AN IMPROVED SAFETY BOAT LOWERING AND DETACHING APPARAtus
Year: 1872

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane,
in the County of Middlesex, Patent Agent, for the Invention of
"AN IMPROVED SAFETY BOAT LOWERING AND DETACHING APPARAtus."―A
communication from abroad by Christian Christopher Quaritius, of
Canarsia, in the County of Kings, and State of New York, United
States of America.
PROVISIONAL SPECIFICATION left by the said Alexander Melville
Clark at the Office of the Commissioners of Patents, with his
Petition, on the 14th March 1872.
I, ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, do hereby declare the nature of
the said Invention for "AN IMPROVED SAFETY BOAT LOWERING AND DETACHING
ADDARATIs "to be as follows.

page_text: connection with the detaching bolts for pulling them out when the boat
strikes the water or just before, and a drum with a friction brake in the
boat, whereon the bight of the "fall" rope between the pulley tackle
is wound, for paying off therefrom sufficient rope under the control of
one in the boat to let it down by the friction brake all as herein-after
described. The drum for paying out the fall rope to let the boat down
is arranged at the bottom of the boat amidships, with a notched disc
thereon for engaging the fall rope so that it will readily disconnect
from the drum at the proper time. The drum has a ratchet wheel on
one end and a pawl for holding the fall rope until everything is ready
for lowering, and a friction brake is also provided to regulate the descent
of the boat. The lower pulley blocks are detachably connected to the
boat at both ends by means of bars fixed to the blocks and fitting into
mortised blocks or pockets on the boat, in which they are locked by
pins attached to stop chains by which the pins are withdrawn to discon-
nect said pulley blocks when the boat falls upon the water.
Instead of having a separate fall rope. for each set of pulley blocks
with one end attached to the lower block as in ordinary arrangements,
one long rope is employed extending through both the lower blocks.
and through guide pulleys on the davits from one set of blocks to the
other. This rope is doubled between said blocks and wound on the
drum, whilst the boat is held up by the stop chains as hereafter
described, so that said rope may be slackened off for letting the boat
down after the chains have been released, and the boat is again sus-
pended by the rope, the ends of said rope being made fast to belaying
pins on the davits. The stop chains are then shortened up so as to pull
out the pins just previous to the arrival of the boat upon the surface of
the water. The boat is first hoisted up by the rope and pulleys, the
lower blocks being connected to the boat by the bars and pins before
described (the stop chains being let down sufficiently for the purpose),
then the stop chains are hooked on to hooks in the boat and the rope
slackened up to let the boat be suspended entirely by the chains, and
release said rope so that it may be hooked on to the drum. It is then
wound double thereon, being drawn through both sets of blocks, until
a sufficient amount has been taken on to let the boat down. The ratchet
wheel and pawl then hold the drum with the rope on it, so that by
pulling up the boat at the ends the boat is lifted off the chains, then said

page_text: rope is made fast to the belaying pins, and the boat is wholly suspended
on the rope, allowing the stop chains to be shifted and adjusted to detach
the pulley tackle from the boat when it falls.
When all is ready the pawl is lifted from the ratchet wheel by some
one in the boat, the rope then unwinds from the drum and lets the
boat down fast or slow according to the will of the operator who
regulates it by the brake, and soon after the blocks become detached
as before described the rope will escape from the drum and all will be
free.
It will be seen that this arrangement has the advantage of being
entirely under the control of the person in the boat, and the rope pays
out alike for both ends of necessity, so that there is no danger of either
end falling before the other, also that the complete detachment of the
boat is insured.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexander Melville Clark in the Great Seal Patent
Office on the 13th September 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent, send greeting.
WHEREAS. Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourteenth day of March, in the year
of our Lord One thousand eight hundred and seventy-two, in the
thirty-fifth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto 'me, the said Alexander Melville Clark, Her special
licence that I, the said Alexander Melville Clark, my executors, admi-
nistrators, and assigns, or such others as I, the said Alexander Melville
Clark, 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 Inven-

page_text: Figure 1 is a longitudinal sectional elevation of a suspended boat and
an elevation of the tackle; Figure 2 is a transverse section of the boat;
Figure 3 is a partial elevation of the drum for the "fall" rope; Figure 4
is a section of the same on the line x, x, of Figure 2; Figure 5 is a 3
longitudinal sectional elevation; and Figure 6 a transverse sectional
elevation showing a modification of the boat detaching apparatus.
Similar letters of reference indicate corresponding parts.
A is the boat; B, the davits; C, the pulley blocks; D, the fall rope;
E, the bars; and F, the pins by which the lower pulley blocks are 3

