put in movement multiplied into the initial
velocity communicated to it, which quotient composes the reaction,
may remain the same.
To illustrate the importance of this arrangement, supposing
a screw to strike 40 square feet with a velocity of 35 feet per
second, its action will be 1400 ; & supposing two wedge pro-
pellers to strike jointly 700 square feet with a velocity of 2 feet
per second, & that the loss sustained by the obliquity of the stroke
is equal in the cases of the screw & the wedges, the reaction of
the wedges will also be 1400; but the relative quantities of the
power expended will be as 40 × 352 to 700 × 22, or as 49000 to 2800,
or as 171 to 1

page_text: SPECIFICATION in pursuance of the conditions of the Letters
Patent, filed by the said William Taylor in the Great Seal
Patent Office on the 19th April 1853.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
WILLIAM TAYLOR, residing at No. 16, Oxford Terrace, Hyde Park,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Second day of December, in the
year of our Lord One thousand eight hundred and fifty-two, in the
sixteenth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said William Taylor, Her
special licence that I, the said William Taylor, my executors,
administrators, and assigns, or such others as I, the said William
Taylor, 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 "PROPELLING SHIPS AND OTHER FLOATING
BODIES," upon the condition (amongst others) that I, the said William
Taylor, by an instrument in writing under my hand and seal, should
particularly describe and ascertain the nature of the said Inven-
tion, and in what manner the same was to be performed, and cause
the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said William Taylor, do hereby
declare the nature of my said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained
in and by the following statement, (that is to say):
of
It will conduce to a clear apprehension of the nature and value
my Invention to prefix to a statement of it a case from gunnery.
Suppose a 24 pounder, the ball of which weighs 24 lb., and that
this ball is propelled by the force of the elastic gas generated by

page_text: the combustion of the gunpowder, with the initial velocity of 1650
feet per second, then the moment of this ball, or the amount of the
action, will be 1650 multiplied by 24 or 39,600. Let us suppose
the weight of the gun and carriage to be 300 times the weight of
the ball, or 7200 lb., then as the reaction or moment of the gun
and carriage must necessarily be equal to the action or moment of
the ball, the initial velocity with which the gun and carriage is pro-
pelled must be 2009 or 5 feet per second; but the relative quan-
titics of the expansive force of the elastic gas expended on the ball
and on the gun and carriage, are determined, not by multiplying
the weights into the initial velocities, but the weights into the
squares of the initial velocities. In the given case, the quantity
expended on the ball will be represented by 24 multiplied into the
square of 1650, or into 272,500, and will amount to 65,340,000,
and the quantity expended on the gun and carriage to 7200 multi-
plied into the square of 5, or into 30.35, amounting to 218,520;
from which it appears that the quantity of the expansive force of
the gas expended on the ball is 299 times, or nearly 300 times, that
expended on the gun and carriage; and that it is so is proved by
experience, for the charges of powder are proportional, not to the
initial velocities of the ball but to the squares of those velocities;
and further, the penetrations of the ball into timber are proportional,
not to the velocities, but to the squares of those velocitics; and as
the effect, that is, the penetration, is proportional to the squares of
the velocities, it necessarily follows that the cause which produces
that effect, namely, the amount of the expansive force expended in
producing the effect, must be proportional to the squares of the
velocities.
Now, in the propulsion of floating bodies, the ship or floating
body corresponds to the ball. It is the projectile, and the water
which is struck and recoils corresponds to the gun and carriage.
Hence it is obvious how important it is that (even supposing the
action, that is, the initial velocity generated in the ship in a second
by a single revolution of the screw, or the single impulse of any
other propeller, multiplied into the weight of the ship, to remain

