IMPROVEMENTS IN SIDE PROPELLERS FOR OCEAN AND RIVER VESSELS
Year: 1865

page_text: LETTERS PATENT to Luke Thomas, of No. 5, Dawson Place, Bayswater;
in the County of Middlesex, for the Invention of "IMPROVEMENTS IN
SIDE PROPELLERS FOR OCEAN AND RIVER VESSELS."
Sealed the 25th August 1865, and dated the 4th March 1865.
PROVISIONAL SPECIFICATION left by the said Luke Thomas, at the
Office of the Commissioners of Patents, with his Petition, on the 4th
March 1865.
I, LUKE THOMAS, of No. 5, Dawson Place, Bayswater, in the County of
Middlesex, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN SIDE PROPELLERS FOR OCEAN AND RIVER VESSELS," to be as follows:-
My improvements consist in the employment of discs, constructed in such
a manner that they carry upon their outer surface propelling fins or wings..
The discs are carried on shafts worked by the motive machinery of the vessel,.
and are carried one or more on both sides of the vessel at or about the position
in which paddle wheels are placed; or they are placed in other positions at
the sides of the vessel, should they there be found more efficient. The fins or
wings, to the exact form or number of which I do not limit myself, can be.
attached rigidly to the outer surface of the discs
In new vessels in which my improved side propellers are to be used; I prefer
to construct the said vessels with a recess or recesses to receive the said disc

page_text: or discs, so that they, the said disc or discs, may be flush with the sides of the
vessel and yet at the same time rotate freely, the propelling fins only projecting.
When I fit vessels not expressly built for my improved propellers, I fit the
discs as closely as possible to the sides of the vessels, bevelling or reducing the
discs on their outer sides, or sides furthest from the vessel, as much as will be
found consistent with the maintenance of their strength. The fins or wings may
radiate from the centre of the disc, or may be placed at any angle that may
be found most efficient. In some cases it may be found advantageous to attach or
fix at the centre of the disc, where the inner ends of the fins or wings approach
each other, a hollow hemispherical boss. When it is necessary to disconnect
the fins, this can be done from in-board through a port or slide door in the
ship's side, made so that the bolt or bolts that secure the fin can be got at,
and the fin itself hoisted in-board over all from the outside. During the
operation of disconnecting, or when not required to be in motion, the disc can
be secured by lock bolts.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Luke Thomas, in the Great Seal Patent Office on the 2nd
September 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, LUKE
THOMAS, of Number 5, Dawson Place, Bayswater, in the County of Mid-
dlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourth day of March, in the year of our Lord
One thousand eight hundred and sixty-five, in the twenty-seventh year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
I, the said Luke Thomas, Her special licence that I, the said Luke
Thomas, my executors, administrators, and assigns, or such others as I,
the said Luke Thomas, 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 "IM-
PROVEMENTS IN SIDE PROPELLERS FOR OCEAN AND. RIVER VESSELS," upon the
condition (amongst others) that I, the said Luke Thomas, 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
1

page_text: 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 Luke Thomas, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
My improvements consist in the employment of discs constructed in such
manner that they carry upon their outer surface propelling fins or wings
(hereafter in this description the term fin only will be employed). The discs
are to supersede the paddle wheels as at present in use, and the fins the
ordinary paddle board floats. The discs are carried on shafts worked or
rotated by motive machinery within the vessel, and I place one or more of
these discs on both sides of the vessel, at or about the position in which paddle
wheels are usually placed, or at any other position at the sides of the vessel,
should they there be found more efficient. I make the discs of a hollow or
cellular construction, as will be seen by reference to the Drawings, Sheet I.
and II., which are appended to this Specification for the purpose of more parti-
cularly describing the nature of my Invention and the means by which I effect
the same. The discs are countersunk or placed in recesses in the ship's side and
flush with it, so that the propelling fins only project outside beyond the vessel,.
and therefore the discs will not be exposed to the action of the winds or waves or
oppose resistance thereto, as is the case with the common paddle wheel framing..
I do not confine myself to the exact number of fins on each disc; their number,
form, pitch, mode of fixing, and arrangement may differ, and will depend
upon the special application of the disc propellers. Some of these applications
I will now proceed to describe with reference to the herein-before mentioned
Drawings (Sheets I. and II.), observing that in these Drawings. the like
letters are used to denote similar parts in each Figure.. The Figures are:
numbered 1 to 8.
Figures 1 and 2 in the Drawings represent one application of my disc with
fixed fins; Figure 1 is a side elevation of the disc; and Figure 2 is a section at
A, B, of Figure 1. To the disc g are attached the fins a,a,a,a,a,a,a,a. The object.
of the hollow boss b. will be herein-after described. The angle at which the fins
are attached to the disc g is shewn by the two dotted lines C, D, in Figure 2.
The side of the vessel is shewn at e, f, and it will be seen that the disc is quite
inside the vessel, that is, flush with the outside planking or plating. The
hollow disc may be constructed of angle iron covered with thin sheet iron
and made thoroughly water tight.. The fins a, a, a, a, a, a, are so inclined:
.

