IMPROVEMENTS IN APPARATUS FOR LOWERING SHIPS' BOATS
Year: 1873

page_text: PROVISIONAL SPECIFICATION left by William Stirling Lacon at the
'Office of the Commissioners of Patents, with his Petition, on the
16th January 1873.
I, WILLIAM STIRLING LACON, of the Union Club, in the County of
Middlesex, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN APPARATUS FOR LOWERING SHIPS' BOATS," to be as
follows:-
This Invention has for its object to provide an efficient arrangement
of apparatus for lowering boats from ships, either when they are under
way or are stationary. For this purpose the boats aro suspended from
the davits by two ropes or chains attached to them near their bow and
stern ends. The ropes or chains are led under and over three or more
sheaves at the outer end of the davits, and from there are led over and
wound around a roller (or three drums connected together) mounted in
suitable bearings on board the ship or vessel. To the centre of this
roller is attached a rope which as the boat is being lowered will be
wound up on the roller, as the chains or ropes from the boat are un-
wound from it, and the lowering of the boat is controlled by a man paying
out this rope and by it governing the speed at which the roller can turn,

page_text: The boat is hoisted up by the ordinary tackles hooked on to an eye
bolt at the outer end of the davits, and after the boat is raised the
chains or ropes passing from it and over and under the sheaves on the
davits are wound up on the roller which is on board the ship, the rope
which has been previously wound round the centre of the roller being
gently hauled on to revolve the roller. When the boat has been
hoisted and secured by these means the centre rope is belayed round
a belaying pin or cleat and the hoisting tackles are unhooked and
removed.
For lowering the boat a man disengages the centre rope from the
belaying pin or cleat, and as the weight of the boat then causes the
roller to turn and to wind up the central rope upon it the man by
holding on to the rope controls the speed at which the roller can turn,
and thereby controls the lowering of the boat.
The ropes or chains by which the boat is slung are of sufficient length
to pass from the roller over the davits and to the boat after it has been
lowered. If the ship is not under way, and the boat when lowered
is alongside, the chains are quietly lowered down into the boat by
small lead lines attached to their ends, such lead lines having previously
been wound upon the rollers in the same way as the chains or ropes. If
when the boat is lowered the ship has way upon her the boat will
drag away the chains or ropes and the light lead lines at their ends,
and as the boat drops astern they will fall harmlessly into the water.
They can now be drawn into the boat where they will act as ballast.
Or if the boat is going away for any length of time the chains can be
unshackled from the boat and be left on board the ship.
In the case of small boats of light weight the friction sheaves on the
davits may be dispensed with (one sheave only being necessary) and
the boat be similarly lowered by a man gradually paying out the central
rope which is around the roller on board the ship (this rope being held
around a belaying pin or cleat), the man holding on to the rope is thus
able to put sufficient friction on the rope to support the boat.