page_text: unaltered, and the reaction or the velocity generated in the water
struck multiplied into the weight of the water struck, which must
necessarily be equal to the action, to remain unaltered,) in order
that the greatest possible quantity of the force of the steam, and of
course of the horse power and coal, be expended on the propeller,
the weight of the water struck should be as great as possible, and
the initial velocity of it should be as small as possible. But pre-
cisely the opposite of this takes place in the screw propeller. The
quantity of water put in motion, may be supposed to be proportional
to the number of square feet struck by the screw, and this quantity
is very small, while the initial velocity which may be supposed pro-
portional to the velocity of the screw is very great, and consequently
the greater part of the horse power of the engine, or of any other
power employed as the motive force, is expended on the recoiling
mass, and not, as in the case of the 24 pounder, on the projectile.
Now, the object of my Invention is to effect that the reaction be
composed, not of a small weight and a great velocity, but of a great
weight and a small velocity, by means of which I diminish the
quantity of steam or other power expended on the recoiling mass;
and this object I attain in the following manner: —
I cause one, two, or more wedge-shaped or truncated wedge-shaped,
or approximately wedge-shaped or truncated wedge-shaped body or
bodies, the axis or axes of which when in the middle of its oscilla-
tion or their oscillations is or are situated in a plane parallel to the
plane in which the vertical longitudinal midship section of the ship
is situated, to oscillate round a hypomoclion connected by a rigid
body with the ship in such manner that if the edges of the angle
which the wedge forms at the point are prolonged to the distance
of the hypomoclion, and then joined by a straight line and lines
drawn parallel to the axis when in the middle of the oscillation;
from the extremities of this straight line the oscillations shall not
pass beyond those parallel lines; for example, in Fig. 1, let the
wedge or approximate wedge be AD TE B, and the angle FT G,
producing the edges DT; and E T, to F and G, at the distance
of the hypomoclion, the produced edges will be distant from each

page_text: other by the extent of the line FG. Then drawing the dotted lines
FI, and GK, parallel to the axis H T, the oscillations of the
wedge must not pass beyond those parallel lines; then the wedge
will always strike the water after decomposition of the motion in
the direction L; and of course the hypomoclion and the ship with
which it is connected will be impelled in the direction M; and if
there be two wedges at work, one on each side of the ship, and their
outward stroke and inward stroke be simultaneous in each, the ship
will be propelled in the direction of the keel. And this I am the
better enabled to accomplish from the existence of a fact deter-
mined by experience, namely, that supposing the line O P, in
Fig. 2, to represent the horisontal section of a board one foot square
and one inch thick, and that the resistance to that board pushed thro'
the water with a given velocity, or the impulse of a stream of water
moving against it with a given velocity (it is immaterial which), is
equal to 10,000; and that two opposite sides of this board are joined
by other boards, so as to form a prow or projection, as in Figs. 3,
and 4, at the respective angles of 60°, 48°, 36°, 24°, and 12°, the re-
sistance to the motion or the reaction will be 4404, 4240, 4142, 4063,
and 4000; and as the quantity of the resistance or the reaction at
12° is still 4-10ths of the original reaction, and has diminished little
from 24° to 12°, there is reason to believe that even at a much lesser
angle, it will still continue nearly 4-10ths. But as the quantity of
the reaction is made up by the quantity of the weight multiplied
by or into the initial velocity, and as the quantity of the weight or
quantity of water struck increases as the wedge becomes longer
and the angle at its extremity smaller, it follows necessarily that
the velocity of the water struck must diminish, in order that the
quantity of the mass put in motion, multiplied into the initial
velocity communicated to it which quotient composes the reaction,
may remain the same.
To illustrate the importance of this arrangement, supposing a
screw to strike 40 square feet with a velocity of 35 feet per second,
its reaction will be 1400; and supposing two wedge propellers to
strike jointly 700 square feet with a velocity of 2 feet per second,

