IMPROVEMENTS IN BOAT DISENGAGING GEAR
Year: 1881

page_text: PROVISIONAL SPECIFICATION left by the said Mark Heaton Robinson at
the Office of the Commissioners of Patents on the 17th August 1881.
MARK HEATON ROBINSON, of Hampton Wick, in the County of Middlesex.
"IMPROVEMENTS IN BOAT DISENGAGING GEAR."
This Invention relates to improvements on a certain boat disengaging gear
invented by me, and now in use in Her Majesty's navy and elsewhere.
The gear as at present fitted is applicable only to boats suspended by chain
slings, such as are generally used in the quarter boats of Her Majesty's ships, each
sling consisting of a chain hooked or shackled at one end to a point in the keel of
the bout, and at the other to a point near the upper part of the stem or stern post,
as the case may be. The frame of the apparatus forms the connection between the
two parts of the chain sling, riz., the part which goes downwards to the keel, and
the part which goes more or less horizontally to the stem or stern post, and it is
connected to those parts respectively by shackles. one from the lower and the other
from the upper end of the frame. A ring attached to the lower block of the fall
engages with the tumbling hook which turns upon a pivot in the frame, both ends
of the said. pivot being provided with eyes to which the steadying lines are
fastened. The shank of the hook is slightly longer than and reaches below the
level of the point or tongue of the hook, and when the hook is in use points
approximately downwards. Below this in the same frame is pivotted a lever, the
short end of which presses-against the lower end of the shank of the hook so long
as the long end of the said lever is held by a retaining chain. The retaining
chains from the apparatus at the two ends of the boat are connected by a pair of
blocks and a line forming a purchase. When the fall of the purchase is hauled
tant and belayed or held, the short or upper ends of the levers are pressed (by the
pull of the retaining chains upon their lower ends) against the shanks of the hooks,
and the hooks are unable to "tumble." But when the fall of the purchase is

page_text: slacked the levers permit the shanks of the hooks to escape, and the hooks
* tumble " and release the rings of the lowering tackles simultaneously.
The
general arrangement of the slings and of the retaining chains and purchase, and the
connection between the slings and the frame containing the tumbling hooks, is
shown in the after and central parts of the boat delineated in Figure 1. The
apparatus as now used is also fitted with an appliance for mousing the hook
against accidental unhooking, consisting of two plates, one on each side outside the
frame containing the hook. These plates are rigidly connected with each other,
first, by a rivet, and secondly, by a bolt which passes through the frame, and
serves as a pivot upon which the mousing plates are able to turn through about
the half of a circle, according as it is desired to place them either in or out of
action. As the mousing plates stand necessarily some distance apart (about two
inches) the point or tongue of. the hook is flattened out spoon shape, that it may
the better fill up the space between them and render the "imousing
more efficient.
In fitting the apparatus in a boat it is desirable so to proportion the slings that
the pivot on which the hook turns shall be below the level of the gunwales, so
that the steadying lines which are attached to the ends of the said pivot, and also
to the gunwales of the boat, shall suspend the apparatus and the slings with it
when the boat is not borne by the hooks.
In order that the lever of the apparatus may have room to work when thus
sunk below the level of the gunwales, it is necessary in boats where the thwarts
and other fittings are not at a considerable distance below the gunwales (as they
usually are in a man of war's quarter boat, but not in other boats), to make special
arrangements to obtain room for the levers by cutting away parts of the thwarts
or platforms, if. there be any; or if there be air cases, by sinking hollow castings
into them into which the lever, &c., may descend.
My present improvements have for their object to render gear of this nature
more compact, so that less depth may be occupied, and that it may be fitted to any
boat at present hung by slings without reference to the position of the thwarts.
Also to arranging the gear in such manner for extreme cases that the slipping
action shall be entirely above instead of below the point of support (i.c., the point
to which the steadying lines are attached), so that it shall be applicable without
altering the fittings of the boat, even where those fittings, such as air cases or
gratings, rise up almost to the level of the gunwales. Also to arranging the gear in
such manner that it shall be applicable to boats suspended by one point only at
each end and not by chain slings. Also to providing a better mousing than that
heretofore employed to prevent accidental unhooking, which shall be smaller,
lighter, and better protected from injury. Also to providing a cheaper and simpler
suspending hook for unhooking by hand only without slipping gear, for use in the
boats of harbour ships, or in other boats to which it is for any reason considered
needless to apply simultaneous releasing gear. Such hand worked hooks share
with my other apparatus herein before referred to the advantages, first, of being at
all times supported in a convenient position for hooking on or unhooking, so that
the man charged with that duty does not require to hold up or support the hook
with one hand while hooking on the fall with the other, but has both hands free
for the management of the fall; and secondly, of being efficiently moused against
the danger of accidental unhooking. Such hand worked hooks are also adapted
both for attachment to slings and to single points of support.
