IMPROVEMENTS IN CONSTRUCTING LIFE BOATS
Year: 1855

page_text: LETTERS PATENT to Nathan Thompson, junior, of New York, for the
Invention of "IMPROVEMENTS IN CONSTRUCTING LIFE BOATS."
Sealed the 3rd August 1855, and dated the 23rd February 1855.
PROVISIONAL SPECIFICATION left by the said Nathan Thompson at
the Office of the Commissioners of Patents, with his Petition, on the
23rd February 1855.
I, NATHAN THOMPSON, junior, of New York, do hereby declare the nature
of the Invention for "IMPROVEMENTS IN CONSTRUCTING LIFE BOATS" to be as
follows:-
The object of this Invention is to construct life boats in such manner that
they may be more readily folded and packed and carried than those heretoforo
made. For this purpose the two sides of a boat are each made of two pieces,
hinged or connected together, the joint where they are hinged or connected
being made water-tight by waterproof fabric or material; the two sides of the
boat are connected together so as to form the two ends of the boat, the parts
connected being rendered water-tight by waterproof fabric or material. The
sides are not made so deep in the centre of the boat as at the two ends.
Between the two sides is a longitudinal partition, to which the two parts con-
stituting the floor or bottom are hinged, so that when they are brought into a
horizontal position, or nearly so, they keep the two sides of the boat opened

page_text: out.
The under part of the boat is rendered water-tight by waterproof fabric
or material. The seats are in parts hinged to the sides and to the central
partition, so that when the boat is opened out and retained so by the floor the
seats will be expanded.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Nathan Thompson in the Great Seal Patent Office on the
23rd August 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, NATHAN
THOMPSON, jr, of New York, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-third day of February, in the year of our
Lord One thousand eight hundred and fifty-five, in the eighteenth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Nathan Thompson, Her special licence that I, the said
Nathan Thompson, my executors, administrators, and assigns, or such
others as I, the said Nathan Thompson, 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 King-
dom of Great Britain and Ireland, the Channel Islands, and Isle of Man, an
Invention for "IMPROVEMENTS IN CONSTRUCTING LIFE BOATS," upon the condition
(amongst others) that I, the said Nathan Thompson, by an instrument
in writing under my hand and seal, 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 Nathan Thompson, do hereby declare
the nature of the 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 thereof (that is to say) :-
In the Drawings, Figure 1 is the general plan of a life boat constructed
according to my Invention; Figure 2 is the central transverse section;
Figure 3 is an end view; Figure 4 is a longitudinal section; Figure 5 is a
transverse section of the boat when closed; Figure 6 is a transverse section of
the boat when half opened; Figure 7 is an exterior view of the joints between

page_text: the different parts of the side of the boat; Figure 8 is an end view of the
exterior of the metal joint in each end of the boat, and corresponding with (A)
in Figure 4. In Figure 1 the plan of the same joint is also given at (A).
This joint is connected with a longitudinal brace or kelson (B), which extends
the whole length of the boat. When open, a side view of it is seen in Figure 4,
and the upper edge in Figure 1.
Inasmuch as the boat is longer when closed than when open, it is necessary
to connect the end joint with slots or longitudinal openings, the joints having
a pin or slider to run in them, so as to have the effect of elongating the centre
brace or kelson, and shortening the same, according to the exigencies of the
occasion. Figure 1, general plan, shows the cross braces C swung open, these
cross braces opening like common gates from the longitudinal brace or kelson
B, and serve the triple purpose of a brace to hold open the sides of the boat,
and to hold the bottom down and support seats D for oarsmen.
On the top end of the cross brace C is an iron fixture E, with a slot or
opening to take a pin or bolt attached in a groove F in the side of the boat, so
that in swinging the cross braces open the sides are fastened instantly. The
bottom is fastened on the same principle to take the transverse strain on steady
pins on a flange all along the interior of the bottom edge of the sides of the
boat, and as the bottom falls on the flange it catches the steady pins and holds
the sides firmly. In Figure 2 is a central transverse section, of which the
following additional description is given; herein may be seen the sides G,
bottom H, keel and longitudinal brace or kelson painted yellow, and what is
very important to be noticed, waterproof canvass, vulcanized india-rubber, or
sole Icather joints are attached, as shown, to prevent leakage; a part of the
bottom may be seen raised up, as at I, to give greater security and protection
to the canvas. This waterproof canvas, vulcanized india-rubber, or leather is
fastened to the upper side of the exterior edge of the bottom of the boat, and
extending up the load line, or it may extend all or partly over the bottom of
the boat. Thus also the joints along the longitudinal brace or kelson are
covered with waterproof canvas, and in the same way the joints in the sides
of the boat are rendered waterproof, the cloth being protected from abrasion
and damage by being all inside the bottom of the boat. By a reference to
Figure 1 (general plan) it will be seen that the wood work forming the sides
of the boat extends beyond the end of the hinges in both ends of the boat;
and by reference again to Figure 2 it will appear that this wood work is
hollow, with air chambers, or may be filled with cork to secure buoyancy.
Second, the adaptation of this Invention as a gun and military bridge boat.
In Figure 9, a transverse section, the hinges of the solid flooring K are

