IMPROVED MEANS AND APPARATUS FOR SCOURING TIDAL AND RIVER CHANNELS
Year: 1879

page_text: LETTERS PATENT to Pryse Protheroe, of No. 38, Leadenhall Street, in the
City of London, for the Invention of "IMPROVED MEANS AND APPARATUS FOR
SCOURING TIDAL AND RIVER CHANNELS."
Sealed the 18th November 1879, and dated the 26th May 1879.
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PROVISIONAL SPECIFICATION left by the said Pryse Protheroe at the
Office of the Commissioners of Patents on the 26th May 1879.
PRYSE PROTHEROE, of No. 38, Leadenhall Street, in the City of London.
IMPROVED MEANS AND APPARATUS FOR SCOURING TIDAL AND RIVER CHANNELS."
My Invention relates to means and apparatus for scouring tidal and river
channels, or clearing them of mud, silt, and other such obstructions as can be
removed by the force of the current, my object being to direct the natural current
in such a manner as to disturb the obstructing material at the bottom, so that it
is carried away by the stream to be distributed or deposited at a distance from
the obstructed locality.
For this purpose I provide a vessel which may be of rectangular shape, like a barge,
and under the bottom of this vessel I provide a flap or second bottom hinged at
its front, so that its back part can be lowered to within such distance from the
bottom of the channel as may be required. The vessel being moored with its
head to the stream, the current is deflected by the inclined flap so as to impinge
forcibly on the material at the bottom of the channel, disturbing and carrying it
away. The flap may be in parts hinge-jointed together so that in shallow channels
a portion only and not the whole may be lowered. Also the whole flap or its
jointed parts may be more or less curved so as to give a better direction to the
current deflected by it. The flap may be made cellular, of sufficient weight when
the cells are charged with water to sink in opposition to the current, but capable
of being lightened for the purpose of raising it by forcing air into the cells to dis-
place the water. Otherwise when a light flap is used it may be held down against
the pressure of the current by struts working through swivel eyes on the body of
the vessel which is provided with the necessary gear for raising and lowering the
flap, and the ordinary fittings for mooring and navigating.

page_text: Fig. 1 represents in side view a barge or vessel arranged according to my Inven-
tion for scouring the bottom of a channel; Fig. 2 is a part longitudinal section;
Fig. 3, a part plan to an enlarged scale of the front part of the vessel. A. is the
flap or second bottom hinged to the front part of the vessel's bottom, so that it can
be folded close up to the bottom, or let more or less down therefrom to take an
inclined direction. It may have flaps B hinged at its sides so as to hang down-
wards when the apparatus is in action, or to be folded up against the sides of the
vessel when the main flap A is raised. The raising and lowering of the flap may
be effected by ropes or chains when it is made of sufficient weight to resist the
force of the current directed against its inclined face. It is however preferable to
make the flap of light structure and hold it at the desired angle by struts C, which
can be moved up or down simultaneously by pinions on a shaft D gearing with
rack teeth on the faces of the struts. The flap may be single, as shewn in Fig. 2,
or it may consist of several parts hinged to one another as shewn in Fig. 1, in
which case there is a second flap B₁ hinged to the front flap and worked by a
second set of struts C¹. The barge may be provided with a front paddle E by
which it can be propelled from place to place. This paddle can also be used when
the apparatus is at work to relieve the moorings and to increase the current
deflected by the flap.

page_text: Having thus described the nature of my Invention and in what manner the
same is to be performed,
I claim,―
Scouring tidal and river channels by means of apparatus consisting of a barge or
vessel having hinged to its bottom an adjustable flap or second bottom, whereby the
current is directed so as to disturb and wash away obstructing material, sub-
stantially as herein described.
In witness whereof, I, the said Pryse Protheroe, have hereunto set my
hand and seal, this Twenty-sixth day of November, in the year of our Lord
One thousand eight hundred and seventy nine.
PRYSE PROTHEROE. (L.S.)