The following is a description of my improved apparatus:
In Figure 1 a boat is shown (for the sake of variety in illustration) suspended at
the after end by the improved apparatus, shown in detail in Figures 2 and 3, and
at the fore end by that shown in Figure 5. A, B. are chains constituting (with
the apparatus connected with them, which is in effect one link in the chain) a
span sling" of the kind used in the navy; C is a fixed bolt rivetted on the
underside of keel, and passing up through a thwart D. Its head, which stands
above the thwart, is connected with the apparatus in the manner shown in
Figure 5; H, H, are rings (preferably the iron straps of the blocks extended down-
66

page_text: wards to form rings) attached to the lower blocks of the falls or lowering tackles,
which may be of any description commonly used which stand athwart the boat,
and are therefore seen edgeways in the Drawing, these rings engage with the
hooks of the apparatus, and the action of the latter is to release them simultaneously
at any desired moment. To each apparatus is connected (either by hooks or by
shackles at or near J, J), the chain or wire rope E, E, which is divided in the
middle by the purchase F, F. So long as the chains E, E, are stretched taut by
the purchase, the hooks of the apparatus are kept in the position shown in the
Drawings, but immediately upon the full G of the purchase being let go by the
person in charge of the boat, the slacking of the chains E, E, permits the hooks to
revolve (or "tumble") in the manner presently explained in the description of
Figure 2, and both rings are released simultaneously, thus disengaging the boat
from the ship.
The apparatus, as shown in Figures 2 and 3, which is the kind most generally
suited for cases in which the boat is hung by "span slings" (as at the after end of
the boat in Figure 1) consists of two plates K, K, held at about one inch apart by
rivets L, L, L, L, which rivets form also stops for some of the working parts. The
upper end is connected by the shackle M (which works upon the pin 0) with the
chain A, which leads to the stem or stern post, as the case may be. The lower end
is similarly connected by the shackle N working upon the pin P, with the chain B
leading to the keel. The pin O, as shown in Figure 3, has an eye at each end.
The steadying lines are attached to these eyes, and serve to suspend the apparatus
in a proper position for slipping if at any time the boat becomes waterborne
before it is released from the ship. The slings are, if possible, so proportioned that
even when the boat is suspended by the apparatus the eyes of the pin O shall be
below the level of the gunwales, to which the other ends of the steadying lines are
attached.
in
The pin forms also a pivot, upon which works upon the two plates K, K, the
curved bar Q, which is able when released to rotate through about half a circle, co
ns to turn itself upside down and completely free the ring H. As shown
Figure 2, it is prevented from rotating by the catch R, which is held to its work
by the wire rope (or chain may be used) T, T. A few inches from the apparatus, T
is spliced or shackled to a small ring, to which the chains or ropes E, E, (sec
Figure 1) are attached. When E is slacked T is slacked also; R is permitted to
travel until the projection at its large end clears the corresponding end of Q, and Q
being caused to rotate by the pull of the ring H allows the ring to slip off the
point as it rises and to go free. The apparatus then remains suspended by the
steadying lines ready for hooking on again. S is the pin on which R works: V is
a hole in each of the two plates K, K, through which a pin, called a safety pin, cau
be passed when desired to prevent the catch R from moving, notwithstanding that
the rope or chain T be slacked. The safety pin is secured to any convenient part
of the apparatus by a small chain to prevent it from being lost. W is a roller for
the rope or chain T to pass over; X, another roller for the same purpose; Y is a
tumbler, which when in the position shown mouses the hook formed by the
point of the bar Q and the front of the plates K, K, and prevents the ring H from
becoming unhooked accidentally. At the same time it does not interfere with the
releasing action of the apparatus, as above described. If it is desired to clear the
hook, either for the purpose of unhooking by hand, or of hooking on, the tumbler
can be thrown back towards the catch R, so as to be out of the way and to leave
the hook unmoused; Y remains in either position by its own weight, resting upon
une or the other of the two neighbouring rivets L, L, as the case may be; it
revolves upon the pivot 7. When thrown out of action it is accessible through the
large holes shown in the plates K, K, and can be readily pushed by the finger from
one position to the other, its outer edges being notched to facilitate this, and the
pivot Z being a very loose fit to it.