page_text: as to enter and leave the water in such manner as to offer as little resistance
as possible. From their hollow construction great buoyancy will be given to
the discs g, and they will thus rėleive the ship in proportion; and tend greatly
to ease the vessel in a rolling sea. The object of the hollow boss b is to give
still greater buoyancy and stability, and it is more especially adapted for the
smaller class of vessels, such as coasters and steam tugs, in which it would
not be required to disconnect the fins as herein-after is described.
Figure 3 is a side elevation, and Figure 5 a horizontal section (at E, F, of
Figure 3) of another form of my propellers. The disc g is in all respects the
same as in Figure 1 and 2, but the form of the fins differ. The side view
and plan of the fins a, a, a, a, a, a, are shewn at Figure 3 and Figure 5.
Figure 4 is a section at C, D, (of Figure 3) shewing the manner in which
the fins are attached to the disc g. These fins are also so formed as to give as
little resistance as possible in entering and leaving the water. When navigating
among ice, fius peculiarly or especially adapted for such work can be substituted
for the fins just described and illustrated (Figures 3 and 5), and used during the
time of such service. When it is found necessary to disconnect the fins this
can be done by releasing the bolts that secure the fins to the disc, which can
be got at from within-board through a port or slide door in the ship's side
made for that purpose. The fins being thus unfastened could then be hoisted
in on deck over all. During the operation of disconnecting or connecting, or
when not required to be in motion, the disc can be secured by lock bolts from
the inside. The facility for disconnecting or removing, and also for replacing
the fins in position is very great. When disconnected the ship's side will be
left as free of obstruction as that of any sailing vessel.
'
In Sheet Number II. of the Drawings, Figure 6 is a side elevation; Figure 7
a-section at G, H, (Figure 6) of another form of my improved disc propeller,
in which the fins a, a, a, a, a, a, a, a, are caused to retain a perpendicular
position by means of an eccentric, eccentric levers, and eccentric rods. As
the fins in this arrangement enter and leave the water in a perpendicular
position, or at any required angle, no power is necessarily lost. The disc g is
constructed as herein-before described of angle iron covered with thin sheet
iron. Inside the disc 9.are a number of bushes h, h, h, h,.h, h, h, h, in which
move the spindles k, k, k, k, k, k, k, k, and to the spindles k, k, k, k, k, k, k, k,
are attached externally the fins a, a, a, a, a, a, a, a, and at the back of the
disc the levers i, i, i, i, i, i, i, i. Figure 8 is a separate view of bush h and
eccentric lever i. The fin and spindle may be made in one piece, or separately.
The eccentric levers i, i, i, i, i, i, i, i, are connected to the eccentric ring by
means of the eccentric rods 1, 1, 1, 1, 1, 1, 1, 1.. The eccentric n is attached to

page_text: the side of the ship or on a hollow tube or shaft, through which the main shaft
would in such case work. The eccentric may be placed above, below, or at
an angle to the propelling shaft. With the view of more equalising the strain
on the fins and eccentric gearing they may be connected together by means of a
ring o, o, o. I propose also in some cases to put other bearings without the
vessel for the disc, if it be found advantageous to do so. I may also effect
the retaining of the fins in a perpendicular position by means of a system of
toothed gearing, the driving toothed wheel to be fixed in the centre.
It will be observed that in the Drawing appended to this Specification, that
in the examples of discs with propelling fins the discs are shewn as let into a
recess in the side of the vessel, in such a manner as to be flush with the same
and yet to be free to rotate, the propelling fins only projecting. In some
cases however it may be desired to adapt my propelling disc to vessels already
built, in which it may not be convenient to construct special recesses for the
discs. I then propose to fit the disc as closely as possible. (consistent with
freedom of rotation) to the sides of the vessel, bevelling or reducing the discs
at the edges of their outer sides to such a degree or extent as may be found
consistent with the maintenance of their requisite strength. This modified
arrangement applies only to plans shewn on Sheet Number I. in the
Drawings.
Having now particularly described and ascertained the nature of my
Invention and the means by which the same is effected, I wish it to be
distinctly understood that what I claim is the construction and use of discs in
the manner herein (in this Specification described, or in appended Drawing
illustrated) for the purpose of carrying upon their outer surface propelling
fins or wings for ocean and river vessels. I also claim the combining of the
disc with the boss b.
9
In witness whereof, I, the said Luke Thomas, have hereunto,set my hand
and seal, this Thirty-first day of August, in the year of our Lord
One thousand eight hundred and sixty-five.
Witness,
Thynn, E.
LUKE THOMAS. (L.S.)