IMPROVEMENTS IN THE CONSTRUCTION OF WROUGHT- IRON MASTS, BOWSPRITS, YARDS, BOOMS, GAFFS, AND SPARS, AND IN RIGGING SHIPS
Year: 1856

page_text: LETTERS PATENT to Edward Finch, of Bridge Works, Chepstow, Engineer,
for the Invention of "IMPROVEMENTS IN THE CONSTRUCTION OF WROUGHT-
IRON MASTS, BOWSPRITS, YARDS, BOOMS, GAFFS, AND SPARS, AND IN RIGGING
SHIPS."
Sealed the 18th March 1857, and dated the 19th September 1856.
PROVISIONAL SPECIFICATION left by the said Edward Finch at the
Office of the Commissioners of Patents, with his Petition, on the 19th
September 1856.
I, EDWARD FINCH, of Bridge Works, Chepstow, Engineer, do hereby
declare the nature of the Invention for "IMPROVEMENTS IN THE CONSTRUCTION
OF WROUGHT-IRON MASTS, BOWSPRITS, YARDS, BOOKS, GAFFS, AND SPARS, AND IN
RIGGING SHIPS," to be as follows:-
In the construction of wrought-iron masts, bowsprits, yards, booms, gaffs,
and spars, cylindrical in shape, for large ships, it is necessary that the outer
shell should be of strong boiler-plate iron, and that at the joints the iron
should be in perfect contact. In large masts, &c., of this shape great expense
is incurred and difficulty experienced in bending the plates to the required
curve, and bringing the edges when put together in close contact with each
other, and this difficulty increases as the size of the mast, and consequently
the strength of the plates is increased.
In the construction of the above of small size great difficulty is experienced
in rivetting the plates to the internal T-angle irons or butt plates when the

page_text: diameter will not admit of a boy getting inside to insert and bold up the rivets
while they are being rivetted from the outside.
Now, my improvements consist, first, in making wrought-iron masts,
bowsprits, yards, booms, gaffs, and spars multilatiral in shape instead of
cylindrical, thereby dispensing with the bending of the plates and much 5
facilitating the construction, and this I carry out by procuring a number of
plates equal to the number of sides determined upon, and a number of angle
irons equal to the number of angles formed by the junction of the sides.
To the angle irons I rivet the side plates, and the more effectually to bring the
plates in contact, I plane both the vertical and horizontal edges of the plates to 1
form the joints; and to give uniformity of strength and elasticity, I cause the
plates to break joint with each other, and I weld the angle irons up in one
piece for the entire length required.
My second improvement consists in doing away with the necessity, in masts,
bowsprits, yards, booms, gaffs, and spars of small size, of putting in the rivets
from the inside, and holding them up while being rivetted.
For this purpose taper rivet holes are made in the plates forming the shell
and in the angle iron to which they are rivetted. The two pieces of iron are
brought together for rivetting, so that the surface on which the holes are
smallest are in contact, and a headless rivet is introduced (from the outside of
the tube) into the holes, and it is clenched in the usual way, expanded to the
taper of the holes, thus, the finished rivet is smallest in the middle and
expands outwards each way.
My third improvement consists in facilitating the construction of masts,
topmasts, topgallantmasts, booms, gaffs, spars, and bowsprits, of wrought
iron, which may be either cylindrical or multilatiral, by inserting in the ends
of them, when such ends require fashioning to any particular shape, or
inserting into any part of the barrel where attachments or holes have to be
made, or sheaves to be inserted, pieces of wood, which immediately previously
to insertion have been reduced in size by compression, so that in their
endeavour to resume their original shape they shall tighten and firmly fasten
themselves in the iron barrel or cylinder.
By this improvement, and by the insertion of compressed blocks at intervals,
the articles enumerated will be strengthened, their shaped retained, and the
hollow parts made air-tight, so that corrosion would be prevented.
My fourth improvement consists in an improved method of arranging the
shrouds in rigging ships. In forming the shrouds of ships, it is usual for the
ropes of which they are composed to go up and pass round the mast at
the head and come down again on the same side of the ship, thus, one rope

