CERTAIN IMPROVEMENTS IN PROPELLING BOATS AND OTHER VESSELS
Year: 1818

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, NICHOLAS
DESFORGES, of Bucklersbury, in the City of London, Merchant, send greeting.
WHEREAS His most Excellent Majesty King George the Third did, by
His Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Thirty-first day of October, in the fifty-eighth year of His
reign, give and grant unto me, the said Nicholas Desforges, my exors, adññiors,
and assigns, His especial licence, full power, sole privilege and authority,
that I, the said Nicholas Desforges, my exors, adiñors, and assigns, should and
lawfully might, during the term of years therein expressed, make, use, exercise,
and vend, within England, Wales, and the Town of Berwick-upon-Tweed,
and in all His Majesty's Colonies and Plantations abroad, the Invention of
"CERTAIN IMPROVEMENTS IN PROPELLING BOATS AND OTHER VESSELS;" in which
said Letters Patent there is contained a proviso that if I, the said Nicholas
Desforges, should not particularly describe and ascertain the nature of the said
Invention, and in what manner the same is to be performed, by an instrument
in writing under my hand and seal, and cause the same to be inrolled in His.
Majesty's High Court of Chancery within six calendar months next and imme-
diately after the date of the said Letters Patent, that then the said Letters
Patent, and all liberties and advantages whatsoever thereby granted, shall utterly
cease, determine, and become void, 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
Nicholas Desforges, do hereby declare that the nature of the said Invention,

page_text: and the manner in which the same is to be performed, are fully described
and ascertained in and by the Drawings hereto annexed, and the following
description thereof (that is to say):-
Beneath the bottom of the boat or other vessel which is to be propelled,
I apply one or more large wings or vanes, which are capable of moving
horizontally, in the direction of the length of the vessel, by means of ropes or
chains which are conducted upwards to the interior of the vessel. To such
ropes the force of men or animals, or of a steam engine can be applied to
give motion to the said vanes, each of which is so constructed that when it is
moved in a direction from the head of the vessel towards the stern thereof,
it will assume a vertical position, and as it moves as an horizontal direction, its
vertical surface will be opposed to the water, and will be so resisted thereby,
that the force which is applied to it will cause the vessel to advance forwards
or be propelled thro' the water. But when the vane has arrived at the end
of its course, it is necessary, in order to repeat the action, the vane shall
return in the direction from the stern towards the head, in that case the vane
will turn upwards on hinges and assume an horizontal position, so that the
edge of the vane will present itself to the water, and will make so little
resistance as not materially to retard the motion of the vessel. Two or
more of such vanes or wings are to be applied to the same vessel to act in
succession, and one will row the vessel forward whilst the other is returning
to repeat its action. The particular manner of carrying this Invention into
execution is represented in the Drawing hereunto annexed, wherein,--.
Fig. 1 is a longitudinal section of a boat or other vessel, with two of the
said rowers or vanes A and B applied beneath the keel thereof. The 1st rower
A is calculated to work backwards and forwards between F and G, whilst the
other works between M and N, but they always move in opposite directions.
The rowers are of a semi-circular figure, as is shewn in Fig. 7, and are made of
thin wood or metal, each rower is attached by a hinge joint to one end of a
bar of metal N, and from the opposite end of the same bar several cords are
extended to the edge of the rower B, as shewn in Fig. 6, in order to prevent
it from moving farther than the perpendicular, but it is at liberty to turn up
upon its hinge, so as to lay flat beneath the bar N. To guide the rower in its
motion, the bar N is united by three pieces of metal h, h, to a strong metal
bar or carriage E, which is shewn separately in Fig. 6. This carriage is
received in a groove formed between two long pieces of wood or metal which I
call conductors, and which are applied beneath the keel of the vessel, as shewn
at C, D, in Fig. 1, and as is also shewn. in Fig. 4, detached from the vessel.
The carriage can move freely backwards and forwards in the groove of the

page_text: conductors, and at each end of the carriage is an eye to attach the ropes by
which it is to be put in motion, these ropes pass over pullies G, F, and M, N,
and are carried upwards into the vessel, through openings made for that
purpose, but the water is prevented from entering into the vessel by trunks or
tubes marked P, Q, and R, which are closely fitted to the bottom of the
vessel around the said openings, and rise up within the vessel above the water
line. The rope belonging to the next advanced rower A passes up thro' the
tubes R and Q, and the rope of the after rower B passes thro' the tubes Q
and P; all the ropes are wrapped round one common barrel I, to which motion
is given either by the force of men, or by steam, so as to turn it round first
in one direction and then to turn it back in an opposite direction, in order to
make the two rowers travel backwards and forwards in the courses assigned to
each of them; but the different ropes are so arranged on the barrell I, that when
one rope moves forwards the other will move backwards, and, as before-
mentioned, when either rower moves from the head of the vessel towards the
stern thereof, that rower will turn down, as shewn at B, that take hold of the
water so as to propel the vessel forwards, but when either rower returns from
the stern towards the head, it will turn up flat beneath the conductor, as
shewn at A, and move edgeways through the water so as to make very little
resistence. The united force of a greater number of men may be made to act
upon the barrel I, in the manner shewn in Fig. 8, where. K are the handles or
cranks which the men turn, and k are small barrels or rollers adapted to the
handles to receive ropes, whereby all the handles K are connected together,
and are also connected with the roller i of the principal barrel I, which
receives the ropes coming from the rollers; or otherwise, when the machinery.
is to be worked by the force of steam, a toothed pinion is fixed on the axis of
the barrel I, and is actuated by a toothed rack, which is fixed to the piston
rod of the steam cylinder, so that the alternate motion of the piston will give
motion to the barrel I, first in one direction and then in the opposite direction.
. Fig. 5 represents another vessel, to which two rowers, like those. before-
mentioned, are applied, but only one perforation is required through the
bottom of the vessel as at P. The conductor for this vessel is made with
two grooves in it, and the carriage of one. rower is applied in each groove;
a pulley F is fixed beneath the advanced part of the keel, and a rope which
passes round this is attached to the carriage of the rower A at one end and
to the carriage of the rower B at the other, so that the rope goes along
one groove and returns along the other, and when one rower is drawn back-
wards the other will be drawn forwards. The motion is communicated
to the carriages E by ropes which pass over the two pullies at G and

