Memphis daily appeal. [volume] (Memphis, Tenn.) 1847-1886, 1875-08-10


the levee at Bonnet Care yields at once
whenever approached by anything like
a frsshet. Ii would seem that those
who are temporarily in charge Of the
levees at different points are truly neg
/ Lgent in not Strengthening the weak
uiaces IL the bends by lateral spurs.
Everywhere in European lands where
man Las enOeav0red to protect fertile
regions, the eng ,Ieers nave strengthen
ed their dykes by such q device. On
| the Po, at Parpanese, The most danger
/ ou5 efCsiOus are stopped by five spurs,
/ which form an Obtuse angle with the
! shore, TO which they are strongly Sc
/ cured. They commence with base Of
/ about twelve CATIONS, made of willow
! tWi-s filed with earth, which sustain be-
tween their angles eleven gsbiOns upon
which are placed ten more, and so on,
the humber in each course Iessenir z grad
ua.ly TO the top, where there ere oniy four
OF five. Here Is method that could De
employed dvaDtageOusly upon the Mis-
sissIppi, for here there is IOthing that can
be used for the levee save earth. Tnere
is no stone below Vicksburg, the whole
immense strength # the banks beir
nothing save ailuvium. Down below
this substance there is indeed an mex
Y,
which would be a very efficient matter
for covering the front Of the leveea, as
the HOilanders do with their dykes of
bItuminous earth. But there are diff
culties in obtaining this which seem al |
most insuruuUuntaOte. The system OF
cut-o1s has been pronounced impossible |
IS regards the Mississippi by very good
enthusiastically Humphreys and |
Abbott. The general idea of the cutoff |
Is to shorten a river by Strengthening it. |
This is done by cutting through the |
bends. or course it is obvious that to do |
this with any hope OF benefit, it would |
be absolutely necessary TO make the cuts |
from the beginning to the end The eX.
peGse would naturally be- something |
enormous, and is more than doubt |
ful if the experiment would sue
ceed. 1t was tried in the river
ArnO, by the famous italian engineer
NIvlana, IN the latter part of the seven
teenth century. Without going into de-
tail, 1t may be recorded that he laid it
down as fret principle that it was re-
qulsite to traverse and Obstruct the
course Of the ArnO in whatever way it
could be effected, and to compel this riv-
er to deposit its gravel and large stones
in It's upper bed. To do this he narrowed
and Strengthened it. He shortened it
three miles above Florence, and one
mile below, and the consequence was
that the bed CT the river was Individually
raised, and the stones and gravel were
carried further down than ever before.
\ OW the inevitable consequence of the
rise in the bottom Of q river is that there
VIII be greater hight Of the waters in
d )Ods, difficulty in procuring a vent
Tor the lnundatiOns Of the lower part of |
he stream, and an absolute necessity
or very thorough system Of high lev
9es. 1t is clear, moreover, that the Mis-
'issippi cannot be handled in such fash
on, The idea of cUt-offs may, there
ore, be definitely abandoned. The plan
II artificial outlets and reservoirs has
very much greater plausibility, and the 3
lme may come When it will be seriously
discussed. Artificial lakes that would re- !
.eIve the surplus fallness of the Missis-
ippi, and keep it low, would be of more
ssentlal service in mitigating the floods,
although they could not possibly pre- ,
'ent them. The Mississippi is in flood :
urIDg heightened periods, but the 7
reshets come from the tributaries like q
LASH. Whenever the river is in flood,
t their coming there must be serious
I0uOle al along the banks, because the U
OF the two is too much for i
ny system of levees. But if by art.fi- 4 \
ial lakes the river, when it has ten Z
ency to food can be relieved, then the Y
IaPue of the fEeshets of the Ohio and u
.her tributaries would be immensely :,
,ssened. AS for the artificial outlets, u
course'they could be made very ser.
Iceable; but the subject is very COM
lex and demands considerable know
.dge of localities. 1t is far easier to do Z
n the map than in reality. The Atcha- v
alsyR looks as if it could easily be made "
le channel OF the Red river. But he o.
hO has looked at them both will laugh CT
the idea that the puDy channel of the u
rmer could possibly contain the waters o
the other when in high flood. n
al