The New Orleans daily Democrat. [volume] (New Orleans, La.) 1877-1880, 1878-02-04
IMPROVEMENT OF THE MISSISSIPPI
RIVER.

Editor Democrat-I see an article in the edi-
torial columns Of Tuesdays PicdHtti,s headed
lsevee Improvement and Channel Improve
ment attacking the St Louis Repatttcm, for
champlOning the cause Of Capt. Eads In his
channel Improvement scheme. As | am an
advocate of Capt. 1lads' plan, do not like the
several errors which the Picdgt.,,e has made
1u no unanswered.
He fitst stated that the building Of levees
would Ecuur out d deep channel as elIectually
as the proposed jetties.
According TO that theory. the picuv,t,,e might
have made a good thing by taking u contract
tainly could have underbid Capt. Eads and
made money. IL seems to me 1t would have
been much cheaper TO have built a levee ON
each side of the pass.
Current Is what Ia needed for seou ring, and
when you have current, then additional bulk
of water Is beneficial for carrying off the mud.
Were this otherwise, all we would have to do
N order to deepen pond would be to build a
OF water.
Again, the picdy'ose says that IT is difficult
10 conjecture how Capt. Eads' ietties would
tend to lower the high watfr mark.
depth at New Orleans al 100 feet aud al the
mouth at 20 feet, we have a slope of 100 feet in
400 miles, or an average of IL feet per
mile Surprising the slope to be gradual, this,
OF itself, would be an immense check to
the current; besides this. as the river gets
more shallow it must of course widen to hold
the water. This briggs another check to the
current, namely, the greater amount of frc-
tion of the water against the bottom, arising
from a greater extent of bottom Now, the
swifter the water the more serious these
checks become. This is the reason why, in
high water, they back the water, higher IN pro,
portion than III low water. / have supposed
IN the above TINT the slope was gradual fNhm
New Orleans to the sea- whereas 1t IL well
known that such liz NOT, the case. On the con-
lrAs tt,t Ill.,.
abrupt and the river much wider than would
be required were 1t not SO abrupt. Thus the
two checks are increased by every variation
from the natural slope. What has been said
with greater reason of the river above that
city, as the he'd, | believe, Is more insecure as
You go up the river: and also, not being SO
close to the sea- you can aower the high water
surface little more.
Now, any system of works that will tend to
remove these checks to the current will lower
the height Of the water at oil times, and In a
greater proportion In high than In low water.
capt, Eads has demonstrated that he can do
this practically BY the success of the ietties |
aud Theoretically In an Article written by |
him in the Pfcnyane some time back and t. |
for one, would like to see hin have a portion |
OF the river to make the trial, backed by
good appropriation.
/ will mention, in addition. the experience
of planters on the Lafourche. Whenever a
erevasse occurs on this bayou a few feet of |
are 1UTIUeu JllSg Dp1OW 1t, The current
being slaelened little by the amount of
water below the screvasse being diminished.
When the ,crevasse Is closed and the water
thrown back into the bayou the height is
greater comparatively above this deposit than
beloweit, although the same amount of water
flows In both places, and the channel is the
same This can result from nothing else than
the check given to the current.hy the deposit.
This is removed after a few days by the cur
rent, and the stream resumes its regular
height
IL does not need much stretch OF the imagi-
nation ITO look back to a periodAwh the
mouth of the Mississippi was 269 miles
from its present one Calculating from
the slope OF the banks, we see that at a loy es-
innate the land mast now be at least 20feet
higher than sea level where formerly it wasn't
let us take point above this former mouthl
at o distance equal to that from New Orleans
to the present mouth the height at that l
point must also be at least % feet above it's
former height. As t&is period is not so re-
mote as would lead us to suppose that there
could have been much change In the size OF
the river, lin fact IL it Is true that clearing up
q country dinainishes the rain fall it must at
that time have been larger, there must have
been q channel of about the same size, or, in
other words, the banks having been 90 feet
lower. the bottom of the river must have been
On an average also 20 feet lower. Therefore |
the bed of the river must have been raised In
the same proportion as the banks.
Now, If you prevent the banks from rising
by thorough system Of levees TO prevent
overfsows. the bed OF the river not being dis
gradually rising and the leYees would have to-