page_text: forms two shrouds, so that if there be six shrouds on each side of the mast
then there will be six loops round the mast. Now, my Invention consists in
fastening metal cheeks to the head of the mast, through which cheeks two
pins pass, one on each side of the mast. Each shroud is made with an eye at
its end, into which fits a grooved barrel having a hole through its centre.
The eyes of all the shrouds on one side of the ship are brought between the
two cheeks, and the pin passes through the holes in the cheeks and through
the eres of the shroud and thus secures them all to the hood of the mont
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Edward Finch in the Great Seal Patent Office on the 19th
March 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
FINCH, of Bridge Works, Chepstow, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Nineteenth day of September, in the year of our
Lord One thousand eight hundred and fifty-six, in the twentieth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Edward Finch, Her special licence that I, the said Edward Finch,
my executors, administrators, and assigns, or such others as I, the said
Edward Finch, 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 CONSTRUCTION OF WROUGHT-IRON MASTS, BOWSPRITS, YARDS, BOOMS,
GAFFS, AND SPARS, AND IN RIGGING SHIPS," upon the condition (amongst others)
that I, the said Edward Finch, 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 Edward Finch, 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:-
In the construction of wrought-iron masts, bowsprits, yards, booms, gaffs,

page_text: and spars, cylindrical in shape, for large ships, it is necessary that the outer
shell should be of strong boiler plate-iron, and that at the joints the iron
should be in perfect contact. In large masts, &c. of this shape great expense
is incurred and difficulty experienced in bending the plates to the required
curve, and bringing the edges when put together in close contact with each
other, and this difficulty increases as the size of the mast, and consequently
the strength of the plates, is increased. In the construction of the above, of
small size, great difficulty is experienced in rivetting plates to the internal
Tor angle irons, or butt plates, when the diameter will not admit of a boy
getting inside to insert and hold up the rivets while they are being rivetted
from the outside. Now, my improvements consist, first, in making wrought-
iron masts, bowsprits, yards, booms, gaffs, and spars multilateral in shape
instead of cylindrical, thereby dispensing with the bending of the plates and
much facilitating the construction, and this I carry out by procuring a number
of plates equal to the number of sides determined upon, and a number of
angle irons equal to the number of angles formed by the junction of the sides.
To the angle irons I rivet the side plates, and the more effectually to bring
the plates in contact I plane both the vertical and horizontal edges of the
plates to form the joints; and to give uniformity of strength and elasticity, I
cause the plates to break joint with each other, and I weld the angle irons up
in one piece for the entire length required.
My second improvement consists in doing away with the necessity, in masts,
bowsprits, yards, booms, gaffs, and spars of small size, of putting in the rivets
from the inside, and holding them up while being rivetted. For this purpose
taper rivet holes are made in the plates forming the shell, and in the angle
iron to which they are rivetted. The two pieces of iron are brought together
for rivetting, so that the surfaces on which the holes are smallest are in contact,
and a headless rivet is introduced from the outside of the tube into the holes,
and it is clenched in the usual way to expand it to the taper of the holes, thus
the finished rivet is smallest in the middle and expands outwards each way.
My third improvement consists in facilitating the construction of masts, top-
masts, topgallantmasts, booms, gaffs, spars, and bowsprits of wrought iron,
which may be either cylindrical or multilateral, by inserting in the ends of
them, when such ends require fashioning to any particular shape, or inserting
into any part of the barrel where attachments or holes have to be made or
sheaves to be inserted, pieces of wood, which immediately previous to insertion
have been reduced in size by compression, so that in their endeavour to resume
their original shape they shall tighten and firmly fasten themselves in the
iron barrel or cylinder.

