IMPROVEMENT OF PLATFORMS OF TURRETS ON SHIPS OF WAR
Year: 1872

page_text: PROVISIONAL SPECIFICATION left by James Stapleton at the Office
of the Commissioners of Patents, with his Petition, on the 9th
December 1872.
I, JAMES STAPLETON, of Sidbury, nr. Sidmouth, County of Devon,
do hereby declare the nature of the said Invention for "IMPROVEMENT
OF PLATFORMS OF TURRETS ON SHIPS OF WAR," to be as follows:-
The improvement in platforms for turrets on ships of war for which I
claim the Invention consists of a true hemisphere fixed in the ship's
bold perfectly level; in its centre will rest the platform, an upright
cylinder whose diameter will be equal to that of the turret, the curve of
whose base will coincide with that of the hemisphere in which it is
placed, resting on suitable friction rollers and terminating a little
above or below the level of the hemisphere; on it the platform for
carrying the turret with its rollers will be placed, a pivot fixed in the
platform passing up through the floor of the turret will unite it to the
platform. A belt of iron being a continuation of the cylinder or plat-
form would surround the base of the turret for a certain height, leaving
a few inches of space between them. Friction rollers could be
introduced to insure its steadiness without interfering with the turret's

page_text: revolving freely. The turret will revolve in a collar placed as high up
as possible, forming an universal joint secured to the deck of the ship
under the protection of the armour plating and confining the turret at
this point, but not interfering with its revolving, permitting it to remain
upright. The turret and the platform now completely united stands in
the centre of the hemisphere, the action would be as follows:―The
hemisphere which represents an universal incline being part of the ship
partakes of its motion, and on the ship's rolling presents an inclined plane
to the base of the platform down which it gravitates. The return roll of
the ship presents a contrary incline down which it likewise glides, and
thus on alternately, in the mean time the pitching also presents its
It is thus
incline of the hemisphere to be acted upon in like manner.
shewn that the hemisphere acting as a universal incline in conjunction
with the law of gravitation, will always preserve the platform and turret in
an upright position, notwithstanding the rolling and pitching of the ship,
by its self-acting and ceaseless oscillations until the ship is at rest, thus
affording a solid basis for the platform and turret allways presenting a
horisontal surface. The great wear and tear that would arise from this
constant motion can be prevented by stays from the circumference of the
hemisphere placed at equal distances around, screwed home against the
platform, rendering it motionless; this will not affect the mechanical
action of the turret in any way, it will only suffer from the rolling and
pitching of the ship, just as it does at present. The hollow cylinder or
platform should be filled with concrete to a certain extent to give it a
command over the turret it carries.
Another kind of platform might be adopted by placing a hemisphere
somewhat less in diameter within the one fixed in the ship, friction
rollers being introduced between them and weighted at the bottom, so
as to bring the centre of gravity as low as possible; upon this the turret
could be placed. The law of gravitation would act upon this form of
platform in the same way as I have already described.
The distance from the collar to the base of the platform would be the
length of the radius that would determine. the curve of the hemisphere.