page_text: and that the loss sustained by the obliquity of the stroke is equal
in the case of the screw and wedges, the reaction of the wedges will
also be 1400; but the relative quantities of the power expended will
be 40 x 352 to 700 × 22, or as 49,000 to 2800, or as 17 to 1. This
illustration, however, which was presented in the Provisional Specifi-
cation shortly and loosely merely for the purpose of elucidating the
previous introductory matter, does not contain several of the
grounds for calculation which must be comprised in order to arrive
at an accurate comparative view. Among other corrections the ratio
must be diminished, because the projection of the striking surface of
the wedge on a plane perpendicular to the direction in which the
motion is to be estimated, and the angle of incidence of this surface
on the fluid, vary during the oscillation, and because the mean of
this varying angle is less than the constant angle of incidence of the
striking surface of the screw blade; and it must be increased, and
that
very greatly, because the effect, and consequently the quantity
of motive power expended in producing that effect, in the case of
surfaces revolving in the manner of vanes of a windmill or blades
of a screw propeller, is nearly but somewhat less than as the cube
of the velocity. But after a full examination of all the attendant
circumstances, the final result of the inquiry would exhibit a high
ratio between the expenditures requisite to generate the same pro-
gressive motion of the ship.
I now describe a particular manner in which the said Invention
may be performed. Fig. 5, represents one half of that part of
the largest vertical and athwart section of an 80 gun ship in frame
(and of course without planking), which is situated below the load
water line. W L, 1, indicates the load water line. W L, 2, the water
line corresponding to the least depth of the propeller. WL, 3, to the
middle line. W L, 4, to the greatest depth of the propeller; on the
side of this one half section is represented a vertical and transverse
section of that part of the propeller which is opposite to this section
of the ship, and corresponds to the dotted lines a b, a b, in Figs.
6, and 7, shewing further its distance from the ship. Fig. 6, is
an elevation of that part of the same ship, which is also supposed
to be in frame (and of course without planking, rudder-gripe, or

page_text: cutwater), situated below the load water line, and also of the pro-
peller, which, it will be observed, extends nearly the whole length of
the ship, but the vertical height of it diminishes as it approaches
the stem, in order to diminish the quantity of matter without a pro-
portional diminution of the of the propulsive effect. The propeller is
represented connected with the propeller prow, and oscillating on a
hinge on the propeller prow is indicated the tenon of the junction
timber, which is mortised into the propeller prow, and fixed by a bolt.
Fig. 7, represents one half of a horisontal section of the same ship
at the water line W L, 3, the ship being also supposed to be in frame
and without planking, except for a short distance towards the stem,
where the planking is superadded. The junction timber is attached
to the stem and adjoining parts of the ship, by three dowels and
three bolts, and additionally by a diagonal stay fixed by three bolts
to frames of the ship. The propeller is twice made to diminish in
breadth, for the same reason that in Fig. 6, it is made to diminish
in height. Motion is given to the propeller (thro' the inter-
medium of a sway rod fixed to the propeller by four bolts passing
thro' a stuffing box inserted in a frame of the ship, and oscilla-
ting in the arc of a circle of great radius), by the connecting rod of
a steam engine working expansively, the cylinder of which is hori-
sonal, the length of stroke three fect nine inches, and the power
125 horse real power.
The propeller is formed of timber connected in the usual manner
by scarphs, dowels, and bolts, and so adjusted that the whole, after
being sheathed with copper, is nearly of the same weight as the bulk
of the fluid which it displaces. The part nearest the point is
formed exclusively of Malabar teak.
Altho' the propeller, considered by itself, has neither tendency to
sink nor to rise, it is necessary to make some provision against the
resistance of the inertia of the matter of which it is composed
when the ship rolls. For this purpose a supporting timber is used,
which is round at one extremity and passes thro' a round aper-
ture in the propeller, both that part of the supporting timber upon
which the propeller oscillates and the aperture being sheathed with

page_text: brass; on entering the ship the transverse vertical section becomes
rectangular. On its entrance into the ship it rests on a thick
planking in nature of a shelf, extending to three frames, to which it
is doweld and bolted, the shelf being also doweld and bolted to the
frames, and to prevent its rising a similar planking above, similarly
fixed to it and the frames, is adjusted. The other end rests on a
step laid on the kelson and secured by a bolt, which passes thro'
supporting timber, step, kelson, floor timber, and keel. Of course
there is a similar arrangement on the starboard side of the ship.
Fig. 8, is a transverse vertical section of the propeller at the dotted
Fig. 9,
line n o, in Fig. 6, & 7.
line lm, in
Fig. 6, & 7.
at the dotted
In conclusion, I claim as my Invention generally, such disposition
or arrangement of such body or bodies so moving, and so connected
with the ship or floating body, as is already previously generally
described, beginning with the words, "I cause one or two," and
ending with the words, "direction of the keel."
In witness whereof, I, the said William Taylor, have heretoforc
set my hand and seal, this Nineteenth day of April, in the
year of our Lord One thousand eight hundred and fifty-
three.