IMPROVEMENTS IN PROPELLING VESSELS
Year: 1841

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
GEORGE TRUSCOTT CAMPBELL, of Lambeth Hill, Upper Thames Street, in the
City of London, Grocer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Nineteenth day of June, in the fourth year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said John
George Truscott Campbell, Her especial licence, full power, sole privilege and
authority, that I, the said John George Truscott Campbell, my exors, admors,
and assigns, or such others as I, the said John George Truscott Campbell, my
exors, admors, or assigns, should at any time agree with, and no others, from
time to time and at all times during the term of years therein expressed, should
and lawfully might make, use, exercise, and vend, within England, Wales, and
the Town of Berwick-upon-Tweed, my Invention of "IMPROVEMENTS IN
PROPELLING VESSELS;" in which said Letters Patent is contained a proviso that I,
the said John George Truscott Campbell, shall cause a particular description of
the nature of the nature of my said Invention, and in what manner the same is
to be performed, to be enrolled in Her said Majesty's High Court of Chancery
within six calendar months next and immediately after the date of the said
in part recited Letters Patent, as in and by the same, reference being thereunto
had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
John George Truscott Campbell, do hereby declare the nature of my Invention,
and the manner in which the same is to be performed, are particularly described
and ascertained in and by the following description thereof, reference being had
to the Drawings hereunto annexed, and to the figures and letters marked thereon
(that is to say)-
"
My Invention of "Improvements in Propelling Vessels' consists in the
application of curious levers or shanks with guides, or levers without guides,
by means of springs and propellers to be worked under water, and whose com-
bined actions are a series of inclined planes moving between two parallels,
thereby producing a very powerful reciprocating undulatory movement with
the least resistance possible, it being only the thickness of the propellers; and
the only place where they can be worked with ease and beneficial effect is in a
hole at the after part of a vessel, immediately before the stern post. Now, to
distinguish this from all others, on account of its peculiar actions, being the
nearest approach to nature, and consequently obtaining the greatest velocity, I
call it the "Whale Tail or. Fluke Propeller." The experimental boat
"Aerolite," which is sixty-nine feet long and nine feet four inches beam, is
fitted with my propellers, made from the following Drawings.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is the elevation, and Figure 2 the plan. (The letters and figures
represent the same parts wherever they occur.) A, the frame, with a fixed
centre Z; B, the starboard lever or shank, with the guides a, b; C, knuckles,
with the principal propeller D, attached, connected to the centre E; F, a rod
connected to the shank at G, and at the principal connecting rod H. This is
for the forward propelling motion; and for the back propelling motion, I is the
larboard lever or shank, with guides c, d; J, knuckles, with the back propeller
K attached, connected to the centre L; M, a rod connected to the centre N,
and at its principal connecting rod 0; P, Q, and R, are brackets or stays, to
keep cach propeller in a horizontal position when reversing the motions.
Figure 3 is the end elevation of the frame A, looking from the bows
towards the stern; Z, the fixed centre; 1, 2, 3 are washers; the open spaces.
represent the situation of the starboard and larboard levers or shanks; 4, section
of the keel; 5, section of the fore and aft timber to receive the upper part of
the frame, the frame being bolted to it, likewise to the keel. The plates 6, 7,
are bolted through the keel and to the frame; the edges of the frame are
bevilled, to present the least resistance to the water. Figure 4 is a plan of
the frame. Figures 5 and 6 represent the elevation and plan of the starboard

page_text: lever or shank; shewing the three centres E, Z, G, which form a right angle,
likewise the guides a, b, which is also a right angle, and is produced by making
each at an angle of 45° from the line Z, E, their distance from E being found
by drawing tangents to a circle whose diameter is equal to the thickness of
the propeller. Figures 7 and 8 represent the elevation and plan of the lar-
board lever or shank, shewing the three centres L, Z, N, likewise the guides
c, d, whose angles and guides are found in the same manner as in the star-
board lever or shank, but inverted. The actions of the propellers are these:-
When the principal connecting rod H, which is moved in guides, and through
a stuffing box in the baulk's head, and has motion given to it from the engine,
and which is communicated to the rod F, also to the lever or shank B, the
point G will move upon the centre Z until, it meets a line drawn through
Z, E, which determines the length of stroke of the principal connecting rod H,
and likewise gives to the propeller the actions of a series of inclined planes,
while passing from the upper to the lower parallel, which is fully and accu-
rately shewn in the diagram, Figure 9, and reversely when passing from the
lower to the upper parallel, as shewn by the dotted lines in Figure 9. The back
motion is worked similar, but reversed. The other method of applying this
principle of propelling is by means of springs, instead of guides, placed securely
upon that part of the lever or shank which is from the fixed centre Z to the
centre E. These springs are intended to clasp the propellers similar to the
knuckles, as at C and J, their flexibility being capable of producing the same
actions as the guides a, b, and c, d. The propellers are formed of boards, and
bound with iron straps, as shewn upon the plan, Figure 2.
Now having fully explained my principle of propelling to the best of my
knowledge, I wish it to be understood, that I do not confine myself from a
right line to any particular angles in the construction of the levers or shanks
and guides, neither to any particular method in constructing the propellers, nor
any particular method of working the propellers, that is, whether horizontally
or vertically, so long as the principle is retained. But what I claim as new is,
first, the levers or shanks having three centres with guides, and the actions of
the propellers, by means of these levers with guides, to any distance between
parallels which may be required.
Secondly, I claim the application of springs, to be used instead of the guides,
as in the manner before described.
In witness whereof, I, the said John George Truscott Campbell, have
hereunto set my hand and seal, this Fourteenth day of December, in
the year of our Lord One thousand eight hundred and forty-one.
JOHN GEORGE TRUSCOTT CAMPBELL (L.B.)

page_text: AND BE IT REMEMBERED, that on the Fourteenth day of December,
in the year of our Lord 1841, the aforesaid John George Truscott Campbel
came before our said Lady the Queen in Her Chancery, and acknowledged
the Specification aforesaid, and all and everything therein contained and speci-
fied, in form above written. And also the Specification aforesaid was stamped,
according to the tenor of the Statute made for that purpose.
Inrolled the Eighteenth day of December, in the year of our Lord One
thousand eight hundred and forty-one.