IMPROVEMENTS RELATING TO THE APPLICATION OF HYDRAULIC POWER FOR DREDGING PURPOSES, AND IN MACHINERY THEREPOR
Year: 1875

page_text: PROVISIONAL SPECIFICATION left by William Robert Lake at the
Office of the Commissioners of Patents, with his Petition, on the
30th October 1875.-A communication from abroad by William
Henry Newton, of Chicago, Illinois, United States of America.
I, WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co.,
Patent Agents, Southampton Buildings, London, do hereby declare the
nature of the said Invention for "IMPROVEMENTS RELATING TO THE APPLICATION
OF HYDRAULIC POWER FOR DREDGING PURPOSES, AND IN MACHINERY THEREPOR," &
communication, to be as follows:-
The principle involved in this Invention is the combined action of two
or more hydraulic currents to excavate and dredge simultaneously,
excavating by jets of water discharged under high pressure through
suitable nozzles against and underneath the face of the material or
deposit to be removed. The jet is used exclusively to excavate and float
the material, undermining it by excavating, and disintegrating the mass
through the impact and force of the discharging jet directly with the
deposit floating, and temporarily suspending the excavated material in
the surrounding volume of water by the reaction of the currents pro-

page_text: duced by the discharging jets, simultaneously sucking into the mouth of
a suction or vacuum pump pipe the whole volume of suspended material,
elevating it within the action of the force pump to give the whole
volume the required velocity to discharge it through pipes at any desired
height or distance. By giving the jet a rotary motion around its own
axis increased efficiency is obtained.
A transverse and longitudinal movement is imparted to the traversing
dredge on the surface of still water, or to the submerged dredge on the
bottom in places where violent or rapid oscillations of the surface prevent
the operation of the traversing dredge.
The mouth-piece of the suction pipe for the surface traversing dredge
is made reversible, combining with its action a reversible discharging jet,
thereby securing uniform action of the excavating jets in advance of the
mouth of the suction pipe. The velocity of the excavating jets discharge
will depend upon the character of the material to be excavated, and is
entirely practical up to two hundred and fifty feet per second. The
minimum velocity of the volume through the suction pump is about
thirty-two feet per second. By using the vacuum pump masses sixteen
to eighteen inches in diameter will readily pass the pump, and by
applying the suction and excavating pipes directly to the removal of
surrounding disintegrable material large boulders may be sunk below the
required depth of the channel. As to the speed of excavating much
depends on the consistency of the material operated on.
The mechanism for accomplishing the foregoing results comprises a
suitable hull, a boiler of proper capacity, centrifugal pump and engine
attached, or a vacuum pump supply and discharge pipes for pump, a
force pump for excavating. by jet discharges, and steam engine to
operate the pump independently; also capstans and cables for controlling
the position of the hull, a shield attached to and surrounding the suction
dredge pipe near the top of the material to be dredged, of such area
that by its resistance to sudden vertical movements the effect of the
wave or other violent motion is obviated, and the plane of dredging is
uniform.
The submerged induction pipe may be curved and extend over the
hull at any place by being provided with suitable sleeve joints, and the
distance which its mouth shall extend below the surface may be
controlled by any suitable elevating apparatus; but I prefer to place

page_text: said pipe between the cylinders of a vacuum pump, and make it in two
or more parts telescopic in form, and to hang it vertically and elevate
one or more of these parts by any suitable apparatus, or lower them to
reach the bed to be excavated, suitable appliances being used to prevent
the oscillation of the pipe if desired. The dredge is placed over the
point and on the line of the material to be removed, and parallel to it,
in which position it is properly anchored. The suction dredge pipe is
then lowered to the deposit to be removed. The jet pipe is to be put in
operation simultaneously with the suction pipe, and the suspended
material will be elevated, and it may be conveyed into a scow or other
desired place.
In a modification of this Invention I employ a submerged hull or
traversing dredge. The hull is arranged by means of a water com-
partment to be sunk to the water bed, and will there perform (by means
of my improved mechanism and appliances) the same function as when
the hull floats upon the water. Air pipes and smoke pipes attached to
the hull project above the surface of the water, so that men may work
on the hull without inconvenience, and smoke or steam may freely
escape.
The hull is sunk by admitting water into the aforesaid compartment
by a suitable gate or valve, and it is removed from the said compartment
by means of the pump which throws the jet of water, or the vacuum
may be used for this purpose.
An important feature in the submerged dredge consists in air chambers
with communicating pipes, whereby by means of a suitable pump I am
enabled to convey compressed air from one part of the hull to another
part, and elevate any part of the hull desired to bring the excavating
and dredging pipes properly to the material to be removed.