IMPROVEMENTS IN THE CONSTRUCTION OF BOATS RADMS AND OTHED FLOATING STRUCTURES
Year: 1861

page_text: LETTERS PATENT to Thomas Grahame, of Worthing, in the County of
Sussex, for the Invention of "IMPROVEMENTS IN THE CONSTRUCTION OF
BOATS RADMS AND OTHED FLOATING STRUCTURES"
Sealed the 14th February 1862, and dated the 21st August 1861.
PROVISIONAL SPECIFICATION left by the said Thomas Grahame at the
Office of the Commissioners of Patents, with his Petition, on the 21st
August 1861.
I, THOMAS GRAHAME, of Worthing, in the County of Sussex, do hereby
declare the nature of the Invention for "IMPROVEMENTS IN THE CONSTRUCTION
OP BOATS, RAFTS, AND OTHER FLOATING STRUCTURES," to be as follows:-
This Invention has for its object the construction of boats, rafts, and other
floating structures of greatly increased buoyancy through a reduction in the
amount and weight of materials requisite for their construction, and a saving
in the sacrifice of bearing at stem and stern requisite to give to floating bodies
that angle of entry and exit best fitted to attain a high velocity through water.
The floating portion of the boat, raft, or other floating structure (by the con-
struction and formation of which these improvements are effected), while
protected against the concussions to which floating bodies are subjected, being
at the same time so constructed as to render injury from such concussions
merely partial, without risk to passengers, crew, or cargo, or, indeed, to the

page_text: boat, raft, or floating bridge or structure itself. Boats, rafts, or floating
structures so constructed are especially adapted for the application of steam
power, particularly through the screw. No sacrifice of buoyancy, indeed no
alteration in their formation being required to secure to the screw a full supply
of water, while the steadiness insured by that formation is not more advan-
tageous to the working of the screw or screws than it must be to the comfort
of the passengers and crew. Through that formation the engine and screw or
screws may be brought in direct contact without the intervention of a shaft,
and they may be placed at midships or in any position most suited to obtain
the fullest effect of their force or power while the screw is perfectly secured
against injury from floating bodies or external substances. To effect these
objects the floating superficies of the boat, raft, or bridge, instead of being
constructed in one piece or portion fitted to receive cargo, passengers, and
crew, is divided lengthways into two, three, or more sections or portions, say
troughs, placed alongside but apart from each other.
be placed, and firmly attached, a strongly constructed
extending the entire length of the troughs, and of a breadth sufficient to cover
the same, and the spaces by which they are separated, and extending over the
sides of the outer troughs so far as to protect them from concussions with other
vessels, or in the passage of bridges, tunnels, or on approaching wharfs or
landing places. On this deck the cabins, coverings, and appliances necessary
for passengers, cargo, and crew, are to be erected, also the engine and
necessary machinery when steam power is to be used as a propeller.
On these troughs is to
deck or floor of wood,
To strengthen and secure the floating troughs against the injury the usual
appliances of strong gunwale and bilge plates and cross stringers may be used,
and the ribs being formed like the troughs hollow, of this form U, the troughs
may with ease be divided into such a number of watertight compartments as
to give a perfect security against all risks of sinking or submersion. To these
compartments, and to the tunnels and the machinery to be there placed, access
may be secured through openings in the floor or deck.
As to the distances to be interposed between the troughs, these must be
dependent on the purposes to which the boat, raft, or floating bridge is to be
applied, and on the power to be employed for progression. When from a
limited depth of water or other circumstances the screw or screws used must
be worked wholly or partially in the spaces or tunnels separating the troughs,
the distance must be such as to permit the free action of the screw or screws.
When, from the depth of water or other circumstances, the screw or screws
are so placed as to work at a level under the bottom of the troughs, the distances
between the troughs may be reduced to a space merely sufficient to permit the

