IMPROVEMENTS IN THE CONSTRUCTION OF SHIPS' MASTS AND SPARS
Year: 1864

page_text: LETTERS PATENT to John Bassett Elwell, of Priestfield, near Bilston, in
the County of Stafford, Boiler Maker, for the Invention of "IMPROVEMENTS
IN THE CONSTRUCTION OF SHIPS' MASTS AND SPARS."
Sealed the 31st March 1864, and dated the 6th January 1864.
PROVISIONAL SPECIFICATION left by the said John Bassett Elwell.
at the Office of the Commissioners of Patents, with his Petition, on
the 6th January 1864.
I, JOHN BASSETT ELWELL, of Priestfield, near Bilston, in the County of
Stafford, Boiler Maker, do hereby declare the nature of the Invention for
"IMPROVEMENTS IN THE CONSTRUCTION OF SHIPS' MASTS AND SPARS," to be as
follows:-
This Invention has for its object improvements in the construction of ships'
masts and spars. In constructing ships' masts and spars according to this
Invention I form them of tubes composed of sheets or plates of metal con-
nected together in such manner that the joints uniting together the side edges
of the plates shall run spirally from end to end of the mast or spar, the plate
being for this purpose bent to the requisite spiral form, by which means the
masts or spars will be of much greater strength than when the plates are con-

page_text: nected together with the joints that unite them running parallel with, and also
at right angles, to the length of the mast or spar. The joints that run spirally
from end to end of the mast or spar I by preference form by making the edges
of the plates to overlap each other, and connecting together the overlaping
edges by rivets, and were two plates come together end to end, I, by preference
connect them together by butt joints, the neigboring ends of two plates being
each rivetted to a short plate that overlaps both of them, this short plate being
interior of the mast or spar. The sheets of metal employed are equal in width
to one-half, third, or other part of the circumference of the mast or spar, so that
it will require two, three, or more plates bent to the requisite curve and con-
nected together side by side to form the circumference of the mast or spar.
The spiral to which the plates are bent I prefer to be such that the spiral
lines formed by the joints, by which the side edges of the plates are connected
together, shall pass entirely around the mast or spar in a length equal to about
9 or 12 times its diameter, but this may be greatly varied. Where the mast
or spar is required to be tapered, the plates are cut to the requisite taper form,
and are bent to the requisite curve, which I by preference do by means of
rollers, stengthening ribs of T, or angle iron may if desired be employed
interior of the mast or spar.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Bassett Elwell in the Great Seal Patent Office on the
6th July 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
BASSETT ELWELL, of Priestfield, near Bilston, in the County of Stafford,
Boiler Maker, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixth day of January, in the year of our Lord
One thousand eight hundred and sixty-four, in the twenty-seventh year
of Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said John Bassett Elwell, Her special licence that I, the said
John Bassett Elwell, my executors, administrators, and assigns, or such
others as I, the said John Bassett Elwell, 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

page_text: Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF SHIPS' MASTS AND
SPARS," upon the condition (amongst others) that I, the said John Bassett
Elwell, 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 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 Bassett Elwell, do hereby
declare the nature of the 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, that is to say :-
This Invention has for its object improvements in the construction of ships'
masts and spars. In constructing ships' masts and spars according to this
Invention I form them of tubes composed of sheets or plates of metal con-
nected together in such manner that the joints uniting together the side edges
of the plates shall run spirally from end to end of the mast or spar, the plates
being for this purpose bent to the requisite spiral form, by which means the
masts or spars will be of much greater strength than when the plates are con-
nected together with the joints that unite them running parallel with and also at
right angles to the length of the mast or spar. The joints that run spirally
from end to end of the mast or spar I by preference form by making the edges
of the plates to overlap each other, and connecting together the overlapping
edges by rivets, and where two plates come together end to end, I, by preference,
connect them together by butt joints, the neighboring ends of two plates being
each rivetted to a short plate that overlaps both of them, this short plate being
interior of the mast or spar. The sheets of metal employed are made of such
a width that it will require two, three, or more plates bent to the requisite curve
and connected together side by side to form the circumference of the mast or
spar. The spiral to which the plates are bent, I prefer to be such that the
spiral lines formed by the joints, by which the side edges of the plates are
connected together, shall pass entirely around the mast or spar in a length
equal to about 9 or 12 times its diameter, but this may be greatly varied.
Where the mast or spar is required to be tapered, the plates are cut to the
requisite taper form and are bent to the requisite curve which I by preference
do by means of rollers, strengthening ribs of T or angle iron may if desired be
employed interior of the mast or spar.
The annexed Drawing shows a side view of a portion of a mast constructed
in the manner above described, and other spars are constructed in a similar

page_text: :manner.
The cheeks and other fittings of the mast may be formed and
applied in the manner usual in constructing metal masts.
In witness whereof, I, the said John Bassett Elwell have hereunto set
my hand and seal, this Second day of July, in the year of our Lord
One thousand eight hundred and sixty-four.
JOHN BASSET ELWELL. (L.S.)