AN IMPROVED SLIP OR DISENGAGING HOOK
Year: 1857

page_text: LETTERS PATENT to Augustus Frederick Kynaston, residing at Plymouth,
in the County of Devon, a Post Captain in the Royal Navy, Companion
of the Bath, and Kt. of the Legion of Honor, for the Invention of
"AN IMPROVED SLIP OR DISENGAGING HOOK."
Sealed the 22nd June 1858, and dated the 23rd December 1857.
PROVISIONAL SPECIFICATION left by the said Augustus Frederick
Kynaston at the Office of the Commissioners of Patents, with his
Petition, on the 23rd December 1857.
I, AUGUSTUS FREDERICK KYNASTON, residing at Plymouth, in the County of
Devon, a Post Captain in the Royal Navy, Companion of the Bath, and
Kt. of the Legion of Honor, do hereby declare the nature of the said
Invention for "AN IMPROVED SLIP OR DISENGAGING HOOK," to be as follows:-
The object of my Invention is to provide a hook which may with ease and
certainty be released from any body to which it is attached, or which is attached
to it, whether the pressure or pull exerted upon the said hook be great or
small, uniform or variable; and my Invention consists of a hook constructed
in the following manner :-I mount a hook proper upon a pin or centre which
is supported by and between two curved or other plates or guard pieces, and
by means of a second pin or centre I connect to the back of the hook proper
a link, shackle, or arm, which passes up between the plates or guard pieces,
and receives at its upper end the chain, rope, bolt, or other object to which the
hook itself is to be connected, and by which the strain put upon the hook is to

page_text: be borne. The two pins or centres are so placed, that when a strain is put
upon the hook proper, it will turn about the pin or centre in the link, shackle,
or arm until the loop, link, or eye by which the strain is put upon the hook
proper is allowed to fall or slip freely from it. To prevent this occurring,
except when it is desired to release the hook, a shifting pin or bolt is passed
through the plates or guard pieces in front of the stem of the hook proper to
form a stop to prevent the said book proper from turning as described. The
same end may be attained by placing pulleys or sheaves in the upper ends of
tho hook proper, and of the link, shackle, or arm, through which pulleys a
cord or line may be rove and made fast, either to the link, shackle, or arm, or
elsewhere. By withdrawing tho aforesaid pin or bolt in the one case, and by
loosening the line or cord in the other, the hook will be disengaged; the two
arrangements may be sometimes combined advantageously in the samo hook.
The plates or guard pieces are so formed that when the hook is supporting a
strain, the point of the hook proper lies between them, and the loop, link, or
eye by which the strain is put upon the hook is thus effectually prevented from
accidentally releasing itself.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Augustus Frederick Kynaston in the Great Seal Patent
Office on the 23rd June 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, AUGUSTUS
FREDERICK KYNASTON, residing at Plymouth, in the County of Devon, a Post
Captain in the Royal Navy, Companion of the Bath, and Knight of the
Legion of Honor, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing dato the Twenty-third day of December, in the year of our
Lord One thousand eight hundred and fifty-seven, in the twenty-first year
of Her reign, did, for Herself, Her beirs and successors, give and grant
unto me, tho said Augustus Frederick Kynaston, Her special licence that
I, the said Augustus Frederick Kynaston, my executors, administrators,
and assigns, or such others as I, the said Augustus Frederick Kynaston,
my 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, exercise,
and vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "AN IMPROVED SLIP

page_text: OB DISENGAGING HOOK," upon the condition (amongst others) that I, the said
Augustus Frederick Kynaston, my executors or administrators, by an in-
strument 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 Augustus Frederick Kynaston, do
hereby declare the nature of my said Invention; and in what manner the
same is to be performed, to be particularly described and ascertained in and
by the following statement thereof, reference being had to the Drawings
hereunto annexed, that is to say:-
The object of my Invention is to provide a hook which may with ease and.
certainty be released from any body to which it is attached or which is
attached to it, whether the pressure or pull exerted upon the said hook be
great or small, uniform or variable, and also effectually to shield its point
while supporting a strain, that it may not become accidentally disengaged;
and my Invention consists essentially of a hook constructed in the following.
manner :-
a side view of the said hook.
which is supported by and
To the back of the hook
shackle, or arm d, which
Figure 1 of the Drawings hereunto annexed is
The hook proper a is mounted upon a pin a',
between the curved plates or guard pieces b, b.
proper a is connected by a second pin c, a link,
passes up between the plates or guard pieces 6, 6, and receives at its end c the
chain, rope, bolt, or other object to which the hook itself is to be connected,
and by which the strain put upon the hook a is to be borne. The two pins or
centres a and c are so placed, that when a strain is put upon the hook a, it
will turn about the pin or centre c in the link, shackle, or arm d until the loop,
link, or eye A, by which the strain is put upon the hook a is allowed to fall or
slip freely from it. To prevent this occurring, except when it is desired to
release the hook, a shifting pin or bolt f is passed through the plates or guard
pieces b, b, in front of the stem 6' of the hook a, to form a stop to prevent the
said hook from turning as described. The same end may be attained by
placing pulleys or sheaves 9, 9', in or near the ends of the hook stem 6', and of
the link, shackle, or arm d, round which pulleys a cord or line h may be rove
as shewn, and have its ends made fast to other cords or lines, or to any other
objects, according to the purpose to which the hook may be applied. By
withdrawing the aforesaid pin or bolt f in the one case, and by loosening the
cord or line h in the other, the hook a will be disengaged. The two arrange-

