Thibodaux minerva. [volume] (Thibodaux, La.) 18??-1858, 1855-02-17

any .rise less than the greatest will not till the
channel Again when there many outlets, the
channel Of the river is exactly suited to the amount
of water remaining in the river, after the outlets
or suiccs filed, or in other Words the river mas
not the capacity to accommodate the whole amount
of water during floods the excess therefore es-
capes. 1t will thence be seen that when great
feed comes down suddenly, it finds channel too
small for its wants. it must overflow, or escape,
either by its old and legitimate outlets, or 10y new
ones termed crevasses Hence, usth outlets we
have high water more trequently than without
them, for the reason that less amount OF water
fills the smaller channel than is required to fill
the greater. The general plane of the surface OF
the Mississippi, cannot be elevated above certain
point, governed by the relative height OF the head
and discharge, unless the water is obstrncted OF
damned up, at an intermediate point This Is
DONE the river is obstructed whenever any outlet
is made Or suffered to exist, below Red River, be-
cause here is the last increase given to the amount
coming down the river; here is the largest amount
of water in the river at any place; and accordingly
the greatest cross section, the largest channel.
Now any dimnution of this channel is an o''struc-
ton, and every outlet below, whether Legitimate,
as the PIaquemine and Lafourche, accidental, as
nrcase of crevasses does diminish the channel, as
has been proved, by the U. S. Survey OF the Mis-
sissippi and by cross sections taken by many per-
sons. The Bonnie Care cutoff afforded IL remark
able example illustration and proof Of this. The
cross section of the river above was 1885, square
feet and below the crevasse l52, 443 square feet or
46, 29l square feet less than above, which was the
cross section of the discharge of the creyasse ITSELF
or $4,000 square feet, as taken by Mr.. Elet. So it
is everywhere and so it always will be, science to
the contrary, in favor of outlets notwithstanding.
We thence conclude, that were the bayOus Pla-
auemine and Lafourche both closed, that the Mis-
sissppi, from the Red River to the Balize, would
have channel suited to the greatest amount OF
water that ever came down at time large enough
to accommodate the greatest foods, without over
flowing, or rising above the high water mark, all
floods less than the greatest, Tor in other words
whenever the water came down more gradually
would be Accommodated by the channel easily,
without reaching the high water mark. We should
therefore be less liable to overflow than now.
do consider the closing of Plaquemine and the
Lafourche as the two greatest improvements that
can be made in Louisiana. What a vast extent OF
country could be reclaimed, and brought into
market and cultivation, and at how trifling cost;
beneftng the river at the time in place OF in-
iuripg it. These two Improvements will be carried
out, and soon too The tide of public opinion is
changing; the "outlet men" are few now. The
outlet now being made on Lafourche, if only car
ried out, will settle the whole question of outlets
and their advocates more efectually than all our
arguments. for one, am anxiously, impatiently,
awaiting the effect Of this improvement ~ on the
Lafourche The first effect will be the closing by
deposit of the main channel of the Lafourche; the
next the closing of the outlet itself by deposit.
This outlet will discharge into shallow lakes from
8 to feet Deep extending some forty miles to the
Gulf Mexico, all at tide water level, of course.
wherever the Lafourche water reaches tide water,
it will deposit its sand and clay, which will form
islands and soon clog up the outlet.
The time is coming, coming fast, when you and
and the rest of the community take ride
from Donaldsonville, ria Thibodaux (no longer IN
the diaace) to New Orleans, through four hours.
Yours truly, G. W. r. BAYLEy,
Engineer n. o., o. & G. W. R. R.