An Instrument for Observing the Rolling of a Ship.
Year: 1896

page_text: PROVISIONAL SPECIFICATION.
An Instrument for Observing the Rolling of a Ship.
I, ARNULPH MALLOCK, of No. 3 Victoria Street, in the County of London,
do hereby declare the nature of this invention to be as follows:-
My invention relates to an instrument for use on ship-board to observe the
extent or angle to which the vessel rolls.
I provide a tank in the form of a cylinder or cylindrical segment with transparent
ends, and place this with its axis horizontal. In water or other liquid, with which
the tank is charged, I mount a paddle wheel having its axis coinciding with
that of the tank and supported on bearings arranged to be as frictionless as
possible.
The wheel is so constructed that its weight is equivalent to that of the liquid
displaced by it, and it is made slightly heavier at oue part of its circumference so
that when the tank is at rest the wheel takes a definite or zero position, its heavy
part hanging vertically under its axis. The circumference of the wheel is
graduated and a pointer is fixed to the tank so that the relative rotation of the
tank and wheel can be read by looking through the transparent end.
As the vessel rolls, the tank turns with it about its axis, but as this, according
to a well known property of fluids, gives very little rotary motion to the liquid,
the wheel remains virtually at rest, so that the extent of the angular movement of
the tank, and consequently of the vessel, of which it forms part, is shewn by the
division on the wheel which the pointer indicates.
Dated this 10th day of September 1896.
ABEL & IMRAY,
Agents for the Applicant.
I, ARNULPH MALLOCK, of No. 3 Victoria Street, Westminster, in the County
of London, do hereby declare the nature of this invention, and in what manner
the same is to be performed to be particularly described and ascertained in and
by the following statement :-
My invention relates to an instrument for use on ship-board to observe the
extent or angle to which the vessel rolls.
Figure 1 of the accompanying drawings is a vertical section and Figure 2 is a
front view of the instrument according to my invention.
I provide a tank A in the form of a cylinder or cylindrical segment with
transparent end B and place this with its axis horizontal. In water or other
liquid, with which the tank A is charged, I mount a paddle wheel C having its
axis coinciding with that of the tank and supported on bearings arranged to be as
frictionless as possible.

page_text: The wheel C is so constructed that its weight is equivalent to that of the liquid
displaced by it, and by means of adjustable weights D and E it is made slightly
heavier at one part of its circumference so that when the tank is at rest the wheel
takes a definite or zero position, its heavy part hanging vertically under its axis.
The circumference of the wheel is graduated as at F and a pointer G is fixed to
the tank so that the relative rotation of the tank and wheel can be read by looking
through the transparent end. A chamber H allows for expansion and contraction
of the liquid in the tank.
As the vessel rolls, the tank turns with it about its axis, but as this, according
to a well known property of fluids, gives very little rotary motion to the liquid, the
wheel remains virtually at rest, so that the extent of the angular movement of the
tank, and consequently of the vessel of which it forms part, is shewn by the division
on the wheel which the pointer indicates.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
An instrument for observing the rolling of ships, constructed and operating
substantially as described and illustrated.
Dated this 26th day of n
1007
ABEL & IMRAY,
Agents for the Applicant.