IMPROVEMENTS IN PROPELLING SHIPS AND OTHER SIMILAR VESSELS
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by Alfred Rickarby at the Office of
the Commissioners of Patents on the 5th July 1882.
"
ALFRED RICKARBY of Newcastle upon Tyne in the County of same name,
Whitesmith. "IMPROVEMENTS IN PROPELLING SHIPS AND OTHER SIMILAR
VESSELS
"
My invention relates to improved means of propelling ships or similar vessels,
which means are applicable also to steering either separately from or in conjunction
with the ordinary rudder.
A tube of circular or other section is constructed or fixed horizontally (or
inclined toward the stern) in the bottom of the ship centrally on top of, or in place
of, "Keelson" with its inner end closed and its mouth opening out at stern of
ship. This tube has working in it a plunger or piston (either an easy working fit
or packed) connected by a rod, or rods, working through a stuffing box or boxes at
inner end direct to piston rod of engine, or indirectly through levers from the
piston rod. At the sides of this central tube I construct two tubes of circular or
any other suitable section, each preferably of half the area of the central tube, and
forming a U, the loop of which joins central tube with their outer ends or mouths
opening out of the after "run" of the ship. The engines being started the plunger
in the central tube in the forward stroke is followed by the water, which on the
backward stroke is driven out at the open mouth of the tube against the
surrounding body of water, propelling the ship forward, water at the same time
rushing through the two side tubes and filling the central tube in front of the
plunger the forward stroke of which expels the water through the side tubes and
continues the propulsion of the ship the effect of the two columns is thus continuous
by their double action. I may in some cases fit these side tubes with pistons or
plungers worked by rods direct or by levers from auxiliary cylinders and making
alternate strokes with the central piston, a column of water being contained
between the forward sides of the central and side plungers which equalises their
effective action. When the action is to be reversed, to stop the ship or propel her
astern. I reverse the action of the columns of water, ejected from the tubes, by
doors or valves fitted with suitable working gear and by means of these doors, or

page_text: valves, the steering of the ship may be effected, either in conjunction with the
rudder or independently of it, in case of accident. The motive power may be derived
from any of the existing types of engines simple or compound. In the latter case
the two side plungers may be worked each from a high pressure cylinder and the
central plunger from the low pressure cylinder, or vice versa. In all cases I prefer
the application of the motive power direct to the plunger or plungers without the
intervention of levers or cranks.
To prevent "racing" when the stern of ship lifts out of the water I propose to
use a governor which will be operated automatically by the movements of the
ship to cut off the steam or "cushion" it in the cylinders, but this forms no part
of my invention.
I do not confine myself to the use of one central and two side tubes as the
respective arrangement of these will depend upon the construction of the ship and
the propelling power required to be developed and utilised.