"
In Figure 3 the ring H is shewn by dotted lines only.
"
In Figure 4 is shewn another apparatus, also adapted for span slings, suitable in

page_text: cases where it is desired to keep the steadying lines lower, or where for any reason
it is inconvenient to have the catch R working below the level of the chain which
leads to the stem or stern post. In this apparatus the working parts concerned in
the releasing action are exactly the same as in Figure 2, and bear the same letters
of reference, but the plates K, K, differ so as to admit of the shackle connecting
the apparatus with the chain A (leading to the stem or stern post) being attached
at the lower rear corner of the apparatus instead of to the pin O at the top. The
pin P is furnished with an eye. at each end to receive the steadying lines instead of
the pin 0, so that the working parts of the apparatus now lie entirely above the
steadying lines. The arrangements for mousing and clearing the hook are exactly
as in Figure 2.
The pin can be made the point of attachment for the steadying lines if for any
reason it is desired to keep the slipping action lower than in Figure 4, but not so
low as in Figure 2.
Another apparatus is shown in Figure 5. This is adapted for attachment by its
lower end only to a single fixed bolt rivetted through the keel. Here the slipping
and mousing arrangements are exactly as in Figures 2 and 4, and the same letters
of reference apply; but the plates K, K, differ, and the attachment to the boat,
instead of being by shackles and chains,. is as follows:-a is a round bolt which
passes through the keel, and is rivetted below it as usual. It passes up through
and is steadied by any convenient thwart, air case, or other similar fitting in the
bont, and ends in a head b immediately above such thwart, &c. The horizontal
section of bis square or oblong, fitting loosely in between the lower ends of the
side plates K, K, of the apparatus. Across the top of b, athwartships of the boat,
is a deep groove loosely fitting to one of the rivets L of the apparatus. At c is a
hole through b, and also through the plates K, K. A pin is passed through c, and
connects together the apparatus and the head of the bolt. As the head of the bolt
enters between the plates the apparatus cannot fall either way laterally. Neither
can it fall either way in a fore and aft direction, being held up by the rivet L
coming in contact with the sides of the groove in which it lies. The apparatus is
therefore always in an upright position, and ready for hooking on or for unhooking
by hand, if need be, without requiring to be held up. The pin which passes
through may be of any convenient pattern, either a screw pin passing freely
through and through one of the plates K, but threaded to screw into the other
plate K; or such a pin as will pass freely through all the three holes, if held in a
certain position, but secured against accidental withdrawal by a projection on one
of the plates K, which enters first a longitudinal and then a circumferential groove
in the pin, with an action somewhat similar to what is known as a bayonet joint.
The pin should be attached by a chain to the thwart, or to any other convenient
point to avoid loss.
Instead of the bolt a having a head standing up above the thwart, as in Figure 5,
the upper side of such head may stop flush with the upper side of the thwart, and
the groove in which L lies may be omitted. On each side of the bolt head there
may be an opening in the thwart through which the two lower ends or tails of the
plates K, K, may be dropped, such ends or tails being made longer than in Figure 5.
The hole c through the head of the bolt and through the tails of K, K, will then
come below the thwart instead of above it, connection being still made by a pin, as
above described. The apparatus will be sufficiently steadied by contact with the
thwart at the place where it passes through it.
In cases where it is unnecessary ever to remove the slipping gear from the boat,
the apparatus may be permanently secured to the head of the bolt a.
In
Figures 6, 7, 8, 9, 10, 11, and 12, show other varieties of apparatus designed for
unhooking by hand only, and not constructed to disengage simultaneously.
these the hook is self sustained and does not require to be held up while the
process of hooking or unhooking is being performed, and a mousing is provided
similar to that shown in Figures 2 to 5. In Figures 6 and 7 are shown two
varieties of such apparatus adapted for use with span slings, and corresponding in

page_text: the method of attachment to the slings and steadying lines with the apparatus
shewn in Figures 2 and 4. The letters of reference are the same as in Figures 2
and 4; K, K, K, however representing in one forging both the frame K, K, of the
former Drawings and the bar Q, the hook in Figures 6 and 7 being a standing one
and not a tumbling one. The mousing tumbler works in a slot in the substance
of K, K, K, and can be moved at discretion either into the position shown in full
lines (and marked Y) when the hook is moused, or into that shown in dotted lines,
when it lies entirely towards the back of the apparatus and is out of action. It
lies in either position by its own weight resting upon the bottom of the slot, and
it is readily changed from one to the other. It is made of less breadth than the
slot, and it is thickest at the point where the pivot Z passes through it, so that its
other parts shall not come in contact with the sides of the slot. In Figure 6 the
stendying lines are to be attached to the double eye bolt O, and P has no other
function than to connect the hook with the shackle N. In Figure 7 the steadying
lines are connected with P, and 0 is merely the connection between the hook and
the shackle M.
