IMPROVEMENTS IN THE PROPULSION OF VESSELS, AND IN APPARATUS FOR THE SAME
Year: 1872

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane,
in the County of Middlesex, Patent Agent, for the Invention of
"IMPROVEMENTS IN THE PROPULSION OF VESSELS, AND IN APPARATUS FOR THE
SAME." A communication from abroad by Alexandre Hédiard, of
13, Boulevart St. Martin, Paris.
Sealed the 26th July 1872, and dated the 10th February 1872.
PROVISIONAL SPECIFICATION left by the said Alexander Melville
Clark at the Office of the Commissioners of Patents, with his
Petition, on the 10th February 1872.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN THE PROPULSION OF VESSELS, AND
IN APPARATUS FOR THE SAME," to be as follows:-

page_text: arranged below the water line, and its use is attended with very con-
siderable economy, inasmuch as engines, paddles, and screws, and their
attendant mechanism are dispensed with, while with this improved
system of propulsion one stoker only is required to attend to the
boilers.
This Invention is illustrated in the accompanying Drawing, Figure 1
of which shows a central longitudinal section of the stern portion of a
vessel fitted with the improved propelling apparatus, Figure 2 showing
a longitudinal section of the latter detached. The reference letters
apply to both Figures.
The steam supplied from boiler a is projected through a conical
nozzle b into a submerged open cylindrical chamber slightly enlarged at
the mouth, and through which chamber the water is drawn by the jet of
steam, as indicated by the arrows in Figure 2. The size of the orifice in
the steam nozzle is dependont on the size of the vessel, as is also the
sectional area of the chamber c. The column of water thus impelled
through the chamber c by the steam jet acquires a considerable velocity,
and being projected continuously produces a power by reason of its
volume and speed which acts continuously against the surrounding
water, the apparatus being disposed at such an angle as to produce the
reaction by which the vessel is propelled. It follows that as the point
of resistance is being continually renewed by the motion of the water
so the vessel will be continually propelled at a speed dependent only on
the amount of steam employed.
The apparatus may be placed in a line with the keel, or one or more
on either side of the same.
It will be understood that each apparatus is divided into two parts for
propelling in a forward and backward direction.
When the apparatus is of large dimensions several jets of steam may
be employed in order to obtain a larger surface of steam to act more
effectually on the column of water and obtain the necessary speed.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexander Melville Clark in the Great Seal Patent
Office on the 8th August 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Tenth day of February, in the
year of our Lord One thousand eight hundred and seventy-two, in the
thirty-fifth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Alexander Melville Clark,
Her special licence that I, the said Alexander Melville Clark, my
executors, administrators, and assigns, or such others as I, the said
Alexander Melville Clark, 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 THE PROPULSION OF VESSELS,
AND IN APPARATUS FOR THE SAME," a communication to me from abroad
by Alexandre Hédiard, of 13, Boulevart St. Martin, Paris, upon the
condition (amongst others) that I, the said Alexander Melville Clark,
my executors or administrators, by an instrument in writing under
my, or their, or one of their hands and seals, should particularly
describe and ascertain the nature of the said 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.
66
NOW KNOW YE, that I, the said Alexander Melville Clark, do
hereby declare the nature of the said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement, reference being had to the accom-
panying Sheet of Drawings, and to the letters and figures marked
thereon (that is to say)
:-
This Invention relates to an improved mode of and apparatus for pro-

page_text: pelling vessels. The propeller which is of very simple construction is
disposed below the water line, and its use is attended with very con-
siderable economy, inasmuch as engines, paddles, and screws, and their
attendant mechanism are dispensed with, while with this improved
system of propulsion one stoker only will generally suffice to attend to
the boilers.
This Invention is illustrated in the accompanying Drawing, Figure 1
of which shows a central longitudinal section of the after portion of a
vessel fitted with the improved propelling apparatus, Figure 2 showing
a longitudinal section of the latter detached. The reference letters apply
to both Figures.
The steam supplied from boiler a is projected through a conical
nozzle 6 into a submerged open cylindrical chamber slightly enlarged at
the mouth, and through which chamber the water is drawn by the jet of
steam, as indicated by the arrows in Figure 2. The size of the orifice in
the steam nozzle is dependent on the tonnage of the vessel, as is also
the sectional area of the chamber c. The column of water is impelled
through the chamber c by the steam jet at a considerable velocity, and
by reason of its volume and speed acts continuously with such force
against the surrounding water (the apparatus being disposed at an angle
as shown) as to produce the reaction by which the vessel is propelled.
It follows that as the point of resistance is being continually renewed
by the motion of the vessel through the water so the vessel will be con-
tinuously propelled at a speed dependent only on the amount of steam
employed.
The apparatus may be placed in a line with the keel, or one or more
apparatus may be placed on either side of the same.
It will be understood that each apparatus is divided into two parts for
propelling in a forward and backward direction.
When the apparatus is of large dimensions several jets of steam may
be employed in order to impel the column of water at the highest
possible speed.
Having described the nature of the Invention, and in what manner
the same is to be performed, I declare that what I claim as the Inven-
tion to be protected by the herein-before in part recited Letters Patent
is, the improved method of and apparatus for propelling vessels herein.

page_text: described and shown in the Drawings, in which a jet (or jets) of steam
is projected through an open submerged cylindrical chamber disposed at
an angle, substantially as set forth, for producing a current whose
reaction on the surrounding water propels the vessel.
In witness whereof, I, the said Alexander Melville Clark, have
hereunto set my hand and seal, this Eighth day of August, in
the year of our Lord One thousand eight hundred and seventy-
two.