IMPROVE- MENTS IN PROPELLING VESSELS
Year: 1853

page_text: LETTERS PATENT to Thomas Symes Prideaux, of Saint John's
Wood, in the County of Middlesex, for the Invention of "IMPROVE-
MENTS IN PROPELLING VESSELS."
Scaled the 26th July 1853, and dated the 5th May 1853.
PROVISIONAL SPECIFICATION left by the said Thomas Symes
Prideaux at the Office of the Commissioners of Patents, with his
Petition, on the 5th May 1853.
I, THOMAS SYMES PRIDEAUX, of Saint John's Wood, in the County
of Middlesex, do hereby declare that the nature of my Invention of
"IMPROVEMENTS IN PROPELLING VESSELS" to be as follows:-
The design of my Invention is to lessen the quantity of power now
consumed in friction and lateral resistance, and thus diverted from its
proper object of propelling the vessel. To attain this object I make
a portion of my propeller blades flexible, but with this important
difference compared with all previous flexible propellers, viz., that it
shall be so constructed as only to be capable of bending in one
direction; and I still further diminish the friction and lateral resistance

page_text: by receiving the thrust of the propeller shaft on a fluid or soft substance
inserted in a tight cylinder, into which the end of the propeller shaft is
to fit, like the piston of a steam engine fits into its cylinder; whilst,
instead of using gearing or a trunk engine, and suffering the loss from
friction inseparable from either, I propose to work the propeller shaft
direct from the piston by means of two connecting rods jointed to a
ring (attached by appropriate framework to the piston head), which
will traverse the outside of the cylinder, steadied by appropriate guides
or grooves.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas Symes Prideaux in the Great Seal
Patent Office, on the 5th November 1858.
..
TO ALL TO WHOM THESE PRESENTS SHALL COME, 1,
THOMAS SYMES PRIDEAUX, of Saint. John's Wood, in the County of
Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifth day of May, in the year of
our Lord One thousand eight hundred and fifty-three, in the six-
teenth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Thomas Symes Prideaux, Her
special licence that I, the said Thomas Symes Prideaux, my exe-
cutors, administrators, and assigns, or such others as I, the said
Thomas Symes Prideaux, 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 "IMPROVEMENTS IN PROPELLING VES-
SELS," upon the condition (amongst others) that I, the said Thomas
Symes Prideaux, by an instrument in writing under my band and
seal. should particularly describe and ascertain the nature of the said

page_text: Invention, 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 Thomas Symes Prideaux, do
hereby declare the nature of the said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-
tained in and by the following statement thereof (that is to say):
The design of my Invention is to lessen the quantity of power now
consumed in friction and lateral resistance, and thus diverted from its
proper object of propelling the vessel. To attain this object I make
a portion of my propeller blades flexible, but with this important
difference compared with all previous flexible propellers, videlicit, that
it shall be so constructed as only to be capable of bending in one
direction; and I still further diminish the friction and lateral resistance
by receiving the thrust of the propeller shaft on a fluid or soft substance
inserted in an air-tight cylinder, into which the end of the propeller
shaft is to fit, like the piston of a steam engine fits into its cylinder;
whilst, instead of using gearing or a trunk engine, and suffering the
loss from friction inseparable from either. I propose to work the
propeller shaft direct from the piston by means of two connecting rods
jointed to a ring (attached by appropriate framework to the piston
head), which will traverse the outside of the cylinder, steadied by
appropriate guides or grooves.
Having thus stated the nature of my Invention, I will proceed to
describe the manner in which I perform the same.
DESCRIPTION OF THE DRAWING.
Figure 1, represents a plan view of the propeller shaft, with the
propeller attached thereto. Figure 2, is a section of the propeller
through the dotted lines, as shewn in plan. Figure 8, is a vertical
section of an apparatus for receiving the thrust of the propeller shaft.
Figure 4, is an elevation of two cylinders, each of whose pistons are
and the same crank by means of two connecting rods,

page_text: according to my Invention. The same letters are used to indicate the
same parts.
A, A, are the blades of my improved propeller, cach blade consisting
of two parts a', a², connected together by bands of fine steel b, b,
placed on the back sides of the blades, so as to admit of the blades
feathering more or less, according to the resistance encountered. c, c, are
stops placed on the reverse or front sides of the blades so as to prevent
them feathering when the motion of the propeller is reversed to go
astern.
In Figure 3, D, is the propeller shaft, and d, a portion of the same
shaft accurately fitted like a piston into the cylinder e, the cavity f, of
which is kept filled with a fluid or a semi-fluid substance; g, is a pipe
connected with a forcing pump for introducing fluid into the cavity f,
when required; h, is a tube leading to a dynamometer, on which the
thrust exerted by the end of the shaft will be constantly registered; i, is
a tube to be kept filled with oil for lubricating the revolving piston d;
k, is a collar attached to the shaft D, to arrest its thrust, should the
quantity of fluid in f. become insufficient; 1, is an clastic spring, so
arranged as to give motion to the wheel m, which drives the wheel
y which the bell o, is rung before the collar k, can come in contact
with the face of the cylinder e, thus informing the attendant of the
necessity of forcing in a fresh supply of fluid into the cavity f.
In Figure 4, D, is the propeller shaft worked direct from the two
pistons of the cylinders p, p, by means of two connecting rods q, q,
(from each cylinder) jointed to a ring, attached by appropriate frame-s
work to the piston head, and traversing the outside of the cylinder in
appropriate guides or groovess.
Having thus described the nature of my said Invention, and the
manner of performing the same, I would have it understood that I do
not confine myself to the details as herein shewn and described, so long
as the peculiar character of any part of my Invention be retained.
But what I claim is, the constructing propeller blades in such
manner, that they may bend only in one direction.
I also claim the combined means herein described for diminishing

page_text: riction and lateral resistance in respect to the propeller shaft. And I
also claim the giving motion to the propeller shaft herein described.
In witness whereof, I, the said Thomas Symes Prideaux, have
hereunto set my hand and scal, this Fifth day of November,
in the year of our Lord One thousand eight hundred and fifty-
three.
THOMAS SYMES PRIDEAUX. (L.S.)
Witness, WILLIAM TONGUE.