page_text: By this improvement, and by the insertion of compressed blocks at intervals,
the articles enumerated will be strengthened, their shapes retained, and the
hollow parts made air-tight, so that corrosion would be prevented.
My fourth improvement consists in an improved method of arranging the
shrouds in rigging ships. In forming the shrouds of ships, it is usual for the
ropes of which they are composed to go up and pass round the mast at the
head and come down again on the same side of the ship, thus, one rope forms
two shrouds, so that if there be six shrouds on each side of the mast then
there will be six loops round the mast.
Now, my Invention consists in fastening metal cheeks to the head of the
mast, through which cheeks two pins pass, one on each side of the mast.
Each shroud is made with an eye at its end, into which fits a grooved barrel,
having a hole through its centre. The eyes of all the shrouds on one side of
the ship are brought between the two cheeks, and the pin passes through the
holes in the cheeks and through the eyes of the shroud, and thus secures them
all to the head of the mast.
And in order that my said Invention may be most fully understood and readily
carried into effect, I will proceed to describe the Drawings hereunto annexed.
DESCRIPTION OF THE DRAWING.
Figure 1 and Figure 2 are transverse sections of a wrought iron mast, bow-
sprit, yard, boom, gaff, or spar, made according to my Invention, multilateral in
shape. a, a, a, a, are plates of sheet iron, planed on all their edges, and rivetted
to the angle irons b, b, either in the ordinary way, or by the improved method,
which I will presently describe. The size and strength of the plates a and the
angle irons 6 must be varied, according as it is desired to make a mast, bow-
sprit, yard, boom, gaff, or spar, as will be understood by those acquainted
with the manufacture of these articles in iron. Figure 3 is a portion of a
transverse section of an ordinary iron mast, bowsprit, yard, boom, gaff, or spar,
rivetted according to the second part of my Invention. a, a, are the plates
forming the shell; and b, b, are the angle irons, both of which have taper
holes puched through them, and to produce these taper holes I use a punching
machine, in which the hole in the bed die is considerably larger than the
punch. The two pieces are brought together for rivetting, so that the surfaces
on which the holes are smallest are in contact, and a headless rivet is intro-
duced from the outside of the tube into the holes, and it is clenched in the
usual way to expand it to the taper of the holes, as is shewn by the Drawing.
The third part of my Invention consists in inserting into wrought-iron masts,
topmasts, topgallantmasts, booms, gaffs, spars, and bowsprits, pieces of wood,

page_text: which immediately previous to insertion have been reduced in size by com-
pression, so that in their endeavour to assume their original shape they tighten,
and firmly fasten themselves in the iron barrel or cylinder. Sheet 2 of the
Drawings shows the machine which I use for compressing wood for this
purpose. I would have it understood, in reference to this part of my Inven-
tion, that I do not claim generally the inserting pieces of wood into the
interior of wrought-iron masts, topmasts, topgallantmasts, booms, gaffs, spars,
and bowsprits, but I claim it only when such wood has previously been
submitted to compression.
The fourth part of my Invention consists in an improved method of
arranging the shrouds in rigging ships. Figure 4 is a side view, Figure 5
a longitudinal section of a mast and shrouds, arranged according to my Inven-
tion; Figure 6 is a horizontal section, taken through the head of the mast.
a, a, is the mast, and b, b, are metal cheeks fastened to it; c, c, are pins which
pass through the cheeks; d, d, are the shrouds, each having an eye at its end;
e, e, are grooved barrels which pass through the eyes of the shrouds, and these
barrels have holes through their centres for the pins c, c, to pass through, and
so secure the shrouds to the mast head; fis the stay, which has two eyes at
its end, which passes over the barrels g, g.
In witness whereof, I, the said Edward Finch, have hereunto set my
hand and seal, this Sixteenth day of March, in the year of our Lord
One thousand eight hundred and fifty-seven.
Witness,
BENJ FINCH, of Chepstow,
Engineer.
EDWARD FINCII. (L.S.)

page_text: made so that it may be adjusted er removed at pleasure - thus die has in the centre of it a taper hole made which at the small or outer and is of the size and shape to
which the timber is required to be compressed the shape of the taper hele is shown by dotted lines. 6 is the piece of timber required to be compressed. The act of
compression is by frang out the ram C against the timber to pass through the taper hole in the due, reducing itm size and bringing it to the shape required.