The Cairo bulletin. [volume] (Cairo, Ill.) 1872-1878, 1878-02-01
yhe Bulleiin.
RIVER IMPROVEMENT.

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y RIVER IMPROVEMENT.
ps. Has. ID. Eads! Address before the
10. Louis Chamber Of Commerce.
W TO Mako q Clear Channel from
81. L8uis TO New Orleans.
nmatod cost OF the Proposed Im-
pr0yement.
'apt. Jas. b. Eads addressed the
,oiber OF commerce at St. Louis, on
.dnesday afternoon, on the subject OF
Improvement Of the Mississippi
er. His speech is full OF interest TO
/ people OF this section, and hence sc
olish itin full,
CART. EADs' RENAME.
Ar. President and Gentlemen OF The
change propose 10 explain the
tises OF some OF the phenouena and
uacteristics presented by The Missls-
pi river In the 1900 mikes OF It's path
y from 81, Louis 10 the sea, aud 10
.gest system OF improvement tor
portion oi it, 80 simple la plan and
tain in effect that il CAD nos fail 10
nDeBd itself To your Judgment.
lhe laws which control the river are
ong the siruplest OF which We have
-owl.dge, although the conditions al
ting their operations arc frequently so
'dified that its problems become very
npieX. Each portion 10 he improved
lseSuently requires 10 be treated ac-
ding TO the different circumstances
Getting ii. One general system, hows
er. will be peculiarly applicable. for
/. part flowing through the alluviai
triet, and il Is this plan, asa wbols,
lich ! propose to explain
THIs PLAS
10 simple that can safely promise 10
m one who Viii give inc his ciose AZ
itlon tor "A few nsOmcnts, TO some vi
: seemingly dull explanations that |
ist make st The start, that lie suaii
lhcien.ly understand tie principles on
iieh it rests 10 follow ne step by step
their logical application to the deepeu-
{ oi The riyer aud the lowering vi Us
pds. until the grand fact that II is en-
ely within our power 10 thoroughly
70 and guide lis vast volume, AID pre-
ut its destructive ovcrfogs. shall be
ed upon his mind as u CONVECTION,
ircely lees positiye than that which
lily assures him that the sh AIDES Vi night
il vanish wiki the dawn.
First let me call your attention 70 this
riZontai line, winch is intended 10
). The other one, slantiog upward
)n this end oil the iirst and rising
xper and sleeper, represents the sur
,r slope OF the river In food time.
iis point, the head OF the passes,
eve miles from the Gulf. is three feet
owe Its ulean level. Al New Orleans
is about sixteen ieet at Red River,
y ieet; al Natchez, siXty-six feet; al
lines Landing, about half way 10 st.
|uis, l49 feet; at Memphis, 22l; at
iro, 3ll, and ut ST. LJui: az feet
pve Inc level OF the Gull.
THIS LINE OF FLOOD sLoPR
90 the height Of the levees. So long as
femains ~ Its pre.eLt height Tie leyets
LIST continue 10 be above II 10 protect
land. Any treatment OF the river
at will lower this line will tend 10 make
Tees unnecessary. Ii IL can be lowered
as TO be below the surface Of the river
INKS, there will be no need OF them.
let me now direct your attention 10
remarkable difference existing 10 the
hde or inclination OF this slope in yarl>
parts OF the river. From New Or.
ms 10 the passes II Is not an isch and n
Ia per mule from the passes 10 Red
er, 900 miles, IL Is less than two inches
mile, but In the next GO miles IL raises
2 Is inches per mile and gets sleeper
I'll from Memphis to Cairo it exceeds
% inches per mile, and from Cairo TO
Louis 1t Is over six inches.
The high water mark at Cairo Is IL
8 above the land. II this slope could
roducs d from Red River 10 Cairo,
miles, only one quarter OF an inch
r mile. 1t would lower the floods NJ
Iiro 200 inches. or Iaore than sixteen
st. Yet. from Red river up, the slope
ddenly rises In the first sixty miles
Pm an inch and seyenseighths 10 nearly
rec and a quarter. Thus 1t Is here An
ch and three.eirhths greater per mile
Owe than II Ia below Red river. Low
q 1t be lowered:
THE CURRENT
the result of gravity, or OF the filling
alter from a higher toa lower level
nsequently the more rapid Is the fall
r. mile. the greater Is the force OF gray
developed by any given body OIL
ater. We see, then, tina, much more
roo must DO Developed by the water
love Red river than below II, and
her things being equal, we should OK
Ct 10 find the current much moro
pid above than below. But IL Is 70.
aikoble TACT that there Is 10 very nota,
= difference 10 the average velocity o
Q Hood current from Si. Louis 10 the
uli. The reason Of this ia, tina, thS
yer flows through bed Oi It's OWL
aking. What a sluggish current NJ.
posited yesterday, or 5000 yeara ago
rapid current will take up to-day, ant
Try onward to the sen. Hence IA,
yer, through its alluvial district, viii
be tolerate a current IlIst is too rapid
b Its needs. No engineer can perina,
nifty maintain one In II, for il IL bs
% rapid, It scours away the bed Of the
ger. and az the bed deepens, the slope
10 and the current must slacken. And
Ike manner, no engineer can per.
Rnently slacken the current, tor, II he
,cken II, II becomcs unable TO sustain
load OF sediment II carries. This Is
opped In its channel, and tho bed IL
bysied hy the deposit, and rs Ii Is elc.
sod, tho slope Ia s,ecpened, and the
FRONT must thereby be quiekcned
MIA.
Gravity b The force impellInr the
|fes. While The friction Of tho bed Is
ss TaE cRIEp ELEHryr
- retardb II. Consequently when
VatcF ms most fffctional resistance,
nnot hoyo ~ sfeepest slope TO over,
~ 1I6tapcex This we vii!
~ = A.