CERTAIN IMPROVEMENTS IN THE CONSTRUCTION AND COMBINATION OF MACHINERY FOR SECUR- ING, SUPPORTING, AND STRIKING. THE TOPMASTS AND TOP-GALLANT-MASTS OF SHIPS AND OTHER VESSELS
Year: 1829

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, J, WILLIAM
PRIOB, late of Albany Road, Camberwell, in the County of Surrey, but now
of Salisbury Place, Walworth, in the same County, Gentleman, send greeting.
WHEREAS His present most Excellent Majesty King George the Fourth,
in and by His Letters Patent under the Great Seal of Great Britain, bearing
date at Westminster, the Eleventh day of April, in the year One thousand
eight hundred and twenty-nine, in the tenth year of His reign, did, for
Himself, His heirs, and successors, give and grant unto me, the said William
Prior, His especial licence that I, the said William Prior, my executors,
administrators, and assigns, or such others as I, the said William Prior, my
executors, administrators, or assigns, should at any time agree with, and no
others, from time to time and at all times during the term of fourteen years
therein expressed, should and lawfully might, make, use, exercise, and vend,
within England, Wales, and the Town of Berwick-upon-Tweed, and also in
all His Majesty's Colonies and Plantations abroad, my Invention of “CERTAIN
IMPROVEMENTS IN THE CONSTRUCTION AND COMBINATION OF MACHINERY FOR SECUR-
ING, SUPPORTING, AND STRIKING. THE TOPMASTS AND TOP-GALLANT-MASTS OF
SHIPS AND OTHER VESSELS;" in which said Letters Patent is contained a pro-
viso, obliging me, the said William Prior, by an instrument in writing under
my hand and seal, particularly to describe and ascertain the nature of my said
Invention, and in what manner the same is to be performed, and to cause the

page_text: same to be inrolled in His Majesty's High Court of Chancery within six
calendar months next and immediately after the date of the said Letters
Patent, and also that I, the said William Prior, my executors, administrators,
or assigns, should supply or to cause to be supplied for His Majesty's service
all such articles of the said Invention as I or they should be required to
supply, in such manner, at such times, and upon such reasonable prices and
terms as should be settled for that purpose by the Commissioners of His
Majesty's Navy for the time being, (as in and by the said Letters Patent will
(inter alia), upon reference being thereunto had, more fully and at large
appear.
NOW KNOW YE, that my improvements in the construction and combina-
tion of machinery for securing, supporting, and striking the topmasts and top-
gallant-masts of ships and other vessels consists in the novel construction of
an apparatus to be employed in the place of the fid usually applied to that
purpose, which apparatus contains either a sliding or a swinging bolt, worked
by a cam or excentric roller. The two kinds of bolts with the rotatory cam are
shewn in the several Figures of the Drawings hereunto. annexed.
Figure 1 represents the parts in operation. a is the topmast, shewn partly
in section, which is supported by the two sliding bolts 6, 6; the bolts slide
in sockets or carriages resting upon the tressels c, c, and their points being
projected forward into recesses in the sides of the mast (as shewn in this Figure),
support it as long as the bolts are prevented from sliding back"; "but when the
bolts are allowed to recede, as in Figure 2, then the mast looses its support
and slides down between the tressels. The particular feature of novelty in this
Invention is the contrivance whereby the bolt is retained in its place, which is
by means of a cam or excentric roller d; part of the roller is made cylindrical
and concentric with its axle, which fits into a segment-formed: recess at the
back part of the bolt, and while the concentric part of the roller bears against
the recess the bolt is prevented from receding, and consequently the mast is
supported, as in Figure 1. On turning the roller d'round by a handspike, as e,
or by a winch to be applied to its axle, or by any other suitable contrivance;
the excentric part of the roller is brought against the recess behind the bolt;
as at Figure 2, and the resistance being thus removed, 'the weight of the mast
bearing upon the points of the bolts, causes them to slide back and allow the
mast to descend as in the act of striking. Figure 3-shews a horizontal repre-
sentation of the crosstrees and tressels, with the topmast a cut across; "in
section, at the aperture where the points of the bolts enter; the bolts ‘6; 6, 'being
projected forward, as in Figure 1. Figure 4 is a similar representation of tlic
crosstrees and tressels, the bolts being withdrawn and the mast sliding down, as

page_text: in Figure 2. In order to guide the bolts with certainty, a groove is cut in the
upper part of each bolt, as shewn by dots in Figures 1 and 2, for the purpose
of receiving a concentric rib carried round the excentric part of the cam; but
I deem this rib and groove of little importance. My other contrivance,
consisting of swinging bolts, is shewn in the Drawings at Figures 5, 6, 7, and 8.
In Figure 5, as in Figure 1, a is the topmast; b, b, the bolts, swinging on
pivots or axles mounted in carriages supported on the tressels c, c. The
excentric rollers d, d, act against segment recesses at the backs of the swinging
bolts b, which confine them and cause their points to support the masts, as in
Figure 5. On turning the cam rollers round by a handspike or other con-
trivance the excentric part of the cam comes against the bolt and thereby
releases it, when the weight of the mast bearing on the points of the bolts,
causes them to descend, and the mast slides down, as in Figure 6. The two
horizontal views, Figures 7 and 8, represent the swinging bolt in the two
positions similar to the sliding bolt in Figures 3 and 4.
Having described the construction of my improved apparatus for securing,
supporting, and striking the topmasts and top-gallant-masts of ships, &c.
I wish it to be understood that the particular feature of this Invention, and
that which I exclusively claim under the above recited Letters Patent, is, the
cam or excentric rollers for holding or releasing the bolt, whether the same be
applied to a sliding or a swinging bolt.
In witness whereof, I, the said William Prior, party hereto, have hereunto
set my hand and seal, this Tenth day of October, in the year of our
Land On there