IM- PROVEMENTS IN PREPARING AND FIXING IRON AND OTHER METAL PLATES TO SHIPS AND OTHER STRUCTURES
Year: 1860

page_text: LETTERS PATENT to Thomas William Plum, of Blaenavon Iron Works,
in the County of Monmouth, Ironmaster, for the Invention of "IM-
PROVEMENTS IN PREPARING AND FIXING IRON AND OTHER METAL PLATES TO
SHIPS AND OTHER STRUCTURES."
Sealed the 17th August 1860, in pursuance of an Order of the Lord Chancellor,
PROVISIONAL SPECIFICATION left by the said Thomas William Plum
at the Office of the Commissioners of Patents, with his Petition, on the
26th January 1860.
I, THOMAS WILLIAM PLUM, of Blaenavon Iron Works, in the County of
Monmouth, Ironmaster, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN PREPARING AND FIXING IRON AND OTHER METAL PLATES
TO SHIPS AND OTHER STRUCTURES," to be as follows:-
This Invention comprises a mode of making and fixing shield or other
metal plates to ships or batteries, so that the fixing or holding, of. the plates is
accomplished by means of ribs without perforating the plates, which are.
themselves made to shield the fixings, and the joints tightened by the impinge-
ment of external force upon them. For these purposes it is intended to use
wrought-iron or other metal "fixing ribs," so made with "flange and T-head."
or "flange and dovetailed" ribs, suitably shaped in one or other of various
forms of dovetail for securely holding the plates. The said ribs are bolted
through their flanges to the ship or battery. by suitable ordinary bolts. The

page_text: edges of the plates are formed to suit the shape of the ribs, and are inserted
by sliding them between the dovetailed parts of an upper and lower rib; but
in preparing and fixing the said ribs the bolt holes in the lower flange of every
rib, except the lowest of all, are to be slotted, or made slightly oval in shape
in the transverse direction of the rib, and the bolts in the upper side or flange
of the rib are not to be secured until the plate has been inserted under it, the
insertion of the plate being materially facilitated by the rise of the rib,
permitted by the slotted bolt holes before described; when each plate has
been thus brought to its proper place the rib over it is forced down tightly
upon the plate by any suitable known means, as cramps, or the application of
hydraulic power; the upper side of the rib is then bolted through its flange,
and thus a series of ribs and plates are fixed one above another to any required
extent. The bottom and top ribs for the lower and upper tier affixed to any
ship or battery are made of greater depth or different form, for the purpose of
their outer edge, against which there would not be any plate, being shaped off
to form a secure and suitable finish in these and other terminating parts.
SPECIFICATION filed in pursuance of the conditions of the Letters Patent,
and of an Order of the Lord Chancellor, by the said Thomas William
Plum in the Great Seal Patent Office on the 25th August 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
WILLIAM PLUM, of Blaenavon Iron Works, in the County of Monmouth, Iron-
master, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-sixth day of January, in the year of our
Lord One thousand eight hundred and sixty, in the twenty-third year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Thomas William Plum, Her special licence, that I, the said Thomas
William Plum, my executors, administrators, and assigns, or such others as
I, the said Thomas William Plum, 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 PREPARING AND FIXING IRON AND OTHER METAL PLATES
TO SHIPS AND OTHER STRUCTURES," upon the condition (amongst others) that I,
the said Thomas William Plum, my exccutors or administrators, by an

page_text: 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 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 William Plum, do hereby
declare the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement thereof, reference being had to the Drawings hereunto
annexed, that is to say :-
For shielding ships and batteries on land or floating with thick metal
armour plates, I use metal ribs with a flange or flanges, through which
they are to be bolted to the ship, battery, or other structure, and a
dovetailed or T-head rib for holding the plates. The flange and dove-
tailed ribs a, a, b, may be of the forms shewn in the Drawing hereunto
annexed, or of any similar form, so that there be a flange or flanges for bolting
through, and a transverse head having 'more or less of dovetail shape, in order
that when the plates which are to be prepared to fit the ribs are inserted
between two of such ribs,; they will be securely held in their intended position,
that the plates when fixed shall cover the bolt holes, and that the joints or
points of junction between the plates and ribs shall have a tendency to tighten
when struck on or near the joints. In preparing the ribs, except the first, to
be fixed to any structure, the bolt holes in one side of the flanges of the ribs
are to be made longer, i.e., oval in form in the transverse direction of the rib,
so as to admit of the second and successively fixed ribs being in the first place
bolted through the elongated bolt holes far enough from the rib previously
fixed to allow the plates to be inserted between them without difficulty, and
the rib to be then drawn by cramps or other known means tightly to the
plate; the row of bolts on the other side of the rib are then put in and made
fast. The upper and lower, and vertical end ribs are made with one side only
prepared to receive or hold plates, the other being rounded, moulded, or
bevilled off in any suitable shape, as at b. The space between the back of the
plates and the face of the ship or other structure shewn at c, c, c, may be more
or less according to the dimensious determined for the ribs and plates, and
may be filled with any material that may be found most suitable.
I do not confine myself to any particular form or dimension of either rib or
plate; but what I claim as my Invention is,―
First, the mode of fixing armour plates to ships or batteries by means of
dovetailed or T-head ribs, with flanges for bolting, as herein-before described.

page_text: Secondly, the mode of inserting. and thus securely holding such plates
without the necessity for perforating them, whereby at the same time butt
joints are avoided, and the plates to a great extent cover and protect the fixing
bolts, as herein-before described.
In witness whereof, I, the said Thomas William Plum, have hereunto
set my hand and seal, this Twenty-second day of August, One thousand
eight hundred and sixty.
THOS. W. PLUM. (L.S.)