IMPROVEMENTS IN BOAT LOWERING AND DETACHING APPARATUS
Year: 1874

page_text: PROVISIONAL SPECIFICATION left by George Blake and Robert
Tompkins at the Office of the Commissioners of Patents, with their
Petition, on the 16th September 1874.
We, GEORGE BLAKE and ROBERT TOMPKINS, both of Reading; in the
3.County of Berks, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN BOAT LOWERING AND DETACHING APPARATUS," to be as
follows:-
The objects of this Invention are so to construct boat lowering and
detaching apparatus that the boat may be lowered with ease and safety,
and shall be detached from its suspending gear or tackle immediately the
boat, or rather the middle part of same, enters the water, and at the
same time, so that it may be lowered from deck or from the boat itself.
For this purpose we employ two davits, each consisting of an upright
post or stanchion, on the top of which there is a horizontal bar, part of
which runs inboard and part projects out from the ship, the part outside

page_text: the side of the vessel is hinged on so that it may be swung inboard
when not in use.
The boat when inboard is suspended from a shaft resting on the other
or inner part of the said horizontal bars. These bars are so formed, by
preference, in a cannelled or U shaped from, one or both sides of which
form rails, that travelling wheels may run thereon, which wheels are
on the aforesaid shaft from which the boat is suspended. In order to
insure against canting or jamming, when running the boat in and out,
the davits may have racks, and the shaft corresponding tooth wheels.
This shaft has at each end between the davits a winding drum fixed on
to it. The ropes for hoisting and lowering the boat are coiled round those
drums, one end of each rope being fixed to an eye or hook on a frame
suspended loosely from the shaft. The rope from one of these winding
drums passes to a winch or block which can be worked from deck. One
of the winding drums has a toothed wheel, which by gear is connected
to a pendulum check pawl appliance for lowering from the boat itself,
independently of the winch on deck, and for checking or regulating the
speed of lowering. The pendulum is held by a string which when
untied from some point of attachment on the boat allows the lowering
to take place.
For detaching the boat we prefer to use the following arrangement :-
The bight of the suspending rope at each end of the boat is passed
round double hooks, one within the other, each turning on its fulcrum,
but the outer or upper one forming part of a double armed lever whose
other lower end, by a rod running along each side of the boat, is con-
nected to a catch at each side at or near the middle of the length of the
boat. There are thus two catches for each double hook or suspending
point. These catches hold between them two and two the two blocks
which by means of bell-crank levers or other well-known mechanical
connecting appliances are in communication with two floats or buoys
arranged in chambers on each side of the keel about midway of the
length of the boat.

page_text: between the aforesaid catches will be raised free of the catches, which
then, aided by springs or weights, will fly out at their lower arms
or ends, and by the rod and lever connections aforesaid open the double
hooks.
Weights or anrings may be used instead of the brows homin doceribed