page_text: attached to the top of the longitudinal brace or kelson B, and fall on the cross
braces C and sides G of the boat to form a deck, the same as the bottom H
falls from the lower edge of the longitudinal brace or kelson, as before
described. Figure 10 is a disposition of the boats joined to form a bridge for
the passage of troops and materials of war. It will be seen that in those
military boats there are altogether only four joints in the sides of the boat,
while in that first described there are four more, to give a curve to the
outline of the sides, also greater capacity, but the military boats' flat sides
are better, as they lock more firmly to each other, as seen in the Diagram.
In order to construct my boat I procure two sides of rigid material in
sections connected together by proper hinges, and attach these sides each to
each at the ends by hinges between these two ends. I locate a longitudinal
brace or kelson, secured to the end hinges in such manner that the sides may
slide lengthwise of the said brace or kelson; and to this brace or kelson, as
before remarked, I hinge a solid floor, one on each side of said brace or kelson,
also cross braces to hold the bottom down in its place when swung open, the
said solid floorings or bottom of the boat rising up along the longitudinal brace
or kelson when the boat is closed, and falling down perpendicular to the
kelson, or nearly so, when the boat is open out.
The position of the slider is not material; it may be at either end, or they
may be in the hinges themselves in the sides of the boat, or one slider only
may be used, the other end fixed not to slide. The boat when expanded has
some dead rise in the flow, so that it allows the projection of the sides below
the bottom of the boat; I prefer its remaining, to give greater strength to the
centre of the boat, also greater stiffness to the boat while in the water, serving
also as means to secure oneself to the bottom of the boat in case the boat is
capsized in the trough of the sea; but I can also cut off said projection if
circumstances should require it. Now, I have described this boat as having
air chambers in the sides, but it is clear, without altering the principle of my
Invention, that such sides may be single, of springy wood without hinges in said
sides, and that I may make the longitudinal brace or kelson brace or kelson
hollow, with air chambers in connection with the sides, or without the sides
being fitted with air chambers, and that the same sides may be a framework
partitioned off for air chambers, or filled with cork, or the said sides may be
made of metal with air chambers; in fact, the whole exterior of the boat may
be metal as well as of wood. I intend always to adopt some such plan, so that
my boats may be life boats. The bottom, moreover, may be hinged to the
sides instead of the longitudinal brace or kelson, and will serve as nearly as
good a purpose. When the boat is expanded there may be metallic braces

page_text: with eyes and hooks, if deemed necessary, and would materially stiffen the
boat when afloat.
These boats in addition may have all appurtenances, painters, rudders,
fenders, rowlocks, et cetera, such as are attached to ordinary boats.
Having thus described my life boat and military bridge boat, I claim therein
as of my own Invention, and desire to secure by Patent, a boat for civil and
military purposes made and described as above. As to details, I claim more
especially,-
First, the longitudinal brace or kelson, with slots or longitudinal openings
and sliders attached to each end of said brace or kelson.
Second, I claim the hinging of the bottom on to a longitudinal brace or
kelson, as within described.
Third, I claim the swinging brace with seats attached to lock in the sides,
as within specified.
Fourth, I claim the attachment of waterproof canvass, or leather, or other
equivalent material, to the joints of solid material, forming the sides and bottom
of a boat, as within specified.
In witness whereof, I, the said Nathan Thompson, have hereunto set my
hand and seal, this Twelfth day of June, in the year of our Lord One
thousand eight hundred and fifty-five.
Witness,
W. CARPMAEL, junr.
NATHAN THOMPSON, JR. (L.S.)