CERTAIN MEANS OP PRODUCING A COMMUNICATING MOTION IN OR UNTO BODIES EITHER WHOLLY OR IN PART SURROUNDED BY WATER OR AIR, OR EITHER OF THEM, BY THE REACTION OF SUITABLE APPARATUS UPON THE SAID WATER OR AIR, OR UPON BOTH OF THEM
Year: 1814

page_text: DAWSON'S SPECIFICATION.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
DAWSON, of York Street, in the City of Dublin, Esq., send greeting.
WHEREAS His most Excellent Majesty King George the Third, did,
by His Letters Patent under the Great Seal of the United Kingdom of
Great Britain and Ireland, bearing date at Westminster, the Sixteenth day of
July, in the fifty-fourth year of His reign, give and grant unto me, the said
James Dawson, my exors, adññors, and assigns, His especial licence, full power,
sole privilege and authority, that I, the said James Dawson, my exors,
adiñiors, and assigns, during the term of years therein mentioned, should
and lawfully might make, use, exercise, and vend, within England, Wales,
and the Town of Berwick-upon-Tweed, my Invention of "CERTAIN MEANS
OP PRODUCING A COMMUNICATING MOTION IN OR UNTO BODIES EITHER WHOLLY OR IN
PART SURROUNDED BY WATER OR AIR, OR EITHER OF THEM, BY THE REACTION OF
SUITABLE APPARATUS UPON THE SAID WATER OR AIR, OR UPON BOTH OF THEM;" in
which said Letters Patent there is contained a proviso obliging me, the said
James Dawson, by an instrument in writing, under my hand and seal, to
cause a particular description of the nature of my said Invention, and in what
manner the same is to be performed, to be inrolled in His Majesty's High
Court of Chancery within twelve calendar months next and immediately
after the date of the said recited. Letters Patent, as in and by the same,
(relation being thereunto had, may more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
James Dawson, do hereby declare that the following is a full and particular
description of the means I use to produce and communicate motion to boats,
ships, and other vessels, by means of certain oars or levers, which I call

page_text: reciprocating or rotatory propellers, or by inclined planes of various forms and
constructions; and the same are more fully elucidated and described by the
Drawings hereunto annexed; and I do cause the same to be put in motion
by the power of men or the steam engine, or other suitable first mover, by
due connection therewith, and in general I do fix the arms or levers of the said
propellers on the outside or external part of the said vessels which I intend to
move, and place them at right. angles thereto, or nearly. so, in order that the
remoter extremity, which is immersed in the water or other fluid may act in the
most effectual manner; but I do also use and apply my said propellers herein
described at other angles, or horizontally, as choice or convenience may require.
Figure 1, No. 1, is a wheel consisting of two or more arms turning on pivots
at right angles to each other, with floats or boards fixed thereon, and the said
arms have pallets of the form shewn attached thereto, (which may be made to
revolve either within or without the nave,) and I fix a projecting piece, as shewn
in Figure 1, No. 2, to the side of the vessel, through the centre of which the shaft
or arbor of the wheel passes. As the wheel revolves the several palletts succes-
sively strike against the projecting arc a, which causes the arm and paddle to
make a quarter revolution on its centre; each paddle is thus made to enter the
water on its edge, and is turned to its full surface therein, and retains that posi-
tion till it passes beyond the centre of the wheel, when it is again gradually
turned and rises out of the water on its edge. By drawing in or protending
the projecting arc Figure 1, No. 2, any degree obliquity may be given to the
paddles in revolving, and by their diagonal action on the water the vessel may
be occasionally steered by one or both wheels. The several arms may be made
to revolve in a shrouding, and one or more of the paddles may be made to shift
or take out, in which case the vessel can be sailed in the usual way. The
paddle, instead of being formed of one piece, may be made of several pieces con-
nected together in a frame, and feathered as before described by pallets. If the
paddles and their pallets are posited at right angles to each other on the same
arm, the effect will be, that at the same instant, the one presents its full surface,
the other will present its edge. Figure 2 represents the front view of a similar
wheel, with fixed shrouding boards, a, a, a. The paddles are made to change
their position as they enter and leave the water, as before described in the first
wheel. Fig. 3 represents a wheel with three radii, and with fixed shrouding
boards as in the last Figure. The paddles in this Figure are made to open and
shut as they enter and leave the water, owing to the projecting pieces being
placed on both sides of the nave of the wheel. The pallets are made to move
back and forward. Figure 4 represents a wheel, the paddles of which are fixed
upon arms to turning-on pivots, and the said paddles are placed so as to cause
.L

