IMPROVEMENTS IN THE CON- STRUCTION OF FLOATING BODIES, AND IN THE MEANS OF SUPPORTING FLOATING STRUCTURES
Year: 1858

page_text: application for Letters Patent was not given within the time prescribed
by the Act.)
PROVISIONAL SPECIFICATION left by Joseph John Murphy at the
Office of the Commissioners of Patents, with his Petition, on the 9th
August 1858.
I, JOSEPH JOHN MURPHY, of Belfast, Spinner and Weaver, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN THE CON-
STRUCTION OF FLOATING BODIES, AND IN THE MEANS OF SUPPORTING FLOATING
STRUCTURES," to be as follows:-
The object of this Invention is to enable a floating structure, or a structure
erected on a floating foundation, to maintain a vertical or nearly vertical
position when placed in a tide way or surf, or where otherwise subject to the
action of the waves, and therefore be fitted for the erection of floating batteries,
lighthouses, beacons, and other constructions or works. It consists of one or
more inverted air-tight vessels somewhat like a gasholder, of such a height or
depth as shall allow of a permanent air space being maintained, and by which
the action of the waves, or the alterations of the level of the water externally,
shall be permitted freely to communicate and operate within the said inverted
vessel, and thus counteract the rolling and oscillating motion, or tendency.
to motion, which otherwise exists in bodies immersed in or floating freely.
in a sea way. The diameter of the floating vessel must be in proportion
to its vertical height, as also to the purpose for which it is designed to be
employed.

page_text: I prefer, for several of the purposes for which this Invention is designed or
intended to be used, to construct the vessel in iron, or any other suitable
metal, and of a shape circular on the plan.
I propose to form one or more water-tight chambers, which may be used as
cabins, or for other purposes, in the upper part of the vessel, by inserting a
horizontal division plate at a suitable distance from the top or deck of the
floating structure, but in some small structures this may not be necessary.
Thus the flotative power would be regulated by the capacity of the inverted
vessel, and the height to which it might be maintained in the water would be
governed by the quantity of air contained between the upper side of the
inverted vessel and the surface of the water within it. And in the event of
the inverted vessel becoming by any accident full of water, the buoyancy of
the entire structure will still be maintained by the flotation of the water-tight
chambers in the upper part.
I introduce a suitable arrangement of stays, struts, and braces, to prevent
collapse or distortion or straining, either from internal or external pressure or
injury arising from other causes. I propose to ballast and otherwise trim or
regulate the centre of gravity, &c., of the vessel, either by loading the bottom,
inner edge, or flanch of the inverted open mouthed vessel, or by any of the
well known methods, and farther secure a requisite degree of stability. I also
so connect the inverted vessel with an air-pump, that I can re-charge the
same when necessary, and by means of cocks suitably disposed, can, to an
extent, regulate the degree of immersion or height of flotation.