page_text: detachably connected to the boat by means of mortised blocks or
pockets G. H represents the stop chains for pulling out the pins to
disconnect the pulley blocks when the boat falls upon the water. 'I re-
presents the drum in the boat for paying out the fall rope to let the
boat down. K is a notched disc thereon for engaging the fall rope, so
that it will readily disconnect from the drum at the proper time. L is
a ratchet wheel and M a pawl for holding the fall rope until everything
is ready for lowering, and N is a friction brake to regulate the descent
of the boat.
Instead of having a separate fall rope for each set of pulley blocks
with one end attached to the lower block, as in ordinary arrangements,
one long rope is employed extending through the lower blocks and
guide pulleys O from one set of blocks to the other.
This rope is
doubled between said blocks, and wound on the drum I, when the boat
is held up by the stop chains as hereafter described, so that said ropé
may be slackened off for letting the boat down after the chains have
been released, and the boat is again suspended by the rope, said rope
being made fast to the belaying pins P, as shown in Figure 2, at which
time the stop chains are shortened up, also as shown in Figure 2, so as
to pull out the pins just previous to the arrival of the boat upon the
surface of the water. The boat is first hoisted up by the rope and
pulley, the lower blocks being connected to the boat by the bars E and
pins F, the stop chains being let down sufficiently therefor; then the
stop chains are hooked on to the hooks Q, and the rope D slackened up
to let the boat be suspended by them to release said rope, so that it may
be hooked on to the drum I between said blocks, as shown in Figure 3.
It is then wound thereon, being drawn through both sets of blocks until
a sufficient amount has been taken on to let the boat down.. The
ratchet wheel and pawl then hold the drum with the rope on it, so that
by pulling up the boat at the ends the boat is lifted off the chains;
then said rope is made fast to the pins P, and the boat is wholly
suspended on the rope allowing the stop chains to be shifted and
adjusted, as shown in Figure 2, to detach the pulley tackle from the
boat when it falls.
;
When all is ready, as shown in Figure 2, the pawl is lifted from the
ratchet wheel by the person in the boat; the rope then unwinds from
the drum, and lets the boat down, fast or slow, according to the will of

page_text: drum and all will be free.
It will be seen that this arrangement has the advantage of being
entirely under the control of the person in the boat, and the rope pays
out alike for both ends of necessity, so that there is no danger of either
end falling before the other; also that the complete detachment of the
boat is ensured.
The modification represented in Figures 5 and 6 consists in having
the drum I arranged on the vessel instead of on the boat, which may in
some cases be preferred, so that the control of the lowering and detaching
of the boat may be had by some one on the deck of the vessel, leaving
those being lowered in the boat free from the care of it.
In this case
the guide pulleys O will be shifted from the position in which they are
represented in Figures 1 and 2, and placed on the vessel, as shown in
Figures 5 and 6, or as may be preferred. This arrangement will save
the necessity of having the fall rope disconnected from the disc K of the
drum, as in the other case, and it will also save the suspending of the
boat on the chains to slacken the fall rope D, and connect the bight of
it to the drum I after the boat is raised, and it affords a means of
raising the boat by winding the bight of the rope on the drum.
Having described the nature of the Invention, and in what manner
the same is to be performed, I declare that what I claim as the In-
vention to be protected by the herein-before in part recited Letters
Patent is,
-
1st. The hoisting rope D extended from one set of pulleys to the other
through guide pulleys O, and combined with a drum I in the boat to be
lowered, said drum being provided with a tripping and holding device
and a friction brake, all substantially as specified.
2ndly. The combination of the hooked notched disc K with the drum
and rope D, substantially as specified.
3rdly. The bars E, pins F, pockets G, and stop chains H combined
with the pulley tackle and the boat, and constituting a detachable
connection of said blocks with said boat, all substantially as described.

page_text: 4thly. The said drum I arranged on the vessel and in connection with
the hoisting and lowering gear, substantially as represented in Figures 5
and 6.
In witness whereof, I, the said Alexander Melville Clark, have
hereunto set my hand and seal, this Thirteenth day of September,
in the year of our Lord One thousand eight hundred and
seventy-two.
Witness,
JAS. O. DEWEY,
53, Chancery Lane,
London.
A. M. CLARK. (L.S.)