page_text: up the tube P; the ropes are then wrapped round the barrel I, which is
put in motion by cranks applied to the axis, as shewn in the transverse section
Fig. 11, and several men may work thereat to turn the barrel backwards and
forwards, or a great number of men may be brought to act in concert by several
cranks combined as before explained.
Figs. 2, 3, and 4 shew the conductor which is applied beneath the keel,
and Fig. 7 is a cross section thereof on a larger scale. C, D, are two
straight beams of wood, which are as long as the keel of the vessel; they
are fixed together & a requisite space left between them by means of iron
bars a, a, which are bolted to both the pieces C, D, and from these bars prongs
rise up at b, b, Fig. 7, to pass on each side of the keel or false keel of the
vessel; but if a boat has no keel then the iron bars a, a, may be made strait
without these prongs, so that the conductor may be applied beneath the flat
bottom. The space between the pieces C, D, is divided into two by a middle
plank e, which is also fixed to the iron bars a, a, so as to form the grooves
wherein the two carriages E can run; planks of wood c, d, and fare fastened be-
neath the two pieces of wood C, D, and e, and the edges of the plank project
beyond the inside edges of the pieces C, D, so as to form narrow ledges, and
each of the carriages E has four small wheels or rollers to run upon these
projecting ledges; and there are also small rollers attached to the bar n, Fig. 6,
which act beneath the said ledges to retain the said bar n from rising, whilst
the wheels in the carriage E keep it from descending, The pieces h, h, Fig. 6,
which descend from the carriage E to support the bar n, pass between the
edges of the two ledges. The conductor is applied to the keel or bottom of
the vessel in such manner that it can readily be detached therefrom when the
vessel goes into shallow water; for this purpose the conductor is fitted to the
bottom of the vessel or to the keel, and each end is fastened up by cords, as
at T, Figs. 1, 4, and 5, so as to fix the same in its place; but when these cords
are released the conductor will be detached from the vessel and may be floated
away therefrom; the said conductor can be readily replaced when required.
For such vessels as are required to navigate shallow water, the rowers may be
made to operate at the sides of the vessels instead of beneath the bottom. In
these cases the conductor may be so formed as to apply to the sides of the
vessel, and one must be applied on each side. Two rowers may be made to
work in cach conductor, or only one, as is found most convenient.
When a boat is built with a square head and stern, it will make an un-
necessary resistance in moving thro' the water. To obviate this I apply
additions to the head and stern of such boat in the manner shewn at R, S, in
Figs. 9 and 10, and the conductor being applied beneath the vessel, and also

page_text: beneath the said additions, will unite them together. The additional pieces
must be made of a pointed figure and fitted to the head and stern of the boat.
At the head of the boat the wheel or bar I is placed to work the rowers as
before described; but it is not necessary to make any perforations in the bottom
of the vessel, because the conducting pulleys M are fixed at the extremity of
the addition R.
My improvements may be applied to propel such vessels as are closed on
all sides, in order to swim beneath the surface of the waters; but in such
cases means must be used to prevent the water from entering into the vessel
at the openings through which the ropes pass. This is shewn in Figure 12,
where P represents the same tube as P in Figure 5, but it is bent at W,
and descends downwards, then makes another bend V and turns upwards,
and is open at the top X. In each of the bends V and W pulleys are fixed
for the ropes to pass over, which communicate motion from the barrel within
the vessel to the rowers, which are without in the same manner as before
described. In the lower bend V of the tube a quantity of mercury is retained
as represented, and this will prevent the entrance of the water into the vessel;
provided the heights of the upright portions W, V, V, are sufficient to contain
such a column of mercury as will counterbalance the pressure which the
surrounding water exerts to enter into the vessel; which pressure will be
greater or less according to the depth which the vessel is beneath the surface
of the water.
Figures 13 and 15 represent two other forms for rowers, which may be
applied in lieu of that one which turns up beneath the conductor, as before
mentioned. The rower, Figure 14, is also of a semi-circular figure, but is
composed of two leaves r and s; these are united by hinges to a vertical bar.
which descends from the forward part of the carriage E, and is braced by an
inclined rod x, so as to be firmly held in a perpendicular direction. The
two leaves of this rower turns upon their hinges like doors, so as to shut flat
against each other, and in that position will make very little resistance to the
water; but when the said leaves open out into one plane, as represented in the
Figure, they oppose their surface to the water.
Figure 15 is a rower, of a circular figure, constructed in a similar manner;
the latter is particularly adapted to be applied to the side of the vessel.
In witness whereof, I, the said Nicholas Desforges, have hereunto set
my hand and seal, this
in the year of our Lord
day of
One thousand eight hundred and eighteen.

page_text: AND BE IT REMEMBERED, that on the Ninth day of November, in the
year of our Lord 1818, the aforesaid Nicholas Desforges (thro' the interpretation
of Joseph Farey, the said interpreter being first duly sworn,) came before our
said Lord the King in His Chancery, and acknowledged the Specification afore-
said, and all and every thing therein contained and specified, in form above
written. And also the Specification aforesaid was stamped according to the
tenor of the Statute made that purpose..