IMPROVEMENTS IN BOLTING OR FASTENING ONE PART OF A SHIP OR VESSEL TO ANOTHER
Year: 1868

page_text: LETTERS PATENT to James Williamson, Lloyd's Surveyor, of 2, White
Lion Court, Cornhill, in the City of London, for the Invention of
"IMPROVEMENTS IN BOLTING OR FASTENING ONE PART OF A SHIP OR
VESSEL TO ANOTHER."
Sealed the 14th July 1868, and dated the 15th January 1868.
PROVISIONAL SPECIFICATION left by the said James Williamson
at the Office of the Commissioners of Patents, with his Petition,
on the 15th January 1868.
I, JAMES WILLIAMSON, Lloyd's Surveyor, of 2, White Lion Court,
Cornhill, in the City of London, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN BOLTING OR FASTENING ONE PART OF
A SHIP OR VESSEL TO ANOTHER," to be as follows:-
This Invention relates especially to the fastening of composite ships
or vessels, that is to say, of ships or vessels in which a frame of iron
supports a wooden planking. In such vessels as at present constructed
it is found that the bilge water or the sea water is liable to find its way
to the point where the iron frame and the copper or yellow metal bolts
are in contact, and there to cause the frame to be eaten away, and this
takes place notwithstanding that the frames and the ends of the fastenings

page_text: are covered with cement, because the adhesion of cement to wooden
planking is but imperfect.
Now according to my Invention I prevent the passage of water to the
point where it is liable to produce decay by placing around the fastening
and between the planking and the frame a washer of vulcanized india-
rubber, or of other compressible and waterproof material. This washer
is lodged in a recess countersunk around the bolt hole in the planking,
and of such a size as to be accurately filled by the washer when it is
compressed by the screwing up of the nut on the fastening. A similar
arrangement is also applicable when iron fastenings are used, and it then
serves to prevent the passage of the bilge water into the bolt hole, and
the bolt hole being thus kept dry (assuming the head of the fastening
to be properly bedded) the stem of the fastening is not liable to decay
in consequence of galvanic action resulting from the proximity of the
sheathing. Where a fastening is used to secure two pieces of timber
the one to the other as in the dead wood of a ship or vessel I introduce
a similar washer in between the two pieces of timber, and let it into a
countersunk recess in a similar way, the washer so used cuts off the bilge
water from the bolt hole, and so prevents the decay of the fastening.
Also between armour plates and their wooden backing, and between
the backing and the iron skin I interpose washers in a similar manner
and with a similar object.
SPECIFICATION in pursuance of the conditions of the Letters Patent
filed by the said James Williamson in the Great Seal Patent
Office on the 15th July 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
WILLIAMSON, Lloyd's Surveyor, of 2, White Lion Court, Cornhill, in the
City of London, send greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifteenth day of January, in the year
of our Lord One thousand eight hundred and sixty-eight, in the thirty-
first year of Her reign, did for Herself, Her heirs and successors, give
and grant unto me, the said James Williamson, Her special licence,
that I, the said James Williamson, my executors, administrators,;
and assigns, or such others as I, the said James Williamson, my

page_text: 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,
excrcise, and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN BOLTING OR FASTENING ONE PART OF A SHIP OR VESSEL TO
ANOTHER," upon the condition (amongst others) that I, the said James
Williamson, 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 James Williamson, do hereby
declare the nature of the said Invention, and in what manner the sanie
is to be performed, to be particularly described and ascertained in and
by the following statement thereof, that is to say :-
This Invention relates especially to the fastening of composite ships
or vessels, that is to say, of ships or vessels in which a frame of iron
supports a wooden planking. In such vessels as at present constructed
it is found that in consequence of the imperfect adhesion of the cement
to the wood planking the bilge or sea water is liable to find its way to
the point where the back of the iron frame and the copper or yellow
metal bolts are in contact, and there to cause the frame to be eaten
away; whereas on the other hand the inner surface of the iron frame is
preserved from this injurious action by the exclusion of all moisture
from the metal nut, which is effected by the perfect adhesion of the
cement to the ironwork.
Now according to my Invention I prevent the passage of water to the
point where it is liable to produce decay by placing around the fastening
and between the planking and the frame a washer of vulcanized india-
rubber, or of other compressible and waterproof material. This washer
is lodged in a recess countersunk around the bolt hole in the planking,
and of such a size as to be accurately filled by the washer when it is
compressed by the screwing up of the nut on the fastening. A similar
arrangement is also applicable when iron fastenings are used, and it then
serves to prevent the passage of the bilge water into the bolt hole, and
the bolt being thus kept dry (assuming the head of the fastening hole

