Improvements in or relating to Devices for Controlling the Shifting Action of Moving Water on Land.
Year: 1890

page_text: Date of Application, 8th Jan., 1890-Accepted, 1st Mar., 1890
COMPLETE SPECIFICATION.
Improvements in or relating to Devices for Controlling the Shifting
Action of Moving Water on Land.
A communication from abroad by GEORGE H. HENSHAW, of Brooklyn, in the County
of Kings, and State of New York, United States of America.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street, Manchester. both in the
County of Lancaster, and 323, High Holborn, in the County of Middlesex, Civil
Engineer, 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:
This invention is in the nature of a means of controlling the shifting action of
running or turbulent water on land, by which river channels may be formed and
preserved, bars off the mouths of deltas removed and the channels through deltas
deepened and preserved, sea beaches repaired and protected from erosion, shifting
shoals fixed, and estuary lands reclaimed.
Heretofore, it has been attempted to accomplish these results by obstructing the
movement of the water outside the portion of land or bottom to be protected.
Thus, in deepening river and delta channels, stone jetties, mattress-work, and other
rigid and unyielding structures have been arranged along the sides of the channel
with the intention of confining the current and causing it to scour out and deepen the
channel.
In some cases, these obstructions have been made slightly permeable, with the
hope of catching some of the matter suspended in the moving water, and thus
preventing its deposition in other and undesirable places.
But in every case the obstructions have been unyielding, to resist the force of
the water and compel it to take the required course. This rigid resistance develops
an eddy-like reactive force, which is greatest alongside the obstructions, and thus
causes the rapid undermining of the obstructions, and the formation of the channels
so close thereto as to be dangerous to navigation, while no provision is made for the
suspended matter, the greater part of which is carried along with the current and
deposited in different places as the height of the water varies.
The improved mode of controlling the action of the water so as to obtain the desired
results consists in slightly checking, without obstructing, the movement of that portion
of the current or turbulent water outside of the part of the channel or bottom to be
protected, so as to cause the deposition of the matter suspended in the moving water
heneath the checked water and the thus gradual confinement of the water to the
desired course, which is thus by degrees deepened by the scour, while the parts of
the bottom beneath the retarded water and outside the same are built up by the
deposit. This is accomplished by means of an artificially constructed flexible and
permeable submarine barrier anchored upon bottom outside the part to be protected,
as and for the purpose hereinafter more fully set forth.
To the end that the invention may be fully understood, the mode in which the same
may be carried into effect will first be described in detail and then its distinctive
features will be pointed out in the claims.
Reference is to be had to the accompanying drawing forming part of the specifica-
tion, in which
Figure 1 is a diagrammatic plan view representing the improved means for con-
trolling the shifting action of moving water, applied to the preservation and deepening
of two adjacent river channels.
Figures 2, 3, 4 and 5, are detail views of devices hereinafter referred to forming
part of said means.

page_text: .
F
Like letters of reference designate corresponding parts in the different Figures.
A A¹ designate the opposite banks of a river, and B B₁ two natural channels therein
to be preserved and deepened.
t
To effect this, submarine barriers D are anchored, formed (as shown in Figures 2,3,4
and 5) of a rigidly constructed base E, and a flexible, permeable fence F, attached
to and rising from the base, upon the bottom, along opposite sides of each of the
channels B B, about in line with the direction of the current, as shown, the height of
the barriers being made about one-third the depth of the water where they are
anchored.
Each barrier D is, by preference, formed of a longitudinal body, composed of a
number of independent sections D¹ of uniform height, as that illustrated in Figures 2
and 3, and of a series of wings D2 projecting outward from the body and inclined
with the current, each wing D2, as well as the down-stream end section of the body,
vanishing in height toward its outer end according to the desired slope of the sides
of the channel bottom.
The base of each body section D' and wing section D2 is, as clearly shown in
Figures 2, 3, 4 and 5, formed of longitudinal wooden stringers H, rigidly connected
by wooden cross-beams I, and along the top and bottom of the latter are strung
inner and outer pairs respectively of stout wires J J¹, with which are securely
entwined willows or other light straight brush, the upper parts of which are interlaced
diagonally so as to form the permeable and flexible net-work fence F, lengthwise of
the base.
The bases of the several sections D1 D2 are joined together by flexible ties L,
Figure 4, so that the base E of the whole barrier can conform to the general shape
of the bottom.
It is preferred to anchor the barriers D on bottom by placing slabs of clay upon
the base, as indicated in Figures 3, 4 and 5.
The wings D at the upper ends of the shore barriers D are shown, in Figure 1,
continued to the shore and protected from undermining by mattress-work M, at the
foot, while the inclined wings D2 at the heads of the mid-stream barriers D, are
shown continued to a meeting, and protected from undermining by separate barrier
wings N, arranged in front of them, and by a rigid cut-water O, formed of piles, one
of which may be elevated above water to serve as a buoy, and which are driven in
front of the barrier-wings N.
The winged permeable and flexible barriers D effectually serve the purpose of
checking the current flowing thereover, by offering a diffused resistance which is
reinforced naturally by the deposit produced and retained by the permeable barriers,
and as there is no obstruction, there is no reaction to disturb the deposit.
If the deepening of the channel produced by one set of barriers is not sufficient
when such barriers have been silted up, other sets of barriers may be then placed
directly above the first to continue the process until the desired depth is attained.
In applying this means to fixing shifting shoals, preserving sea beaches, reclaiming
estuary lands, and the like, the same general arrangement of anchored flexible and
permeable submarine barriers is employed, modified according to the various con-
ditions met with.
My correspondent is aware that it has been attempted heretofore to improve
waterways by placing permeable dams of brush and of separate trees and clumps of
brush anchored to the bottom at the sides of the water-way so as to divert or
contract the channel through the accumulation of sediment in and around the perme-
able dams, but owing to the irregular structure and partial resistance to the current
of these brush dams and the oscillation of the dams made up of the separate trees or
clumps, the erosion is irregular, variable, and usually destructive.
Having now particularly described and ascertained the nature of the said inven
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondent, I declare that what I claim is :-
In means for protecting land against water erosion, an upright flexible reticulated

page_text: fence of regular structure rigidly secured along its foot to a frame-work or base-
anchored upon so as to partially cover the land or bottom to be fixed, substantially-
as described.
Dated this 7th dox of Ion 1890
WM. P. THOMPSON & Co.,.
Agents for the Applicant.