IMPROVEMENTS IN PRO- PELLING VESSELS AND IN APPARATUS EMPLOYED THEREIN
Year: 1867

page_text: 1.
PROVISIONAL SPECIFICATION left, by, Clinton Edgcumbe Brooman at
the Office of the Commissioners of Patents, with his.. Petition, on the
27th March 1867.-A communication from abroad by Richard Dover
Chatterton, of Cobourg, Canada West.
I, CLINTON EDGCUMBE BROOMAN, of the Firm of Robertson, Brooman, and
Company, of 166, Fleet Street, in the City of London, Patent Agents; do
hereby declare the nature of the said. Invention..for "IMPROVEMENTS IN PRO-
PELLING VESSELS AND IN APPARATUS EMPLOYED THEREIN," to be as follows:-
This Invention consists in propelling ships and other vessels in the manner
and by apparatus constructed and, acting, as hereafter described.. A pipe or
pipes being laid longitudinally through the vessel below the water line a steam
pump is employed in connection with, each to admit the water forward, and
discharge it aft; valves are arranged to restrain the flow of water to the desired
direction. Forward and abaft of each pump are two sets of valves opening in
different directions, one or the other being brought into use according to the
desired direction of motion forward or astern. The reversal is performed by
simultaneous shifting of the valves, the motion of the pump being continuous,
and the water being discharged, in the wake of the vessel. Each pipe is thus
provided with four valved diaphragms, the valves of two opening forward.and
those of. the other two aft. The reversal of the direction of, motion neces-
sitates the simultaneous motion of all. The respective valves of a given pair
are connected by, racks and pinions so as to move in contrary directions, and
the respective pairs are connected by racks and spur wheel so as to make.the
operation of reversal simultancous forward and abaft the pump. As before

page_text: stated pipes are laid longitudinally of the vessel below the water line, and as
they are counterparts I shall describe one only, merely stating that, first, they
may discharge alternately so as to make the discharge practically continuous;
secondly, they may be worked in contrary directions so as to turn the vessel;
thirdly, one or more may be used at discretion. Communicating with the
interior of the pipe is a pump chamber, in which reciprocates a plunger
worked by a steam engine, which having no particular points of novelty I do
not desire otherwise to describe than that it has a direct action. One dia-
phragm in front of the pump is down and has self-acting valves, which open
towards the rear and admit water to flow aft through the forward portion of
the pipe so as to supply the pump chamber on the upward stroke of the
plunger, the water in the rear portion of the pipe being prevented from coming
forward as the valves in the rear of the diaphragm which is down do not
open in that direction, so that the water only comes in from the front as the
plunger rises. When the plunger descends the valves in the front diaphragm
are closed against its passage forward, and the valves in the rear diaphragm
open and admit its passage aft. As the pressure in the pipe meets with the
resistance of the front diaphragm the vessel is urged forward, the water escaping
aft to the extent of the displacement of the plunger, on the familiar principle
known as reaction, and demonstrated in the turbine wheel and other mechanical
devices.
...The operation in, brief. may be described as follows:-In the downward
stroke of the piston the self-acting valves in the front diaphragm close, the
pressure against them within being then greater than from without, and the
ship with its pipe and column of water therein is urged forwards with a force
proportionate to the said pressure, this pressure being simultaneously and
equally exerted againt the column of water in the pipe abaft the rear dia-
phragm, which was previously travelling with and at the same rate of speed
as the ship. The upstroke of the piston is effected by pressure of water from
the bow (through the forward portion of the pipe) opening the valves to admit
the requisite fresh supply for the pump cylinder, and no adverse current is
created, as the direction of the water is from the bow aft, or at least from that
end of the vessel which is in the advance at the particular time. Again, the
cumulative force of the descending piston is exerted upon the column of water
in the rear portion for the time being of the pipe (which in the character of
an eddy is being continually forced along by the action of the surrounding sea
with a momentum in the direction of and equal to that of the ship), and not
as with the paddle or screw expended upon the outside water, which relatively
to the ship is passing aft constantly. The front diaphragm, before referred to,

page_text: is connected by a rack and pinion with the rack of another valved diaphragm
also in front of the pump, so that as the former is raised the latter is lowered.
The same is true of the rear valved diaphragm, before referred to, and another
rear diaphragm, and these duplicate sets are moved by the rotation of a shaft
which rotates a wheel and elevates and depresses respectively the racks
according to the direction in which it is turned. When the second pair of
valved diaphragms is lowered the first pair is raised, and the water flows in
the other direction as the plunger reciprocates in its chamber, having the
effect of driving the vessel astern, the reversal being made by a simple motion
of the crank of the wheel just referred to by the officer on deck. The reversal
may be effected either by elevating rods attached to the diaphragm and moved
by cog wheels, by chains and pulleys, or otherwise. During the down stroke
of the piston the ship with the body of water contained in the forward portion
of the pipe is (when under way) pressed through or against the sea by the
combined power of her engine and the momentum she has at the time
attained, the front valves being then closed and those aft the pump cylinder
open; at the same time the column of water in the rear portion of the pipe is
also being urged forward by the pressure of the sea behind at a rate of speed
equal to that of the ship less only the check produced by the power of the
descending piston, its momentum being entirely distinct from and independent
of that of the ship and column of water in front, inasmuch as it is capable'
of being pressed against and stopped without at all impeding them other than
by friction of the pipe slipping over it as they leave it behind. In the up
stroke, the pressure in front being relieved, the water from the bow flows
rapidly inwards and upwards against the ascending piston, the front valves
opening to admit it, while those in rear being closed by the then superior
pressure from the stern the ship is still pushed forward, and the column of
water aft the valves recovers its full momentum ready for renewed resistance
to the piston, thus supplying an ever-increasing strength of propelling fulcrum
proportionate to the speed of the vessel, whereas with any form of propeller
acting on the outside sea direct it must of necessity be constantly diminishing
the faster she runs away from it.