Figure 8 shows a hand worked hook suitable for boats hung by two points of
support only; a is a bolt passing through the keel, and the hook forms the head of
the bolt. The letters of reference and the action of the mousing tumbler are as
before explained.
Figure 9 shews another hand worked hook arranged in such manner as to
drop through the thwart when not in use, so as to leave the thwart free from
obstruction. In this Drawing the lower portion is shown in section. In the
thwart is a slot lengthwise of the thwart, and therefore athwart the boat, wide
enough for the hook to pass through when turned athwart the boat, and therefore
not in the position shewn in the Drawing. The lower part of the hook is drawn
out in the form of a bolt d, ending in an enlarged head e, d, passes loosely through
a cross piece f, f, which travels freely upon the two bolts g, 9, which pass through
holes in f, fig', g', have heads to prevent them from passing through the thwart,
and their upper parts are enlarged to prevent f, f, from rising beyond a certain
point; g, g, are also screwed into the cross piece h, h. The keel boat j (which may
have a head at its lower end, so as not to require rivetting below the keel) is
introduced from below, and also screws into h, h; k, k, k, are lock nuts. Any other
arrangement by which the keel bolt shall be crutched or forked in its upper part
for a sufficient depth to allow the hook to drop down below the thwart will
answer the same purpose. When it is desired to lower the hook through the
thwart, it must be twisted through a quarter circle (d revolves easily in f). It
then drops down until stopped by e coming in contact with the head of j; f, f, of
course goes down with it. To prevent the hook from turning accidentally, and so
falling through the thwart when not desired to, each end of the slot in the thwart
is to be closed by a small hinged flap or shutter, which when down comes in
contact with the hook at above the part marked 1, and prevents it from turning.
Such flaps or shutters will also give steadiness to the hook in the athwartship
direction.
This method of stowing the hook below the thwart may also be applied to the
apparatus shown in Figure 5, by furnishing it with a prolongation at the lower
end corresponding with in Figure 9.
Figures 10, 11, and 12 shew three hand worked hooks adapted for attachment
to the stem and stern post of a boat suspended by its extreme ends; m, m, are
bolts intended to pass through the stem or stern post, and to be rivetted on the
outside. Figure 12 shows a strong form for heavy hoats; Figures 10 and 11 are
adapted respectively for cases where it is desired to make the attachment low
down or high up the stem or stern posts relatively to the hook.

page_text: "
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Mark Heaton Robinson in the Great Seal Patent Office on the
16th February 1882.
MARK HEATON ROBINSON, of Hampton Wick, in the County of Middlesex.
IMPROVEMENTS IN BOAT DISENGAGING GEAR."
This Invention relates mainly to improvements on a certain boat-disengaging
gear invented by me, and now in use in Her Majesty's navy and elsewhere.
The gear as at present fitted is applicable only to boats suspended by chain
slings or spaus," such as are generally used in the quarter-boats of Her Majesty's
ships, each sling or pan consisting of a chain hooked or shackled at one end to a
point in the keel of the boat, and at the other to a point near the upper part of the
stem or stern-post, as the case may be. The frame of the apparatus us_hitherto
made (corresponding, though not exactly, with the parts marked K in the Drawings
herewith, especially in Figure 2), is connected by a shackle at its lower end with
that part of the chain sling which leads downwards to the keel, and by a shackle at
its upper end to that part which leads, more or less horizontally, to the stem or
stern-post. In fact the frame of the apparatus serves as one of the links in the
chain. A ring attached to the lower block of the lowering tackle engages with a
tumbling hook, which turns upon a pivot in the frame. This pivot serves also to
connect the upper shackle before mentioned with the upper part of the frame.
