On Launching Vessels whose Bottoms are coppered on the Stocks. --
Ships are frequently built at places where there are no dry docks, nor even
any convenient place for laying them on the ground, so as to get the cleats,
which are nailed on the bottom for securing the heads of the proppets, &c.
belonging to the bilge-ways taken off; in which circumstance, if the vessel is
to be coppered, it must be done upon the stocks. In this case, you must attend
strictly to the caulking. The whole bottom must be carefully examined and made
perfectly tight, and the coppering completely finished, before preparing for
launching; and lastly, the launch must be so contrived that every thing
connected with the bilge-ways shall stand independent of any fastening or
cleats to the vessel's bottom, which would destroy the copper. There are two
or three ways by which this may be effected -- as by binding the heads of the
proppets by chains passing from the one side to the other, under the bottom,
connecting them in such a manner that they can be disengaged when the vessel
reaches the water, to allow all the launching material to be hauled from under
the bottom. To do this properly, you must nail a stout piece of plank along
the heads of the proppets outside and in; bore a few auger-holes through these
planks; also have locking-pieces on the outside of the planks, and through
these holes pass a chain doubled, so that the bight of the chains from either
side may meet at the keel; put the double of the one chain up through the
bight of the other from the opposite side; haul them tight, and put a bolt
through the
The proppets and bilge-coads may be also from flying out, by nailing a
stout ribband along, to prevent them from flying forward or aft from the
inclined surface of the bottom, and fixing 3 or 4 stout ring-bolts in the
bilge-coads at the upper and lower end, the foremost one opposite the foremost
proppet or so, and the aftermost one at the lower end of the bilge-ways,
opposite the aftermost proppet. Put ring-bolts through the ship's bow and
quarters above water-mark, right above those on the bilge-coads; the
ring-bolts for the vessel's bow and quarters must have their heads made in
form of a crook or dog-bolt for a windlass, the crook being about 1½ or
2 inches in length, and very strong at the neck; the rings must also be
strong, and pretty large in diameter. When the bolts are driven in through and
locked up properly on the ceiling, and the ring-bolts in the bilge-coads
locked on the inside of the same, procure a few stout pieces of timber for
wrung-staffs, of sufficient length to reach from the ring-bolt in the
bilge-coad up through the ship's quarters; and having put one end into the
ring at the bilge-coad, and the other up against that in the vessel, slip on
the ring over it and the crook. Having secured three or four of these on each
bow and quarter in the same manner, fasten a stout piece of timber on their
inner sides, and opposite to the plank or ribband on the heads of the
proppets; then between these set in short pieces of timber for shores, and
wedge them all tight up, which will completely prevent the heads of the
proppets f[r]om flying out when they receive the weight of the vessel. The use
of having the ring loose from the bolts, and to ship on the crook of the bolts
through the vessel's side, is, that it may be easily unhooked, and allow the
wrung-staffs to be disengaged. These rings must be fastened to the end of a
small piece of cord, to prevent their being lost by falling into the water
when they are tripped off the crook by the floating up of the vertical pieces,
along with the bilge-coads, proppets, and other timber employed for the
filling-up of the launch.
Lastly, the heads of the proppets may be secured from flying out, by first
laying two or three short logs of timber twartship-ways, with their ends under
the vessel's keel, and the other projecting out over the top of the bilge-coad
for 5 or 8 feet. From the outer end of these, diagonal shores may be placed
against the ribband on the head of the proppets, which of course will
completely prevent them from flying out by the pressure of the vessel. Transcribed by
Lars Bruzelius
Sjöhistoriska Samfundet | The Maritime History Virtual Archives.
© Copyright 1997 Lars Bruzelius.
Peter Hedderwick: A Treatise on Marine Architecture, containing the theory and practice of shipbuilding, with rules for the proportions of masts, rigging, weight of anchors, &c including Practical Geometry and the Principles of Mechanics; observations on the Strength of Materials, Hydrostatics, &c. with many valuable tables calculated for the use of shipwrights and seamen; also the proportions, scantlings, construction, and propelling power of steam-ships. Illustrated with twenty large plates, containing plans and draughts of merchant-vessels from fifty to five hundred tons, with mast and rigging plans; plans and sections of a steam-boat of eighty-horse power; and eight quarto plates of diagrams, &c., by Peter Hedderwick.
Printed for the Author, Edinburgh, 1830. pp 342-343.