The Cairo bulletin. [volume] (Cairo, Ill.) 1872-1878, 1878-04-25


carrying sediment. To>day a channel OF
twenty-siX feet in depth, is through the
jetties, except for about 800 feet at its
mouth; but the uniformity of current
now through the jetties will scour that
obstruction out. IL Is wisdom TO treat
the river In such way as to avoid the
necessity OF leyees altogether. The first
effect OF an outlet is TO lower the flood
slope, but the result is bad and danger
Gus. He described Cublts crevasse, be>
low New Orleans, and another break
called the Jump" which was formed
thirty-iiye years ago. The river flows
more slugglishly below crevasses, or out.
lets, and Il deposit below them is the
result. The crevassos should be closed,
and the slope would at once be lowered.
Closing southwest pass and.pass a'Loutre
would result in lowering the flood line OF
the Mississippi river some two feet all
the way up 10 Cairo. The South pass
carries out only one-tenth of the waters
of the river, which is sufficient for it. 1t
was not intended that it should carry out
all the waters OF the river. 1t you dimin-
ish the size OF the Mississippi, you raise
the slope ultimately. This is natural law.
As long as you lcaye the wide places,
you cannot hope for any Uniformity in
depth or improvement in the river. The
friction is the chief element that retards
the flow OF the water, and this is greater
in proportion to the width OF bed in con-
tact with the water, thence sleeper
slope is created by the depositing action
of the river at all the wide places. When
these are reduced to their normal width
the bed will be dcepened and the slope
lowered, and levecs rendered less necUs>
sary,
THE OLD LEvEENBUILDING PLAN
must ultimately be abandoned, because
il requires the wide and shallow spaces
III the river, which are the fruitful and
only cause OF cayiDg banks and cur-otls,
TO be incl0sed within the levees, and
hence the cavlng and cut>Ofis must cons
tinue and the destruction of the leyccs
must follow. Once bring tho highs
water channel to an approximate mi.
t0rmity OF width and the caying Of the
banks will be- reduced to insignificant
proportions. Narrowing the wide places
| Is a thing much easier accomplished than
the rip-rapplng or mattressing of the
banks, because 1t requires no work to be
done except In shallow water. Where
the river is deep it is already narrow.
The great objection to the levee system,
he argued, is not tho present amount
needed tor absolute projection from the
near floods, Tor four or five millions
would insure this, but it Is the leyees
which must cave in from the cause above
named. Remove that cause and the
levees can be cheaply maintained, but
when the cause of the caving is remove d
the flood slope of the river would be
found to be lowered, and therefore the
leyees would be useless. The cost OF
such system of improvement is mere
nothing to the value OF the benefits
which would flow from it. 1t is bring
ing deep water up into the very heart
OF the Mississippi valley. The cost
would not be oneshalf what the govern.
ment has spent on the Union Pacific rail.
road. The system that is proposed is
exactly the opposite to that recommend
ed by the United States engineers.
CASCADES.
Captain Eods said: "Y GU have doubts
less heard 1t predicted that cascades will
be formed, US result OF this improves
ment, near Cairo, in the Ohio and the
Mississippi. This prophecy is made by
an assistant OF Colonel simpson, United
States engineer, at ST. Louis. have not
learned that his professional success has
yet earned for him any great share OF
public confidence, and inasmuch as the
same person came prominently to the
front In 1874 with an essay to prove that
the ietties would be failure, l think
his predictions relative to cas-
cades will carry but little
weight. lie belongs to the school OF en-
gineers who strove 10 force the Fort St.
Philip canal upon the country, instead
OF the jetties, and who urged the build.
ing OF canal around the eastern end OF
the st. Louis bridge, at cost OF So ,000,-
OOO, so us to save three or tour steamboats,
IRON the Inconvenience OF having to lows
er their chimneys. would not wonder
much II the same party should propose u
canal below ST. Louis TO avoid the diff
cult problem he has been wrestling with
for the past few years at Horselail bar.
should cascade occur, however, q canal
VIII be the legitimate remedy to get
around 1t, and | pledge my best efforts in
iaVor OF their building one. The talk
about cascades Is the merest twaddle.
You have been told that eight feet is alf
we want below ST. Louis. This Is prob
aply all mat the owner of u barge line
wants when he has good thing as the
river now Is. But when such statements
are made, 1t Is well TO look at the interest
which prompts them. Impartial system
Oh Improvement can possibly be perman-
emu, ior 1t will not remove the wide places
Whlcii cause the cavlng banks and shift
ihg channels. Remove them and Won
VIII nave at least twenty feet through II
low water, ana the snags will vanish with
the shoals, caying banks will practically
cease, and
ilh CHANNEL WILL BE PERMANENT"
Inc United States engineers advocate
!he ulnuslon OF water by outlets and rajs.
| ,l,g high leVees Ground the wide places
nc advocated It's c0nservation-eyerv
| crop oil it--in one channel of uniforw
wldth, and the abolition of ali the vida
places, the closure OF the outlets. and ' !,
necessary the closure Of the island chnieS
ihey propose to attack the bank NJ rho
river with shovels and wheelbarrows 't 70
accommodate Its anticipated elevation TON nv
or dozen feet higher than ever before
lie proposed to set the river TO work in
the bottom OF Us bed, as he did at tho
iellles, and, while deepening il for tho
peheilt OF commerce, to lower its naughty
caest forever. They provide for A river
c car1, threateningly above the land, A
, ,.hI,o WI source OF terror and anxiety,
~, "n LILY nv proposed that its vast volume,
W AL the grandeur of lts miphticst Hoods
shail DC viewed with an admiration de-,
vod OF fear from happy homes safe
above its surface.
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