The said pivot is also made with an eye at each end, and to these eyes are
attached the steadying-lines connecting the apparatus with the gunwales of the
boat. (The general arrangement of the pivot and the parts connected with it in the
apparatus, as hitherto made, is shown with sufficient accuracy in Figure 3;
O representing the pivot with an eye at each end; K, K, the two plates con-
stituting the frame; M, M, the end view of the upper shackle; and Q, the front
view of the hook.) The tumbling hook as hitherto made has a shank which points
approximately downwards. Below this in the same frame is pivoted a lever, the
short or upper end of which presses against the lower end of the shank of the
hook, so long as the lower or long end of the lever is held by the pull of a
retaining chain. The retaining chains from the apparatus at the two ends of
the boat are connected by a pair of blocks and a line forming a purchase. When
the fall of the purchase is hauled taut and belayed or held, the short or upper
ends of the levers are pressed (by the pull of the retaining chains upon their
lower ends) against the shanks of the hooks, and the hooks are unable to turn
or tumble." But when the fall of the purchase is slacked, the levers permit the
shanks of the hooks to escape, and the hooks " tumble " at the same moment
and release the rings of the lowering tackles simultaneously. The general arrange-
ment of the slings and of the retaining chains and purchase (but not the particular
form or construction of the releasing apparatus), is shown in the after and central
parts of the boat delineated in Figure 1. The apparatus as hitherto used is also
fitted with an appliance for mousing the hook against accidental unhooking,
consisting of two plates, one on each side outside the frame containing the hook.
These plates are rigidly connected with each other, first, by a rivet, and secondly,
by a bolt which passes through the frame, and which serves as a pivot upon which
the mousing plates are able to turn through about the half of a circle, according as
it is desired to place them either in or out of action. As the mousing plates stand
necessarily some distance apart (about five or six centimetres), 'the point or tongue
of the hook is flattened out spoon-shape, that it may the better fill up the space
between them, and render it impossible for the ring to escape from the hook
accidentally while the plates are in the position intended to prevent it. In fitting
""

page_text: the apparatus (as hitherto made) in a boat, it is very desirable so to proportion
the stings that the pivot upon which the hook revolves shall be below the level of
the gunwales, so that the steadying-lines" shall support the apparatus, and the
chain sling with it when the weight of the boat is not borne by the hooks. In
order that the lever of the apparatus may have room to work when thus sunk
below the level of the gunwales, it is necessary in boats where the thwarts and
other fittings are not at a considerable distance below the gunwales, to make special
arrangements to obtain room for the levers by cutting away parts of the thwarts,
or platforms if there be any, or if there be air-cases, by sinking hollow castings
into them into which the lever, &c., may descend.
My present improvements have for their object to render gear of this nature
more compact, so that less depth may be occupied, and so that it may be fitted
to any boat at present hung by slings, without reference to the position of the
thwarts (this improvement is shown in Figure 2). Also the arranging of such gear
so that the moving parts of the slipping or releasing action shall lie entirely above
instead of below the point to which the steadying lines are attached, so that it shall
be applicable even in cases where such fittings as air-cases, gratings, &c., rise almost
to the level of the gunwales (this is shown in Figure 4). Also the arranging of
such gear so that it shall be applicable to boats hung only by two points of
support, and not by slings or spaus (this is shown in Figure 5). Also the provision of
a better mousing" than that heretofore employed to prevent accidental unhooking
which shall be smaller, lighter, and better protected from injury (see Figures 2, 3,
4, and 5, and further applications of it in Figures 6, 7, 8, 9, 10, 11, and 12). Also
the provision of a simpler and cheaper disengaging hook to be disengaged by hand
only for use in boats, to which it is for any reason considered unnecessary to fit the
more expensive simultaneous releasing gear above referred to. Such hand-worked
hooks share with my other described apparatus the advantages, first, that they are
at all times self-supported in a convenient position for looking-on or unhooking,
so that the man charged with that duty does not require to hold up or support
the hook with one hand while hooking on or unhooking the lowering tackle
with the other, but has both hands free for the management of the tackle, and,
secondly, of being efficiently "moused" against the danger of accidental unhooking.
It will be observed that such hand-worked hooks are adapted both for attachment
to slings and to single points of support.
The following is a description of my improved apparatus:—
In Figure 1 (for the sake of variety of illustration) a boat is shown suspended
at the after end by the improved apparatus shown in detail in Figures 2 and 3,
and at the fore end by that shown in Figure 5.
