IMPROVE- MENTS IN THE CONSTRUCTION OF SHIPS AND OTHER VESSELS
Year: 1852

page_text: LETTERS PATENT to George Randfield Tovell, of Mistley, and
John Mann, junior, Esquire, Justice of the Peace, of Colchester,
both in the County of Essex, for the Invention of "IMPROVEMENTS
Tovell and John Mann, junior, at the Office of the Commissioners
of Patents, with their Petition, on the 18th October 1852.
We, GEORGE RANDFIELD TOVELL, of Mistley, and JOHN MANN, junior,
Esquire, Justice of the Peace, of Colchester, both in the County of
Essex, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN THE CONSTRUCTION OF SHIPS AND OTHER VESSELS" to be as
follows:-
This Invention relates to an improved mode of building ships and
vessels. The ordinary form given to the hull of the vessel, viewed in
transverse section, is that of a curve tapering outwards from the keel
for a short distance, thence suddenly bulging out to the load water line,

page_text: and from thence narrowing inwards to the bulwarks. This form of hull
is modified to suit particular classes of ships, much however being left
to the skill and taste of the builder. Now, I propose to build vessels of
a semi-circular form in their transverse section, this mode having many
advantages over that at present in use. The length and breadth of the
proposed vessel having been decided upon, the horizontal outline may
be drawn, as in Fig. 1, A, B, in the accompanying Drawing.
At different points in the length of the vessel semi-circles are to be
drawn, as at C, D, E; these.show the form of the hull at that part;
and lines dividing the semi-circles into chords a, b, c, show the bevel to
be given to the ribs at that point.
Fig. 2, is the transverse section of a vessel drawn according to this
plan of construction. In building vessels according to this mode, regard
must be had to the service the vessel is intended for. If for fast sailing
or steam, a finer or fuller line, with or less "gripe" or "run," will be
Fequired; if for burthen, the reverse. In some cases it. would. be
desirable to have two keels, which would greatly increase the vessel's
strength, keep her upright when upon the ground, and prevent her
drifting with a "beam wind." Fig. 3, shows this form of vessel. The
circular form given to the "ribs" or timbers of vessels by this mode of
building will greatly increase their strength; and the uniformity of the
water line, whether the ship be upright or heeling over under a press
of canvas, will, it is expected, greatly increase her speed. The form is
also well adapted for a steam ship, as the greater the velocity with
which such a vessel is propelled through the water, the more readily i
will lift itself above the waves, displacing less water, and thus causing
less resistance.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said George Randfield Tovell and John Mann, junior,
in the Great Seal Patent Office, on the 18th April 1853.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we,
GEORGE RANDFIELD TOVELL, of Mistley, and JOHN MANN, junior, Esquire,

page_text: Justice of the Peace, of Colchester, both in the County of Essex, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Hei
Letters Patent, bearing date the Eighteenth day of October, in the year
of our Lord One thousand eight hundred and fifty-two, in the sixteenth
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto us, the said George Randfield Tovell and John Mann, junior,
Her special licence that we, the said George Randfield Tovell and
John Mann, junior, our executors, administrators, and assigns, or such
others as we, the said George Randfield Tovell and John Mann, junior,
our 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 CONSTRUCTION OF SHIPS AND OTHER VESSELS," upon
the condition (amongst others) that we, the said George Randfield
Tovell and John Mann, junior, or one of us, by an instrument in
writing under our 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 we, the said George Randfield Tovell and
John Mann, junior, do hereby declare the nature of our said Invention,
and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement (that is to
say):
Our Invention has for its object the constructing of ships and other
vessels on a new and more simple principle, giving greater strength and
durability, with better sailing qualities. We will first describe our
method of laying down a diagram, from which the curves of the timbers
For ribs of the intended ship may readily be found. The length of the
deck, depth of hold, .length of keel, being decided on (having regard to
the particular service the vessel is intended for), the line A, B, Figure r

page_text: is to be drawn to a given scale; this represents the deck line. Having
added to the depth of the hold, the thickness of the floor timbers, inside
plankings, and keel, at this distance from and parallel to the line A, B,
draw the line C, D, to represent the lower line of the keel, upon which
set off the length of the keel, making allowance for the intended rake
of the stem and stern post. Then draw the lines H, E, forward, and
F, G, aft; these represent the outlines of the stem and stern post. On
these lines mark the points H, I, for the fore and after ends of the load
water line, and at the place of greatest breadth (which may be at any
distance from the stem) mark a point K, shewing the upper part of the
kcel; then with the proper radius draw an arc, cutting the three points
H, K, I. This is to form the top of a solid frame-work connecting the
the stem and stern post by curved dead wood, upon which the frames
forming the hull or body of the ship are to be placed. From the point
H, a line is now to be drawn to a point L; by this line the curves of
the timbers at different points are regulated; the particular angle or
curve to which this line is drawn is entirely arbitrary, and dependant on
the judgment of the designer, of the intended vessel's form, and the
particular service she is required for, as we shall shew after describing
its use.
If it be required to know the form of the timber or frame of
the ship at the point K, draw a perpendicular line from thence to the
line H, L; with the radius M, K, draw the arc N, K, O, carrying it
up to the deck line, which will be the outside form of the timber or
frame of the ship at the point K; and this operation is to be repeated
to determine the form of every rib throughout the vessel's length, in all
cases taking the radii from the line H, L, to the curve formed from the
points of the load water line II, I. It will be observed, that in pro-
portion as the line II, L, rises above or falls below the deck line at any
part of the hull the circles are of greater or less diameter, and con-
sequently the after part is broad as compared with the fore body, where
the line H, L, dips considerably below the deck line. For this part of
the hull where the bow draws in and becomes fine, the semi-circles
formed by radii obtained as before described are too shallow to reach
the sheer line, they must therefore be carried up by perpendicular lines
to the line A, B.

