The Greenville times. [volume] (Greenville, Miss.) 1868-1917, 1890-08-23

LACKING dctual measurements. they
supported the proposition by a
very ingenious method OF Indirect
proof, which showed in part, but not
completely. the futility of outlets as a
means Of flood relief. In the case OF
this year, just cited, an actual outlet
was in operation, and all the quantities
involved were directly measured. Ii
is a gigantic clinic upon an aggravated
case of the outlet plague, and shows
that as a means of incubation against
oyerfows the outlet is distinct fail
ure. 1t has long been conceded that
nothing in the way of benefits could
be looked for from an outlet, except a
temporary local depression of flood
surface proportionate to the amount
OF water taken out, and now it appears
that this last surviving hope is shatter-
ed. The relief afforded is so tritliug
as compared with the effort and risk
of obtaining it, the effect SO insigni6-
cant as compared with its cause, that
If all the evils of outlets were discredi-
ted, there would still be no excuse for
making them. A mountain in labor
to bring forth a mouse does not sur
pass such project as an example of
fruitless endeavor.
The size aud form ofthe channel are
the result of the effort of the stream,
the size determining its suilicincy as u
flood chain and the form its usefulness
as route for navigation. That both
arc defective is not because the energy
is lacking, but because Is II misdirected.
1t has already been intlmated that less
energy is required to prevent a deposit
than to remove 1t after it is made. So,
also, 1t is far easier to maintain chan
mel once formed than TO open new
one. The river has ample energy to
maintain channel Of proper naviga-
bio depth and discharging capacity if
1t can be made to work, as every
agency should work to the best advan-
tage and,without waste of effort. That
IL does not so work is due to the fact
that the discharge and elevation of the
surface are mementarily changing, and
with them the positions of bank lines
and the location and direction of the
line of greatest velocity and maximum
effort. No sooner Is sufficient chan
mel obtained in one place than the cur
rent leaves II to be obliterated by de-
posits, while the work which would
have easily maintained it is wasted in
securing out a new and inferior one,
or perhaps dissipated among several.
Every mile Of the river is a witness to
the truth of this proposition, since the
places where the thalweg is stable in
position are invariably good and those
where II is shifting are invariably bad.
No exception to this rule can be found
Cairo and the Gulf.
What nature has failed to do, and
what remains for man to accomplish in
order to fit the Mississippi river to bis
wants and uses, is assumed up In the
one word control. Guide the current
as the skillfnl workman guides his
tool and 1t will not fail to carve out a
channel commensurate In sizo with the
magnificent agency employed and
worthy of tho greatest of rivers,
traversing and draining the most fruit
ful and prosperous Of countries.
The requisite control Is to be OBJ
tanned by partial reversal of the
present relations of the stream and its
bed, 1t has been shown that the chan
mel Is the ready servant, the stream
the imperious master. The inconstant
current seeks change and the SUBJ
servient shore retires before 1t. In
this respect, as regards the sidos of the
channel, the present relation of master
and slave must be reversed. The ser
vile banks must be strengthened and
melted TO revolt against their tyrant
and to impose q like bondage in return.
The current, no longer able to shift at
will, devotes its energy to securing
out the bottom, working constantly
on the same line aud always to the
best advantage, The stream acting
under such oonstraint will mould Its
channel to the largest attalnable size
aud dscharging capacity, and In the
form best adapted to the needs of
navigation.
Although this is statement of the
ories, il may not be aniss to interject
word az to practice. Type of struc-
lures have been evolved in the short
experience already had, which may be
relied upon to do the work expected
of them, and which can be constructed
at reasonable cost. A cavipg bank
eau be protected or secondary chan
mel closed with as much certainty as
pertains to the building of road or
the digging of q canal. Moreover,
these structures have been built at q
cost which will allow thom to be ap-
piled to tho entire river without OK
oeeding the sum which the city Of
Manchester pronoses to pay for canal
! connecting her with deep water in the
Mersey.
Uontrol by means Of protected banks
is complete and sufficient only so long
MS the river is within Its banks. When
it rises above their level the control
becomes partial and necessarily made
quate. In years of great floods the
surface of the water is above the nat
ural bank level from two months ut
Cairo to six months at New Orleans.
Without artificial restraint nearly one
third Of The entire discharge of the
river at extreme flood takes place out
side Its proper channel, as was the case
III 1882 above Vicksburg and In 1890
above Helena. The proportion de-
creases as the bank level is approached,
but the aggregate loss of volume dur
ing a flood period is enormous. 1t
has been shown that the fundamental
principle upon which the improvement
is based is the control of the water III
the channel. To allow large quanti-
ties to escape, reaching at times one
third of the whole, does violence 10
every idea which can possibly be asso-
ciated with the word control. Water
flowing in tho channel is the agency
of improvement, and when any Of 1t
escapes part of the potential goes
with it. and q corresponding measure
Of tho Improvement Is sacrificed. The