IMPROVEMENTS IN MASTHEAD AND OTHER HOISTING BLOCKS."
Year: 1870

page_text: LETTERS PATENT to William Angus, of Fraserburgh, in the County
of Aberdeen, for the Invention of "IMPROVEMENTS IN MASTHEAD AND
OTHER HOISTING BLOCKS."
PROVISIONAL SPECIFICATION left by the said William Angus at the
Office of the Commissioners of Patents, with his Petition, on the
13th April 1870.
I, WILLIAM ANGUS, of Fraserburgh, in the County of Aberdeen,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
MASTHEAD AND OTHER HOISTING BLOCKS," to be as follows:-
My improvements refer to masthead and other hoisting blocks, and
are as follows:-The pin or bolt of the block has a ratchet wheel fixed
to it and is itself a fixture in the masthead (supposing it to be applied
to such a purpose as that). The sheave to the rim of which the covers
which enclose the interior or ratchet part are fitted is loose and carries

page_text: on the inside a pawl or pawls which take into the ratchet, and it also
carries a spring or springs for the pawl or pawls. By this means the
sheave is retained in any desired position.
SPECIFICATION filed in pursuance of the conditions of the Letters
Patent, and of an Order of the Lord Chancellor, by the said William
Angus in the Great Seal Patent Office on the 26th October 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ANGUS, of Fraserburgh, in the County of Aberdeen, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirteenth day of April, in the year
of our Lord One thousand eight hundred and seventy, in the thirty.
fourth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said William Angus, Her special licence
that I, the said William Angus, my executors, administrators, and assigns,
or such others as I, the said William Angus, my executors, adminis-
trators, 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 "IMPROVEMENTS IN MASTHEAD
AND OTHER HOISTING BLOCKS," upon the condition (amongst others) that I,
the said William Angus, my executors or administrators, by an
instrument 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 William Angus, 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, reference being had to the accompanying Drawings,
and to the letters of reference marked thereon, that is to say :-
My improvements refer to masthead and other hoisting blocks, and
are as follows:-The pin or bolt of the block has a ratchet wheel fixed

page_text: to it, and is itself a fixture in the masthead (supposing it to be applied
to such a purpose as that). The sheave to the rim of which the cover
which encloses the interior or ratchet part are fitted is loose and carries
on the inside a paul or pauls which take into the ratchet, and it also
carries a spring or springs for the paul or pauls. By this means the
slicave is retained in any desired position.
And in order that my Invention may be more clearly understood I
have illustrated the same by the accompanying Drawings, of which
Figure 1 is an outside plan view of the ratchet pulley shewing the
cover fastened by four screws. Fig. 2 is also a plan of the ratchet
pulley but with the cover removed. The pin or bolt a which is fixed
in the masthead has a ratchet wheel 6 fixed to it. Two pawls c, c, fall
into the teeth of the same on opposite sides as shewn at Fig. 2. The
pawls have cach a spring d which keeps the pawl up to the work. The
pawls turn on pins or screws fixed in lugs on the body of the pulley,
which has also four lugs for the screws that hold the cover on.
Fig. 4 shows the masthead block with its strap complete and as
suitable for boats' masts, ships' yards and for catheads for weighing
anchor.
Fig. 5 shews the Invention applied to a common hoisting block. It
is fitted with a clutch lever 7 which turns upon a fulcrum pin and has
a projecting stop which falls into one of four notches on a boss fixed
to the centre pin or bolt. This arrangement is for the purpose of
slacking off. A spring keeps the lever up to the work, and stops m, m,
are provided to limit the sweep or travel of the same.
As will be evident to any one conversant with such mechanical details
the same may be varied without departing from the nature of this my
Invention, but what I claim as my Invention is, the construction of
ratchet pulleys substantially as described and shewn, and their
application to mastheads and for other hoisting purposes.
In witness whereof, I, the said William Angus, have hereunto set
my hand and seal, this Twelfth day of October, in the year of
our Lord One thousand eight hundred and seventy.
WILLIAM ANGUS. (L.S.)