page_text: 19
or
From what has been stated with regard to the line H, L, and the
method of regulating by it the entire form of the intended vessel,
it will be evident that it is only necessary to vary the inclination or
curve of this line to obtain vessels of any form or capacity that may
be required. Thus, if it is desired that the ship should be fuller at the
bows, the line II, L, must be carried upward, as shewn by the dotted
line a, b; if, on the contrary, a finer bow is wanted, the line H, L,
is to be carried lower, as at c, d; the after part of the body or hull
being made finer or fuller, as desired, by varying the line H, L, in the
manner just described, still retaining the form of hull peculiar to this
Invention. Figure 2, represents the half breadth or deck plan of a
vessel, where the breadth and depth of the vessel are alike, the semi-
circles in Figure 1, giving the outline of the one half of the deck of the
intended vessel. Figure 3, is the "sheer plan" longitudinal section
of a vessel drawn to the same scale as Figure 2. P, is the keel upon
which the curved timbers Q, Q, Q, are built, forming the arc H, K, I,
Figure 1. The stem and stern post e, f, being secured to the timbers
Q, Q, Q, the frames R, R, of the hull are then set up; between each
frame a solid chock S, S, is fitted, connecting or supporting each and
all the frames from stem to stern. Over these frames, thus firmly
chocked, the kelson T, is wrought, terminating with a strong wood
knee U, U, fore and aft. The whole of these timbers are firmly secured
together by bolts V, V, passing through them, and secured to the under
side of the keel, uniting also the stem and stern post, and rendering
the frame-work and lower part of the ship one solid mass of timber.
The tendency which a ship of the ordinary construction has for
"hogging" or arching in the centre shews itself from the moment of
launching, and this is increased to a very injurious extent when the
vessel is pitching in a troubled sea; the wave as it rolls under the vessel
lifting it in the centre, while the ends are comparatively without sup-
port; this has the effect of straining and loosening every part of the
ship's framing. Now, the inverted arch form given to the dead wood of
the vessels herein described, and the manner in which the entire frame,
work and keel are bound together, will obviate this evil, or at least tend

page_text: to very considerably mitigate it. A short stem g, is fitted upon the main
stem. to which is secured the fore knee U; it also receives the fore end
of the top planking, and gives additional strength to the fore body be-
yond the stem g, which is further secured to the main stem by a knee h;
or the fore part timber may be carried to form the head, or give any orna-
mental finish that may be desired. Additional strength and security are
also given to the stem of the ship by filling in the hull inside the stem post
with a water-tight bulk-head i, of solid timber; beyond the stern post
the timbers and deck may be carried out to any extent desired to form
an overhanging stern, as partly shewn at g. Now, should this portion
of the ship be carried away by collision or the force of the waves, the
strong partition i, will preserve the vessel from further damage by the
ingress of water. To add to the strength of the upper part of the hull,
on the inner side of the frames, and level with the deck, we attach strong
double waterways p, p, of oak; these are carried round the vessel, and
firmly bolted to the ribs and beams, and to these the bulwarks are
secured, so that on the ship being struck the additional resistance of the
double waterways are offered to the opposing force; and the bulwark
staunchions being within the outer frames, and through the oak water-
ways p, p, are not so liable to be carried away, as the bulwark is kept
clear of the sea when the ship is under canvass. We give to the keel
the form of a double arc, as shewn at Figure 7, tapering it off at either
end where the reduced weight is advantageous. Figure 4, is a transverse
section at midships of Figures 1, 3. Figure 5, is a section of a vessel
having a double keel; this arrangement is useful for merchant vessels
or steam ships, the double keel keeping the vessel upright when aground,
and lessening the draught of water by the depth of the centre keel.
The section Figure 6, shews a section of thick garboard strakes, so as to
retain the outward circular form, and give the requisite strength, with
nearly straight timber.
Having now described the nature of our Invention, and how the
same is to be performed, we would have it understood that we do not
confine ourselves to the precise details herein-before described and
shewn, as some of these may be varied without departing from the

page_text: principle of our Invention. But we claim the improved mode of
constructing ships and other vessels, substantially as herein-before
described and shewn.
In witness whereof, we, the said George Randfield Tovell and
John Mann, junior, have hereunto set our hands and seals,
this Fourteenth day of April, in the year of our Lord One
thousand eight hundred and fifty-three.
(L.S.) GEORGE RANDFIELD TOVELL.
(L.S.) JOHN MANN, JUNIOR.