the "
A, B, are chains, taking the place, with the apparatus connected with them of
span sling" generally used in the English navy. C is a fixed bolt rivetted
on the under side of keel, and passing up through a thwart D; its head, which
stands above the thwart, is connected with the corresponding releasing apparatus
in the manner shown in Figure 5, and more fully explained hereafter. H, H, are
rings (preferably the iron straps of the blocks extended downwards to form rings)
attached to the lower blocks of the lowering tackles, which latter may be of any
description commonly used. H, H (which stand athwart the boat, and are therefore
seen edgeways in all the Drawings except Figure 3) engage with the hooks of the
apparatus, and the action of the latter is to release them simultaneously at any
desired moment. To each apparatus is connected (either by hooks or shackles at
or near J, J,) the chain or wire rope E, E, which is divided in the middle by the
purchase F, F. So long as the chains E, E, are stretched taut by the purchase the
hooks of the apparatus are kept in the position shown in the Drawings, but
immediately upon the fall G of the purchase being let go by the person in charge
of the boat the slacking of the chains E, E, permits the hooks to revolve (or
tumble) in the manner presently explained in the description of Figure 2, and
both rings are released simultaneously, thus disengaging the boat from the ship.
The apparatus, as shown in Figures 2 and 3, which is the kind most generally

page_text: suited for boats hung by "span slings" consists of two plates K, K, held at about
three centimetres apart by shouldered rivets L, L, L, L, which rivets form also
stops to check the motion of some of the working parts. The upper end is con-
nected by the shackle M (which works upon the pin O) with the chain A, which
leads to the stem or stern-post, as the case may be. The lower end is similarly
connected by the shackle N working upon the pin P, with the chain B leading to
the keel. The pin O, as shown in Figure 3, has an eye at each end. The steadying
lines are attached to these eyes, and serve to suspend the apparatus in a proper
position for slipping if at any time the boat becomes water-borne before it is
released from the ship. The slings are if possible so proportioned that even when
the boat is suspended by the apparatus the eyes of the pin Ŏ should be below the
level of the gunwales to which the other ends of the steadying lines are attached."
The pin forms also a pivot, upon which works between the two plates K, K,
the curved bar Q, which is able when released to rotate through about half a circle
so as to turn itself upside down and completely free the ring H. As shown in
Figure 2, it is prevented from rotating by the catch R, which latter is held to its
work by the wire rope (or chain may be used) T, T. A few inches from the
apparatus T is spliced or otherwise connected to a small ring to which the chains
or ropes E, E, (see Figure 1) are attached. When E is slacked T is slacked also,
Ris permitted to travel until the projection at its large end clears the corre-
sponding end of Q, and Q being caused to rotate by the pull of the ring H allows
the ring to slip off the point as it rises and to go free; the apparatus then remains
suspended by the steadying lines ready for hooking on again. Qand R are So
proportioned as not to clear cach other until the chain E has been slacked to the
extent of 10 or 12 centimetres; up to that point Q can be brought back into its
place by again hauling upon the chain. S is the pin on which R works. V is a
hole in each of the two plates K, K, through which a pin called a safety pin can
be passed when it is desired to prevent the catch R from moving, and from
releasing Quotwithstanding that the rope or chain T is left slack. The safety pin
is secured to any couvenient part of the apparatus (preferably to an eye at one end
of the pin Z) by a small chain to prevent it from being lost. W is a roller for the
rope or chain T to pass over; X, another roller for the same purpose. Y is a
small tumbler which when in the position shown mouses the hook formed by the
point of the bar Q and the front of the plates K, K; the ring I cannot then
become unhooked accidentally; at the same time Y does not interfere with the
releasing action of the apparatus as above described. If it is desired to clear the
opening of the hook for the purpose either of hooking on or of unhooking by hand,
the tumbler Y can be thrown back towards the catch 1 so as to be out of the
way and to leave the hook unmoused. Y remains in either position by its own
weight resting upon one or the other of the two neighbouring rivets L, L, as the
case may be. When thrown out of action it is accessible through the large holes
shown in the plates K, K, and can be readily pushed by the finger from one
position to the other, its outer edges being notched to facilitate this, and the
pivot Z being a very loose fit to it.
In Figure 3 the ring H is shown by dotted lines only.
In Figure 4 is shown another apparatus also adapted for span slings suitable in
cases where it is desired to keep the steadying lines lower relatively to the working
parts of the apparatus, or where for any reason it is inconvenient to have the
catch R working below the level of the chain which leads to the stem or stern-
post. In this apparatus the working parts concerned in the releasing action are
exactly the same as in Figure 2, and bear the same letters of reference, but the
plates K, K, differ so as to admit of the shackle connecting the apparatus with the
chain A (leading to the stem or stern-post) being attached at the lower rear corner
of the apparatus instead of to the pin O at the top. The pin P is furnished with
an eye at each end to receive the steadying lines instead of the pin O, so that the
working parts of the apparatus now lie entirely above the steadying lines. The
arrangements for mousing and clearing the hook are exactly as in Figure ?.

