IMPROVEMENTS IN TACKLE BLOCKS
Year: 1856

page_text: LETTERS PATENT to Montague Richard Leverson, Solicitor, of 12,
St. Helen's Place, London, for the Invention of "IMPROVEMENTS IN
TACKLE BLOCKS."-A communication.
PROVISIONAL SPECIFICATION left by the said Montague Richard Lever-
son at the Office of the Commissioners of Patents, with his Petition, on
the 3rd June 1856.
I, MONTAGUE RICHARD LEVERSON, Solicitor, of 12, St. Helen's Place,
London, do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN TACKLE BLOCKS," to be as follows:-.
The calamities that have so frequently occurred for want of some better
means of lowering ships' boats, not only in cases of emergency, but at all times,
have directed attention for some time past to the necessity for providing some
simple apparatus by which they may be readily disengaged from the tackles.
Ilitherto it has generally been necessary to lower a couple of men to unlook
the blocks from the ring bolts by which the boat was suspended, and with a
rough sea it has been attended with difficulty and danger. The object of -my
Invention is to provide a means by which the unhooking operation may be
automatically performed, and for that purpose the hooks of the lower blocks
of each set of tackles are hung upon pivots, and provided with counterbalance
weights or springs, by which they are detached from the rings at the moment
the weight of the boat is supported by the water. When there is no strain
upon the book, the preponderance of the counterbalance turns it over with the
point of the hook downwards, and effectually disengages it from any weight to
which it might previously bave been attached.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Montague Richard Leverson in the Great Seal Patent Office
on the 11th October 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, MONTAGUE
RICHARD LEVERSON, of No. 12, St. Helen's Place, in the City of London, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Пer Letters
Patent, bearing date the Third day of June, in the year of our Lord One
thousand eight hundred and fifty-six, in the nineteenth year of Iler reign, did,
for Herself, Her heirs and successors, give and grant unto me, the said Mon-
tague Richard Leverson, Her special license that I, the said Montague
Richard Leverson, my executors, administrators, and assigns, or such other
as I, the said Montague Richard Leverson, 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, and exercise and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and the Isle of Man, an Invention
for IMPROVEMENTS IN TACKLE BLOCKs, upon the condition (amongst others)
that I, the said Montague Richard Leverson, by an instrument in writing
under my hand and seal, 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 Montague Richard Leverson, 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 (that is to say):-
-
The calamities that have so frequently occurred in lowering ships' boats
have long directed attention to the necessity for providing a simple apparatus
by which they may be readily disengaged from the tackles. Hitherto it has
generally been necessary to lower a couple of men to unhook the blocks from
the ring bolts by which the bolt was suspended, and in a rough sea it has been
an operation attended with difficulty and danger. The object of my Invention
is to provide a means by which the disengagement may be automatically
performed, and for that purpose the hooks of the lower blocks of cach set of
tackles are hung upon pivots placed slightly aside from the centre line of the
blocks, and are provided with counterbalance weights, by which they are

page_text: detached from the rings at the moment the weight of the boat is supported by
the water. When there is no strain upon the hook the preponderance of the
counterbalance turns it over with the point of the hook downwards, and
effectually disengages it from any weight which might previously have been
attached. To avoid the inconvenient length consequent upon placing the hook
sufficiently far below the body of the block to admit of a counterbalance large
enough and with leverage enough to ensure the disengagement of the hook
under disadvantageous circumstances, the block is made with a recess between
the sheaves to admit the counterbalance, and the sides of the recess are pro-
vided with metal cheeks, that the strength may be retained.
Figure 1 in the accompanying Drawing represents in section the lower block
of a set of tackles with the book in the position which it occupies when a
weight is suspended from it; Figure 2 is a side clevation of the same; Figure 3
is an elevation, similar to Figure 1, with the hook reversed. The same letters
in the different Figures indicate similar parts.
A is the hook from which the boat or other weight is suspended; b, the
counterbalance weight, made sufficiently heavy to turn the hook over; c, the
pivot or centre on which the hook turns, placed slightly aside from the centre
line of the block to increase the leverage of the counterbalance on the hook;
d, d, lugs formed with the strap, carrying the pivot or centre for the hook;
e, e, metal plates forming the sides of the recess into which the counterbalance
fits; ff, rivets securing the plates and other parts of the shell together;
9, pin by which the counterbalance and hook may be retained in position
when desired.
Having thus fully described my Invention, and illustrated it by the Sheet of
Drawings hereunto annexed, I wish it to be understood that I do not confine
myself to the details described, as they may be varied without departing from
the nature of my Invention; but what I claim in the construction of the tackle
block is, the combination of a counterbalance weight fitting into a recess of the
block with the hook and the pivot on which it turns, substantially, as described,
so that an attached weight may be automatically disengaged.
In witness whereof, I, the said Montague Richard Leverson, have here-
tofore set my hand and seal, this Eleventh day of October, in the year
of our Lord One thousand eight hundred and fifty-six.
MONTAGUE RD LEVERSON. L.S.)