page_text: Figure 1 in the Drawing represents a longitudinal section of a
composite ship through the floor plate of the scantlings required by
Lloyd's suggestions" for a 600 tons ship.
A represents the floor plate; B, the main angle iron frame; C, the
angle iron reverse frame; D, the wood skin or outside planking; E, the
copper or yellow metal bolt for connecting the skin or planking to the
iron frames; F, the copper or metal nut screwed upon the iron frame;
H, H, cement for protecting the rivets and the nut F. It has been
proved by experience that although the metal nut F is screwed upon the
iron frame, and may therefore be said to be in direct contact with it, the
adhesion of the cement H, H, to the ironwork if well done is so
perfect as to thoroughly protect the inner surface of the iron frame from
the deteriorating influence of the copper or yellow metal fastenings,
when aided by the action of the bilge or sea water, which goes to prove
that if I can effectually prevent the bilge or sea water from getting at
the copper or yellow metal fastenings at the junction of the outside
wood planking with the iron frames, which the inefficient adhesion of
the cement to the wood planking fails to accomplish, I shall have
thoroughly protected the back or outside surface of the iron frames from
the injurious action of such fastenings. In order to effect this desirable
object I introduce a washer I made of vulcanized india-rubber or any
other compressible water-tight material round each bolt between the
backs of the iron frames and inside surface of wood planking.

page_text: The following is a description of the manner in which it is done;
viz. The vessel being in frame, the next operation is the working of
the wood skin or planking upon the frames, and the boring out the bolt
holes in the usual way. The planks are taken down and with a tool
similar in all respects to that known in the ship-building profession as a
"dowelling engine," a small round cavity is bored out of the inside of
plank around each bolt hole to receive the washer I. The said "dowel
engine" should have a permanent stop made on it, so as to prevent the
workmen boring too deeply into the plank. This operation having been
performed to each hole in each plank, a washer of vulcanized india-
rubber or any other water-tight compressible material is next placed in
cach of the cavities made round each bolt hole, and kept in its place by
means of two small tacks or nails. The plank is then worked up against
the frames again and the screw bolt fastenings are next driven, and as
soon as the bolt points are sufficiently far through the iron frames the
nuts are screwed up, the planks will then be drawn closely to the frames.
It is recommended that the depth of the cavity in the planking be one
half the thickness of the washer, i.e., supposing the washer to be inch
thick, the cavity in the plank should be inch deep, this will allow
quarter inch of the washer to stand above the surface of the plank, which
when hove up the pressure upon the plank and frame will make a
thoroughly water-tight surface around the bolt, and thus prevent the
bilge water or any other moisture from getting at the copper or
yellow metal bolts.
The washer represented in the Drawing is 13 inch diameter and the
bolt hole in it is inch, the bolt being of an inch, and these are
convenient sizes.
As before mentioned a similar arrangement is applicable in ships in
which iron fastenings are used, and where the ship is sheathed with
copper or yellow metal. For it has been observed that in vessels so
fastened the iron bolts below the bilges decay very rapidly, and that such
decay commences from the inside of the bolt. These washers are there-
fore specially useful to keep the stem of the bolts from being affected by
the bilge water. The bolt heads may be made perfectly tight by bedding
them in white lead or driving them on a thin vulcanized india-rubber
washer as is sometimes done.
The same arrangement is applicable when iron ships are planked with
wood and sheathed with copper or yellow metal over the wood as shown

page_text: at Figure 2. a, a, are the frames of the ship; b, the iron skin; c, the
wood planking; d, the bolts with which it is fastened, and d', the
compressible washers which serve to keep the bolt holes dry, preventing
water entering them from the back, and so preserving the bolts from
decay from galvanic action.
Figure 3 shows the method in which the waterproof compressible
washers are applied according to my Invention between two pieces of
timber where a bolt passes through them. The washers are applied at
the points marked I, I.
Figure 4 shows a horizontal section of the side of an armour plated
vessel shewing the application of washers according to my Invention to
the armour bolts both between the armour and the backing, and between
the backing and the skin plates. a, a, are the ship's frames; b, the skin;
c; the wooden backing; d, the bolts which secure the backing, they are
provided with washers at d'; e, the armour plates, and f, the armour
bolts with washers at f¹ and f*.
In witness whereof, I, the said James Williamson, have hereunto
set my hand and seal, this Sixth day of July, in the year of
our Lord One thousand eight hundred and sixty-eight.
JAMES WILLIAMSON. (L.S.)