page_text: The pin can be made the point of attachment for the steadying lines if for
any reason it is desired to keep the slipping action lower than in Figure 4, but not
so low as in Figure 2.
Another apparatus is shown in Figure 5." This is for attachment to a single
fixed bolt rivetted through the keel; here the slipping and mousing arrangements
are exactly as in Figures 2 and 4, and the same letters of reference apply, but the
plates K, K, differ, and the attachment to the boat instead of being by shackles and
chains is as follows:- is a round bolt which passes through the keel and is
rivetted below it as usual. It passes up through and is steadied by any convenient
thwart, air-case, or other similar fitting in the boat, and it ends in a
head b,
immediately above such thwart, &c. The horizontul section of 6 is square or oblong,
fitting loosely in between the lower ends of the side plates K, K, of the apparatus.
Across the top of the head (athwart the boat) is a deep groove to receive the
lowest rivet L of the apparatus. Ate is a hole through the head b, and also
through the plates K, K; a pin is passed through this hole e, and connects together
the apparatus and the head of the bolt. As the head of the bolt enters between
and fits loosely to the plates forming the sides of the apparatus, the apparatus
cannot fall either way laterally, neither can it fall either way in a fore-and-aft
direction, as it is held upright by the rivet Li coming in contact with the sides of
the grooves in which it lies. The apparatus is therefore always in an upright
position and ready for hooking on, or for unhooking by hand, if need be, without
requiring to be held up. The pin which passes through e may be of any convenient
pattern, either a screw pin passing freely through and through one of the plates
K, but threaded to screw into the other plate K, or such a pin as will pass freely
through all three holes if turned into a certain position but secured against
accidental withdrawal when in its place by a projection upon one of the plates K,
which enters first a longitudinal and then a circumferential groove in the pin, with
an action somewhat similar to what is known as a bayonet joint. The pin should
be attached by a chain to the thwart, or to any other convenient point to
avoid loss.
Instead of the bolt a having a head b standing up above the thwart, as in
Figure 5, the upper side of such head may stop flush with the upper side of the
thwart, and the groove in which L lies (in Figure 5) may be omitted. Upon each
side of the bolt head there may be a slot or opening cut through the thwart (each
slot lying in a fore-and-aft direction) through which the two lower ends or tails of.
the plates K. K. may be dropped, such ends or tails being made longer than in
Figure 5. The hole through the head of the bolt and through the tails of K, K,
will then come below the thwart instead of above it, connection being still made
by a pin. as above described. The apparatus will be sufficiently steadied by contact
between the thwart and the plates K, K, at the places where they pass through it.
In cases where it is unnecessary ever to remove apparatus from the boat it may
be permanently secured to the head of the bolt 1.
In cases where it is desired that the apparatus (moaning thereby the frame
K, K, with the curved bar Q, the catch R, the mousing tumbler Y. &c.) shall not
be readily detachable, but shall be always in place ready for use though as far as
possible out of the way. a large slot is cut in the thwart or other fitting by which
the apparatus is steadied, and the apparatus is so connected with the bolt passing
through the keel that it is able, when turned in the right direction, to drop down
through the slot in the thwart so as to be out of the way. The mode in which this
is accomplished is clearly shown in Figure 9, in which, however, the hook repre-
sented is not of either of the kinds herein before described, but of the hand
worked class. to be described presently. But the lower part of Figure 9 (and the
description thereof hereafter following) is as applicable to such apparatus as is
shewn in Figure 5 as to such a hook as is shown in Figure 9.
Figures 6, 7, 8, 9, 10, 11, and 12 show other varieties of apparatus, designed for
unhooking by hand only, and not constructed to disengage both ends of the boat
simultaneously by mechanical means. In these the hook is self-sustained and does

page_text: not require to be held up while the process of hooking-on or unhooking is being
performed. A mousing is also provided similar to that shown in Figures 2 to 5.
In Figures 6 and 7 are shown two varieties of such apparatus adapted for use with
span slings, and corresponding in the method of attachment to the slings and
steadying lines with the apparatus shown in Figures 2 and 4. The letters of
reference are the same as in Figures 2 and 4, K, K, K, representing, however, in
one forging both the two frames K, K, of the former Drawings and the bar Q.