page_text: the surfaces on each side of the arm to be unequal, and so adjusted by stops
that the action of the water closes them on entering therein, and opens them
on rising thereout. Figure 5 is a deep shrouded wheel; the float boards are con-
nected by hinges to the arms with a stop fixed thereon. The arms are placed
off the centre of the wheel as shewn, to avoid the lift of water; with a similar
intention I construct wheels with float boards proceeding in a direct line from the
square of the shaft; and likewise, in some cases, I cause them to proceed
diagonally from a smaller internal circle, forming a tangent therewith. Figure
6 represents a wheel formed of one, two, or more paddles placed obliquely and
successively within each other, leaving an opening in the middle to ease the
action of entering and leaving the water. Figure 7 represents a wheel, the
paddles of which are formed by placing two boards at a suitable angle,
leaving an opening between them of a proper breadth, and about one half of
their length, through which, as the paddles enter, the water will freely escape,
and when they arrive in their descent at an angle of forty-five degrees, they
are to encounter a board of the dimension of the aperture fixed to the side of
the vessel, which will fill up the aforesaid aperture, untill they pass beyond a
vertical position, when the water will again escape. Figure 8 represents a wheel,
the several paddles of which may be formed of elastic or non-elastic materials,
and made to describe arcs of circles, as shewn when in action; and on the back
of the outer paddle I sometimes place a board, like a tongue or feather, as
shewn by the dotted lines (a, b,) and I occasionally continue the secondary
paddles to the outer edge of the shrouding, as represented by the dotted lines
(c, d); when more than one curved paddleis used, openings should be left in the
shrouding between them. Fig. 9 represents a wheel, which differs somewhat
from the foregoing, by the continuity of the sweep being broken at (a), and there
met by another proceeding from the centre of the wheel. And further, I do
construct wheels the paddles of which are made to describe parabolic curves,
either by giving to them that form in the first instance, or by constructing and
forming them of materials of such a degree of elasticity and flexibility that
the action of the water will cause them to assume such curves when revolving
with a given velocity; and I do consider the adoption and use of flexible
and elastic materials in the general construction of the paddles of my wheels,
oars, or propelling apparatus, as forming a peculiar feature of my Invention.
The relative proportions of the paddles to the diameter of the wheel, and
their number and curvature are to be varied according to the manner and
the uses to which the same may be applied. In some cases, in addition
to wheels, I apply a water screw or screws of a suitable angle and size, by
placing one or more of them through the centre of the vessel from stem to

