AN IMPROVEMENT IN THE FORM AND IN THE METHOD OF HOLDING AND RELEASING THE TUMBLING HOOK OF DISENGAGING BLOCKS
Year: 1859

page_text: LETTERS PATENT to James Nash, of Mill Wall, in the County of
Middlesex, Smith, for the Invention of "AN IMPROVEMENT IN THE FORM
AND IN THE METHOD OF HOLDING AND RELEASING THE TUMBLING HOOK OF
DISENGAGING BLOCKS."
PROVISIONAL SPECIFICATION left by the said James Nash at the
Office of the Commissioners of Patents, with his Petition, on the
29th June 1859.
I, JAMES NASH, of Mill Wall, in the County of Middlesex, Smith, do
hereby declare the nature of the said Invention for "AN IMPROVEMENT IN THE
FORM AND IN THE METHOD OF HOLDING AND RELEASING THE TUMBLING HOOK OF
DISENGAGING BLOCKS," to be as follows:-
This Invention consists of an improvement upon the disengaging blocks
heretofore in use, and more particularly the "safety block," for which William
Clark obtained Letters Patent, bearing date the Twelfth day of April, One
thousand eight hundred and fifty-nine, No. 910.
The first part of this improvement consists in giving a novel form to the
tumbling hook, the bill of the hook being crescent-shaped, so as to be self-
mousing, while the back of the hook, acting in combination with a vertical
sliding bolt, herein-after described, is self-fastening.
The second part of my Invention relates to an improved method of holding
and releasing the tumbling hook. In the Specification of the before-named.
William Clark, the method of holding the tumbling hook is described and
shown to consist of "a small metal plate" moving laterally on a pivot attached
to the stem of the block, this stop or ketch resting against a shoulder on one
side of the stem, and kept firmly in position by means of a "safety pin"

page_text: passed through a hole in the stem; this pin is sufficiently long to meet the
bill of the hook and form a mousing, which prevents the cord or chain
suspended from the hook from being accidentally jerked off. In lieu of
"the metal plate or ketch moving laterally on a pivot," I uso a bolt sliding
vertically on the stem of the block, which is out of the way, and not liable to
be accidentally struck up, and therefore does not require a safety pin to
secure it. From the peculiar form given to the back of the tumbling hook
when returned to its holding position, it raises the vertical sliding bolt, which
falls again by its own weight, and becomes self-fastening. On lifting the
sliding bolt by a chain or lanyard, the tumbling hook is free to turn over in
the usual manner, discharging whatever may have been suspouded from it.
SPECIFICATION filed in pursuance of the conditions of the Letters Patent,
and of an Order of the Lord Chancellor, by the said James Nash in the
Great Seal Patent Office on the 26th January 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
NASH, of Mill Wall, in the County of Middlesex, Smith, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-ninth day of June, in the year of our Lord One
thousand eight hundred and fifty-nine, in the twenty-third year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
James Nash, Her special licence that I, the said James Nash, my exe-
cutors, administrators, and assigns, or such others as I, the said James
Nash, 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 IMPROVEMENT IN
THE FORM AND IN THE METHOD OF HOLDING AND RELEASING THE TUMBLING HOOK
OF DISENGAGING BLOCKS," upon the condition (amongst others) that I, the
said James Nash, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should par-
ticularly 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 James Nash, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-

page_text: formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say:-
This Invention consists of an improvement upon the disengaging blocks
heretofore in use, and more particularly the "safety block," for which William
Clark obtained Letters Patent, bearing date the Twelfth day of April, One.
thousand eight hundred and fifty-nine, No. 910.
The first part of this improvement consists in giving a novel form to the
tumbling book, the bill of the hook being crescent-shaped, so as to be self-
mousing, while the back of the hook, acting in combination with a vertical
sliding bolt, herein-after described, is self-fastening.
The second part of my Invention relates to an improved method of holding
and releasing the before-named tumbling hook. In the Specification of the
before-named William Clark, the method of holding the tumbling hook is
described and shown to consist of a small metal plate moving laterally on a
pivot attached to the stem of the block, this plate (which is called a stop or
ketch) resting against a shoulder on one side of the stem, and is kept firmly
in position by a safety pin passed through a hole in the stem; this safety pin
is made sufficiently long to meet the bill of the book, and form a mousing,
which prevents the cord or chain suspended from the hook from being acci-
dentally jerked off. In lieu of the metal plate or ketch moving laterally on a
pivot, I use a bolt sliding vertically on the stem of the block, which is out of
the way, and not liable to be accidentally struck up, and therefore does not
require a safety pin to secure it. From the novel and peculiar form given to
the back of the tumbling hook when returned to its holding position, it raises
the vertical sliding bolt, which falls again by its own weight, and becomes
self-fastening. On lifting the sliding bolt by means of a chain or lanyard, the
tumbling hook is free to turn over in the usual manner, discharging whatever
may have been suspended from it.
And in order that the nature of my said Invention, and the manner of
performing the same may be more fully understood, reference is had to the
annexed Drawings, and to the letters and figures marked thereon.
In these Drawings, Figure 1 is a side elevation, and Figure 2 an edge
view, of a disengaging block embodying my before-named improvement.
Those parts of these Drawings which are left uncolored are parts which are
old and well known, and have been in common use in disengaging blocks long
before the date of the above-named Letters Patent; while the peculiar com-
bination of parts herein-after described, and which constitute my said improve-
iment thereon, are distinguished by being colored. The same letters refer to
similar parts in each of these two Drawings.

page_text: A is the body or shell of the block, with its sheave, constructed in the
ordinary manner; B is a forked shank or stem descending from the body of
the block, at the lower end of which is pivoted a crescent-shaped hook C, so
formed that when in its holding position the bill of the hook c' closes upon the
sbank or stem B, and forms a mousing, which prevents any ring, rope, chain, or
shackle suspended therefrom from being accidentally jerked off; D is a metal
bolt sliding freely up and down in a housing or guide e. The inner edge of
the bolt D is bevilled off at the lower end to facilitate its self-fastening when
acted upon by the back of the hook c. In Figure 1, the hook is shewn in
its holding position, being prevented from turning round in consequence of the
back of the hook being intercepted by the lower end of the vertical bolt D.
On pulling a lanyard F, the bolt D is lifted, releasing the hook C, which flies
round into the position shown by the dotted lines, and discharges whatever
may have been suspended from or held by it. On placing a ring or shackle
on the bill of the hook, and returning it to the holding position, it is self-
fastening; the back of the hook is so formed, that on striking the bevilled
edge of the vertical bolt D, it lifts and passes under it; the bolt then falls
again by its own weight, and securely holds the hook until again released by
pulling on the lanyard F. Disengaging blocks constructed in this manner
may be used for lowering ship's boats, for casting off tow ropes, as well as
many other useful purposes either close at hand or at a distance.
And having now described the nature of my Invention, and the manner of
performing the same, I desire it to be understood that what I claim as new,
and constituting my Invention of an improvement in disengaging blocks, is
the improved form of the tumbling hook, and the peculiar combination of
parts for holding and releasing the same, as herein-before described and shown
in the annexed Drawings.
In witness whereof, I, the said James Nash, have hereunto set my
hand and seal, this Twenty-sixth day of January, in the year of our
Lord One thousand eight hundred and sixty.
Witness,
W. BADDELEY,
Patent Agent,
Islington.
JAMES NASH. (L.S.)