page_text: ments may be sometimes combined advantageously in the same hook. The
plates or guard pieces b, b, are so formed that when the hook is supporting a
strain, the point of the hook a lies between them or just clear of them, and the
look, link, or eye A, by which the strain is put upon the hook a is thus
effectually prevented from accidentally releasing itself. In order to facilitato
the making fast of the line h to the hook itself, I pass a pin p through the curved
plates or guard pieces b, b, which pin projects upon each side, so that it may bo
used as a belaying pin.
In Figure 2 of the Drawings hereunto annexed, I have represented a hook
of the same kind and dimensions as that shewn in Figure 1, but in Figure 2
the parts of the hook are shewn in the positions which they assume when tho
pin f has been withdrawn, or the line h let go, and the loop A has thus been
released from the book proper a.
My improved hook may be applied to numerous purposes for which slip or
disengaging hooks have been or may be found useful, but the most important
of its applications is that of disengaging boats from their tackles when lowered
in a seaway or elsewhere, and again connecting them for hoisting up, both of
which operations may by its aid bo effected with great additional ease and
security by the mere assistance of a single line. For this purpose two of my
improved hooks are employed, one at each end of the boat, as illustrated in
Figure 3 of the Drawings hereunto annexed. In this Figure A, A', are the
lower blocks of the tackles by which the boat is suspended from the davits,
and which have ordinary eyes or thimbles B, B', (and in some cases shackles
or rings attached to the thimbles) to receive the hooks proper a, a', of my
improved books. The lower ends e, e', of the links or armis d of the improved
hooks are connected by shackles i, , to the ordinary rings k, k, through which
the suspending boat chains 1, P, are passed, these chains being made fast to.ring
The
or eye bolts driven and clenched through the boat in the usual manner.
boat's steadying lines may be secured to the shackles on the lower ends of the
links or arms, or to eye bolts rivetted to the latter. The hauling parts of the
line h, h, are severally passed through single sheave blocks m, m', at the
opposite ends of a short length of rope n, and are thence led to cleats o, o', at
or near the ends of the boat. The parts being arranged as shewn in Figuro's
the disengagement of the boat is effected in the following manner :-The pins
ff, are first withdrawn, and in order to facilitate their withdrawal, the strain
or pressure of the hook stems b, b, upon them is removed by means of small
tackles hooked into the eyes or thimbles ", h, formed for the purpose in
the ends of the standing parts of the lines h, h', and bauled upon by a man or
men in a boat. The pins f. f', being withdrawn, it only remains to let go

page_text: either one or other, it does not matter which, of the lines h, h', from the cleats
o, o, and the hooks will both be instantly and simultaneously released from the
eyes or thimbles B, B', of the blocks A, A. The additional security obtained
in the process of reconnecting the boat to her tackles above that obtained
with the common hook arises chiefly from the "guards," which prevent the
tackle, after being once hooked on, from becoming accidentally disengaged by
the waves or by the motion of the vessel.
And having now described the nature of the said Invention, and in what
manner the same is to be performed, I declare that I do not confine myself to
the precise details herein set forth, as they may be varied without departing
from the essential features of my Invention; but that I claim the construction
of a slip or disengaging hook, essentially as herein-before described, und
represented in the Drawings hereunto annexed.
In witness whereof, I, the said Augustus Frederick Kynaston, have
hereunto set my hand and seal, this Nineteenth day of June, One
thousand eight hundred and fifty-eight.
A. F. KYNASTON. L.S.)