IMPROVEMENTS IN THE MANUFACTURE OF WROUGHT-IRON PLATES, ADAPTED FOR SHIP-BUILDING AND OTHER PURPOSES FOR WHICH STRENGTH AND LIGHTNESS ARE REQUIRED."
Year: 1855

page_text: LETTERS PATENT to John Herdman, of Belfast, in the County of Antrim,
in Ireland, for the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF
WROUGHT-IRON PLATES, ADAPTED FOR SHIP-BUILDING AND OTHER PURPOSES
FOR WHICH STRENGTH AND LIGHTNESS ARE REQUIRED."
PROVISIONAL SPECIFICATION left by the said John Herdman at the
Office of the Commissioners of Patents, with his Petition, on the 12th
May 1855.
I, JOHN HERDMAN, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF WROUGHT-IRON PLATES, ADAPTED FOR
SHIP-BUILDING AND OTHER PURPOSES FOR WHICH STRENGTH AND LIGHTNESS ARE
REQUIRED," to be as follows:-
I manufacture wrought-iron plates by rolling or otherwise; one surface of
the plate being flat, and the other furnished with a series of ribs, bosses, or
projections, of angular, rectangular, or other suitable form. I heat the ribbed
or bossed surfaces of two such plates to a welding heat, and I place them toge-
ther and weld them by one or more blows of a powerful hammer or hammers,
or by passing them between rolls, or otherwise pressing them together. The
ribs, bosses, or projections on one plate are thus welded to those on the other

page_text: plate. I thus obtain a compound hollow or cellular plate, which possesses
great strength in proportion to its weight, and is well adapted for the construc-
tion of large iron girders, and for ship-building and other purposes.
For
constructing hollow or cellular plates of great thickness, I employ two plates,
similar to those above mentioned, and I place between them one or more plates
with corresponding ribs, bosses, or projections on both surfaces, and I weld the
whole together. For constructing thinner hollow or cellular plates, I some-
times employ one plain plate, and one plate with ribs, bosses, or projections on-
one of its surfaces, and I weld these two together. These hollow or cellular
plates thus consist of two or more surfaces united together by the ribs, bosses,
or projections, the whole being welded together and forming one piece of great
strength, although much lighter than a solid plate of equal thickness. When
greater solidity is required at the edges or other parts of the plates, I insert
iron bars at such parts and weld them in.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Herdman in the Great Seal Patent Office on the
7th November 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HERDMAN, of Belfast, in the County of Antrim, in Ireland, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twelfth day of May, 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 John Herdman, Her special licence that I, the said John Herdman,
my executors, administrators, and assigns, or such others as I, the said
John Herdman, my executors, administrators, and assigns, should at any
time agree with, and no others, from time to time and at all times there-
after 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 "IMPROVE-
MENTS IN THE MANUFACTURE OF WROUGHT IRON PLATES, ADAPTED FOR SHIP-BUILDING
AND OTHER PURPOSES FOR WHICH STRENGTH AND LIGHTNESS ARE REQUIRED," upon
the condition (amongst others) that I, the said John Herdman, my excentors
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

page_text: 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 John Herdman, 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, reference being had to the accompanying Drawing, and
to the figures and letters marked thereon (that is to say) :—
I manufacture wrought-iron plates by rolling or otherwise, one surface of
the plate being flat, and the other furnished with a series of ribs, bosses, or
projections of angular, rectangular, or other suitable form. I heat the ribbed
or bossed surfaces of two such plates to a welding heat, and I place them toge-
ther and weld them by one or more blows of a powerful hammer or hammers,
or by passing them between rollers, or otherwise pressing them together. The
ribs, bosses, or projections on one plate are thus welded to those on the other
plate. I thus obtain a compound hollow or cellular plate, which possesses
great strength in proportion to its weight, and is well adapted for the construc-
tion of large iron girders, and for ship-building and for other purposes. For
constructing hollow or cellular plates of great thickness, I employ two plates,
similar to those above mentioned, and I place between them one or more plates
with corresponding ribs, bosses, or projections on both surfaces, and I weld the
whole together.
For constructing thinner hollow or cellular plates, I some-
times employ one plain plate, and one plate with ribs, bosses, or projections on
one of its surfaces, and I weld these two together. These hollow or cellular
plates thus consist of two or more surfaces united together by the ribs, bosses,
or projections, the whole being welded together and forming one piece of great
strength, although much lighter than a solid plate of equal thickness. When
greater solidity is required at the edges or other parts of the plates, I insert iron
bars at such parts and weld them in.
Figure 1 of the accompanying Drawing is a section, and Figure 2 is a plan,
of a wrought-iron plate with angular ribs; Figure 3 is a plan of a plate with
bosses or projections. The section of this plate is similar to Figure 1. Figure 4
is a section of a plate with rectangular ribs or projections; Figure 5 is a sec-
tion of another plate with rectangular ribs or projections; Figure 6 is a section
of two plates, similar to that shewn in Figure 1; and Figure 7 is a section of
the same plates welded together, to form a compound hollow or cellular plate;
Figure 8 is a section of two plates, similar to that shewn in Figure 1, with
another plate between them, having ribs, or bosses, or projections on both sur-

page_text: faces; Figure 9 is a section of the same plates welded together, and forming a
compound hollow or cellular plate; Figure 10 is a section of a flat plate, and
a plate with ribs, or bosses, or projections; Figure 11 is a section of the same
plates welded together, and forming a hollow or cellular plate; Figure 12 is a
section of a similar plate to that shewn in Figure 7, and having iron bars
inserted and welded at the edges; Figure 13 is a section, shewing one method
of uniting the hollow, or cellular plates. A flat bar of iron is places within
tho two plates and rivetted to them. Figure 14 is a section, showing another
method of uniting the plates. The two surfaces of one of the plates-are bent,
so as to pass between the two surfaces of the other plate; a filling piece is
inserted, if necessary, and the whole is rivetted together. Figure 15 is a sec-
tion, shewing two plates connected in a longitudinal direction by pieces of iron
inserted in the ends of the plates and rivetted to them. Figure 16 is a plan
of one of these plates, with the pieces of iron inserted-in-it. The pieces of iron.
employed to unite the plates may be welded to one of the plates and rivetted
or bolted to the other plate, and in some cases they may be welded to both the
plates, so as to unite them into one plate. Figure 17 is a section of two plates
united together by a piece of iron, which is welded into one of the plates and
rivetted to the other. Figure 18 is a section of two of the hollow plates
rivetted to a T iron, shewing a method of attaching the plates to the ribs of an
iron ship. Figure 19 is a section of a hollow plate with two Tirons rivetted
to it, showing one method of employing the hollow plates in the construction
of girders.
Having now described the nature of the said Invention, and in what mannor
the same is to be performed, I wish it to be understood that what I claim is,
the manufacture of hollow or cellular wrought-iron plates, by welding together
two or more plates with ribs, bosses, or projections between them, in manner
herein-before described.
In witness whereof, I, the said Johu Herdman, have hereunto set my
hand and seal, this Fifth day of November, in the year of our Lord
One thousand eight hundred and fifty-five.
Witness,
THOMAS CALLENDER,
Belfast.
JOHN HERDMAN. (L.s.)