page_text: free action of the machinery or gearing working the screw or screws. When
worked in the space or tunnel between the troughs, the screw or screws can be
protected from injury from floating wood and other matters by a guard at the
entrance of the tunnel, and when worked partly or wholly at a level under the
bottom of the troughs the screw or screws may be protected from injury by a
midships keel slightly exceeding the immersion of the lowest portion of the
screw or screws, such as was formerly used in the quick passage boats on the
Scottish canal, to aid the action of the party steering these boats. The deck
being the portion of the boat carrying the passengers, crew, and cargo, and
subject to the action and propelling power of the engine. Every appliance.in
the way of trussing, framework, and the best placement of the wood and metals
used in the construction calculated to strengthen and stiffen it, must be
followed out, as also in its attachment to the troughs and cabins, so as to
make each conduce to the strength and security of the conjoined mass.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Grahame in the Great Seal Patent Office on the
21st February 1862.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
GRAHAME, of Worthing, in the County of Sussex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-first day of August, in the year of our Lord One
thousand eight hundred and sixty-one, in the twenty-fifth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Thomas Grahame, Her special license that I, the said Thomas Grahame, my
executors, administrators, and assigns, or such others as I, the said Thomas
Grahame, 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 "IMPROVEMENTS IN
THE CONSTRUCTION OF BOATS, RAPTS, AND OTHER FLOATING STRUCTURES," upon
the condition (amongst others) that I, the said Thomas Grahame, 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 said Invention, and in what manner the same was to be

page_text: 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 Thomas Grahame, 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):-
This Invention has for its object the construction of boats, rafts, or floating
bodies of an increased buoyancy and steadiness in the water, reducing the
weight of materials necessary for their construction, and the space sacrificed
at stem and stern, in order to obtain the form best suited to pass through the
water, assuring to the passengers conveyed, and the cargo carried on such
floating bodies, when passing along canals or rivers, a perfect and in other
circumstances a greatly increased security against the risks and damage of
submersion, and affording to such passengers and cargo a greatly increased
breadth of accommodation. The Invention is applicable to floating bodies,
whether propelled by animal or mechanical power. To effect these objects,
the floating or under portion of these boats or rafts is to be formed in two,
three, or more longitudinal sections, say, ribbed troughs of iron, or any suitable
material, placed alongside and apart from each other, and fitted to receive and
be firmly attached to and support a deck or floor projecting beyond the outside
lines of these troughs of a strength sufficient to support the cabins or
coverings necessary for the protection of the passengers and cargo, and to
protect these floating trougbs from the effect of concussions at wharfs or in
passing other floating bodies. The troughs to be formed at stem and stern on
the angle of exit and entry best fitted for progression through the water on
which they are to navigate, and of a strength sufficient fully to resist the
pressure to which they must be subjected when submerged by the weight of a
full cargo placed on the deck or carrying platform of which they form the
support, and in farther security these troughs are to be divided from stem to
stern crossways or longitudinally into such a number of watertight divisions as
to make submersion, without an almost total destruction of the troughs them-
selves, almost impossible. Floating bodies so formed are specially adapted for
the application of steam power, particularly the screw. The screw or screws
may be worked, when the depth of water so permits, directly under the floating
body to be propelled, and in almost direct contact with the engine, and in the
best or most suitable position to ensure progression; or they may be worked
in part or wholly in the tunnels separating the bearing troughs.

page_text: The various modes of attaching and connecting the deck or floor and cabins
with the floating troughs, or rather their gunwales, and the mode of applying
steam or other power, being matter of daily practice, it is needless to describe.
The scope and intention of the Invention is the formation of a perfectly
steady, safe boat, affording the largest extent of beam deck or surface accom-
modation possible, and with a form best suited to pass through the water,
these objects being attained by a separation of the carrying or surface accom-
modation and the floating or supporting portions of the boat or raft, in the
manner above described.
In witness whereof, I, the said Thomas Grahame, have hereunto set my
hand and seal, this Nineteenth day of February, in the year of our
THOMAS GRAHAME. (L.S.)