Aк IMPROVED METHOD OF CONSTRUCTING AND PRO- PELLING VESSELS
Year: 1857

page_text: LETTERS PATENT to Alexander John Paterson, of Edinburgh, Esquire,..
for the Invention of "Aк IMPROVED METHOD OF CONSTRUCTING AND PRO-
PELLING VESSELS."
Scaled the 27th October 1857, and dated the 2nd May 1857.
PROVISIONAL SPECIFICATION left by the said Alexander John Paterson
at the Office of the Commissioners of Patents, with his Petition, on the
2nd May 1857.
I, ALEXANDER JOHN PATERSON, of Edinburgh, Esquire, do hereby declare
the nature of the said Invention for "AN. IMPROVED METHOD OF CONSTRUCTING
AND PROPELLING VESSELS," to be as follows:-
My Invention consists in constructing vessels with hollow pointed or conical
drums, of about the same sectional area at their broadest parts as that of the.
vessels themselves, to form the bow and stern, or either bow or stern, and
with screw blades upon the outer surfaces thereof. These hollow screw drums
being made to rotate, will draw and drive or propel the vessel to which they..
are connected, and of which they form part.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filod
by the said Alexander John Paterson in the Great Seal Patent Office
on the 2nd November 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
JOHN PATERSON, of Edinburgh, Esquire, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Second day of May, in the year of our Lord
One thousand eight hundred and fifty-seven, in the twentieth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Alexander John Paterson, Her special licence that I, the said Alexander
John Paterson, my exccutors, administrators, and assigns, or such others
as I, the said Alexander John Paterson, 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 "AN IMPROVED METHOD OF CONSTRUCTING AND PROPELLING VESSELS,"
upon the condition (amongst others) that I, the said Alexander John Paterson,
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.
NOW KNOW YE, that I, the said Alexander John Paterson, 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 tho
following statement thereof, reference being had to the Drawings hereunto
annexed, that is to say:→
My Invention consists in constructing vessels with pointed or conical drums,
of about the same sectional area at their broadest parts as that of the vessels
themselves, to form the bow and stern, or either bow or stern, and with screw
blades upon tlie outer surfaces thereof. These hollow screw drums being made
to rotate, will draw and drive or propel the vessel to which they are connected,
and of which they form part.
If a vessel of the form shown in Figure 1 of the Drawings hereunto
annexed have a thread of a screw of any moderate pitch placed around it and
be made to turn in water in which it has been partially or wholly immersed, it

page_text: will advance either to the right or to the left, according to the direction of its
rotation. The rate of its onward motion will depend upon the pitch of the
thread and the rate of its rotation, and the vessel will thread its way along in
such manner that the resistance upon it will not be greatly augmented as its
speed is increased, and, its slip will therefore be small. Now, if the vessel,
Figure 1, be cut in two at the middle of its length, the base of each pointed
or conical portion be closed, and a hull or vessel of any moderate length, and
with flat ends, equal or nearly equal in area to the said base, be introduced
between the parts, as in Figures 2 and 3 (each of which is a side elevation),
the conditions of the vessel are not much altered in so far as they relate to the
facility with which it may be moved through the water when the pointed or
conical portions are turned. It is upon this consideration mainly that my
Invention is based, and Figure 4 is a side elevation, and Figure 5 a horizontal
view, of a vessel constructed according to it. A is the hull of the vessel; B is
the after propeller; C, the foremost propeller; the latter is supported at the
fore end by a frame D fitted for the purpose. E is a rudder for steering the
vessel. The screws may be driven by any suitable steam or other engine or
engines, and either together or separately, according to the length of the vessel.
The propellers are constructed and weighted in such manner that their aggre-
gate weight at any given time is about equal to that of the water displaced by
them at that time, in order that there may be as little upward or downward
strain as possible upon them. The sides of the vessel may either be straight,
as shewn at a, a, Figure 5, or curved, outward, as shewn at b, b, in the same
Figure. The propellers may be supported by internal instead of, external
stays or supports, as.shewn in Figure 6. When a comparatively great breadth
of beam is required in a vessel, I either employ one largo propeller forward
only partially immersed, as indicated in Figure 7, or two smaller propellers
forward, placed side by side, as indicated in Figures.8 and 9, and threaded and
turned in opposite directions. In the latter case the one vessel would be
equivalent to two vessels of half her size placed side by side, which it might
indeed be by having a channel c, Figure 9, between the two. But the ordinary
form of hull may be preserved by having the part a, Figure 8, cut away, as
indicated by the dotted lines b in the longitudinal side view, Figure 10. In
some cases the stern propeller before described may be replaced if desired by
an ordinary screw propeller, and when two propellers are employed forward
the steru propeller may be altogether dispensed with.
Figures 11 and 12 represent, in side clevation and plan respectively, a vessel.
coustructed for receiving and. fitted with my improved propellers, and well
adapted for navigating shallow rivers. It has two propellers forward, side by

page_text: side, and but half immersed, the water line being at c, d. This vessel would,
however, retain her normal speed if laden to the line a, b, or to any other line
between a, b, and c, d. The propellers may in this case if desired be reduced
in diameter, as shewn in Figure 13, in order that they may be wholly immersed
when the vessel floats at the water line C, d.
And having now described the nature of the said Invention, and in what
manner the same is to be performed, I declaro that I claim, constructing
vessels with pointed or conical drums of the same or nearly the same sectional
area at their broadest parts as that of the vessels themselves at their respective
and corresponding ends, in such manner that these drums shall form the bow
and stern, or cither bow or stern, and shall have formed or fixed upon thom
propelling blades or threads, and be driven by suitable engines, all as herein-.
before described, and represented in the Drawings hereunto annexed.
In witness whereof, I, the said Alexander, John Paterson, have herc-
unto set my hand and seal, this Second day of November, One
thousand eight hundred and fifty-seven.
ALEX. J. PATERSON. (L.B.)