page_text: stern in a hollow way or open space made to receive them, and I connect
them with the first mover by inclined planes, wheels, and worms, and I do
place the said water screws occasionally under the vessel, or at the sides, posited
either horizontally or at a given angle, and in some cases only a portion of
the said water screw may be immersed in the water, and if a rapid motion be
given to the said worm or screw, a quantity of air will be forced through the
water. Fig. 10 shews the manner in which two or more flexible or inflexible,
angular or triangular paddles may be worked at once on each side of the
vessel, by fixing one end of an horizontal bar D upon a pin projecting near the
circumference of the wheel A, which may be fixed upon the axis of the first
mover, and attaching the other end of it to a similar wheel C. To this
horizontal bar I firmly fix the handle or lever of the paddle, and by communi-
cating the motion to a second wheel B, by means of a band or chain or other.
well known contrivance, I cause the paddles alternately to enter and leave the
water obliquely, and thereby constantly propel the vessel. The paddles may
be fixed horizontally to the bar D, but in that case they are to be made curved
or flexible without side pieces; in this manner an action on the water, some-
what similar to ordinary rowing, may be obtained. Fig. 11 and 12, g, h, and g, i,
represent two arms of a frame in which the flexible cloth or hide k is fastened,
having the edge k not tight but moderately loose, in the manner of a bag; and
in consequence thereof, whenever by the handle or arm (a) or otherwise the
said frame is either thrust down or drawn up broadwise through the fluid, the
said cloth or hide obtains an oblique position, and by its reaction pushes the
angle (9) onwards through the fluid. Under like circumstances and to produce
a like progressive motion without confining myself to the triangular form, I
do in other constructions make use of and apply one or more longitudinal curved
boards or planes with unequal surfaces formed of elastic and flexible substances
(such as whalebone, canvas, &c.) moving in sockets, and adjusted by stops to
obtain the due inclination. Fig. 13 represents a combination of a number of
such apparatus as was shewn in the last Figures, and in Figure 14 the same
is shewn as affixed to a vessel in which progressive motion may be produced
as aforesaid, or the pitching of the vessel when crossing the waves of the sea
will produce the same effect with very peculiar advantage. Figure 15 repre-
sents an inclined plane plunging paddle, with a vertical handle or lever. The
paddle is made to act between two side pieces, and to describe an angle of 45°
in its motion up and down, and I do apply one or more of these paddles to
such part or parts of the vessel which I wish to move as convenience or
circumstances may point out or require. Figure 16, No. 1, 2, 3, represent
by an upright view and two plans a double paddle or pair of paddles moveable.

page_text: upon a hinge or joint, and having a frame as shewn, or a lever or arm (a), as
in Fig. 17, in a line with the axis of the motion upon the said hinge or joint
or parallel to the said line. Figure 17 shews a combination of a number of
such pairs of paddles, so united and connected with the arm or lever (a) or
other equivalent piece or pieces, as to perform all their respective actions at
once. Figure 18, No. 1 and 2, represents a paddle, of which the acting part
fills or occupies the space included within a suitable frame, and which said
acting part is suspended upon a cross axis (b), at a distance from the centre of
the frame so as to allow the paddle to open and shut, something like the valve
in common use called Belidor's valve. No. 2 shews the manner of opening
and shutting by the resistance of the fluid wherein the said paddle may be
immersed, and of which the effect is, that the direct stroke is made by the
closed paddle, and in the return the paddle is open, and allows that movement
to be made with scarcely any resistance. Figure 19 and 20 shew in different
positions a paddle of the description lastly mentioned, but having an octagon
form or any other form which circumstances may render preferable; a similar
effect may be produced by the adoption of an hinge and stop. Figure 21 is a
double paddle of the description last mentioned. Figure 22 represents a
paddle or oar, having the portions of surface on each side of the handle or
lever (a) to which the same is fixed equal, and consequently not feathering
itself by the mere action of the fluid, and the same is made to feather or
acquire any other position by means of pallets similar to those previously
described in the wheels aforesaid, striking against inclined planes placed at
the extremities of a frame fixed to the sides of the vessel; and I do generally
use two pair of these paddles or oars, in order that one pair may be always
exerting their full action on the fluid.
And lastly, I do declare that the
said means, according to the nature and operation of the same as hereby
explained and described, arc applicable not only to produce or communicate
motion in or unto floating bodies or vessels, but likewise to effect the same
in submarine vessels and in mills and other machinery moved by water or air,
or either of them, and that my apparatus herein described and set forth as
parts of my said Invention may be varied in form and dimensions respectively
in the different constructions as will to competent workmen or mechanics be
easily apprehended and performed without further instructions.
In witness whereof, I, the said James Dawson, have hereunto set my
hand and seal, the Twelfth day of July, in the year of our Lord One
thousand eight hundred and fifteen.

page_text: AND BE IT REMEMBERED, that on the Twelfth day of July, in the year
of our Lord 1815, the aforesaid James Dawson came before our said Lord
the King in His Chancery, and acknowledged the Specification aforesaid, and
all and everything. therein contained and specified, in form above written. And
also the Specification aforesaid was stampt according to the tenor of the
Statute made for that purpose.
Inrolled the Twelfth day of July, in the year Lord One thousand eight
hundred and fifteen.