The mousing tumbler Y works in a slot in the substance of K, K, K, upon a
pivot Z. It can be readily reached both from the front and back, and can be
moved at discretion either into the position shown in the Drawings and marked Y,
or into that marked (in Figures 6, 7, 8, and 12 only) in dotted lines. In the first
named position it mouses the hook, from which the ring H cannot then be released
by accident, in the other position it leaves the hook unobstructed for either
unhooking or for hooking on. Y lies in either of these positions by its own weight,
resting in either case upon the bottom of the slot. It is made of less breadth than
the slot, and is thickest at the point where the pivot Z passes through it, so that
its other parts shall not come in contact with the sides of the slot. In Figure (6
the steadying lines are to be attached to the double eye-bolt 0, and P has no
other function than to connect the hook with the shackle N. In Figure 7 the
steadying lines are connected with P, and O is merely the connection between the
hook and the shackle M.
Figure 8 shows a hand-worked hook suitable for boats hung by two points of
support only; a is a bolt passing through the keel, and the hook forms the head of
the bolt. The letters of reference, and the action of the mousing tumbler are as
before explained.
Figure 9 shows another hand-worked hook arranged in such manner as to drop
through the thwart when not in use, SO as to leave the thwart free from
obstruction. In this Drawing the lower portion is shown in section. In the
thwart is a slot lengthwise of the thwart wide enough for the hook to pass
through when turned athwart the boat (and therefore not in the position shown in
the Drawing.) The lower part of the hook is drawn out in the form of a bolt d
ending in an enlarged head e; d passes loosely through a crosspiece f, f, which
slides freely upon the two bolts g, g, which pass through holes in it; g, g, have
heads to prevent them from passing downwards through the thwart, and their
upper parts are enlarged to prevent f, f, from rising too far up them; 9, 9, are also
screwed into the crosspiece h, h. The keel-bolt (which may have a head at its
lower end, so as not to require rivetting below the keel) is introduced from below,
and also screws into h. h; k, k, k, are lock-nuts. Any other arrangement by
which the keel-bolt shall be crutched or forked in its upper part for a sufficient
depth to allow the hook to drop down below the thwart will answer the same
purpose. When it is desired to lower the hook through the thwart it must be
turned through a quarter circle (d revolves easily in ). It then drops down until
stopped by e touching the head of j; f, f, of course goes down with it. To prevent
the hook from turning accidentally, and so falling through the thwart when it is
not desired to do so, each end of the slot in the thwart is closed or filled up by a
small hinged flap or lifting shutter, which when down comes in contact with the
hook at about the part marked and prevents it from turning. Such flaps or
shutters will also give steadiness to the hook in the athwartship direction.
This method of stowing the hook below the thwart may also be applied to the
apparatus. .shown in Figure 5 by furnishing it with a prolongation at the lower end
corresponding with d in Figure 9.
Figures 10, 11, and 12, show three hand-worked hooks adapted for attachment
to the stem or stern-post of a boat suspended by its extreme ends; m, m. are bolts
intended to pass through the stem or stern-post and to be rivetted on the outside.
Figure 12 shews a strong form for heavy boats; Figures 10 and 11 are adapted
respectively for cases where it is desired to make the attachment low down or
high up the stem or stern-post relatively to the hook.

page_text: Having thus described the nature of my Invention and the manner of performing
the same, I would have it understood that I claim :-
-
First. The combination of a curved bar and a catch or detent acting substantially
in the manner described with reference to Figures 2, 3, 4, and 5, for slipping or
releasing the boat, whereby the vertical height occupied by the acting parts is
much less than heretofore.
Second. The combination with hooks of the kinds herein before described used
for the suspension or release of a boat (whether they be "tumbling" hooks or
standing ones) of a single tumbling block for mousing the hook, substantially as
shewn in Figures 2 to 12; such mousing block working, in the case of a tumbling
hook, in the space between the sides of the frame carrying the hook (as shown at
Figure 3), and in the case of a standing hook, in a slot in the substance of the
hook.
Third. The combination of boat disengaging gear, substantially as described with
reference to Figures 2 and 3.
Fourth. The combination of boat disengaging gear with all the moving parts of
the slipping gear above the span sling by which the boat is suspended, substantially
as described with reference to Figure 4.
Fifth. The combination of boat disengaging gear, substantially as described with
reference to Figure 5.
Sixth. The hand worked hooks fitted with mousing tumblers, substantially as
described with reference to Figures 6, 7, 8, 9, 10, 11, and 12.
In witness whereof, I, the said Mark Heaton Robinson, have hereunto set
my hand and seal, this Fourteenth day of February, in the year of our
Lord One thousand eight hundred and eighty two.
MARK H. ROBINSON.
1.8.)