New-York tribune., 1877-05-05

little at first but A. il met the Gulf waves, giving
mn more and more of its burden. Tho
bar thus formed began a little distance inside
the mouth, and slopcd up gradually Tor
mile. continuing for three-quarters of mile fur
thcr m n vast mud plateau and terminating with
sharp descent into deep water The problem was TO
make the river carry off in year or two the mud IL
had taken centuries TO deposit and 10 restrain ~
from dropping any moro on the same place. How
far this problem has been solved will be understood
when [ say that the river has already picked
up four million cubic yards of mud rom
tho ton of the bar and carried it far
out 10 sea. To narrow and proong the chan-
mel 1t was necessary 90 build a jetty two and n
half miles long from tho end Of the eastern shore.
and another u mile and three-Guarers long from
the western bank The main structure of each In now
completed but much work remains to be done III
covering and facing them with stone. The Jetties
are constructed by first driving line OF guide piles
and then sinking against the piles number 0i mat
tresses of willow boughs bound together with planks
png one mattress on top of another until the sur
faco of the water is reached. The top of this sngu-
lar wall is covered with broken stone, apron-mat-
tresses arc placed along the river side, and moro
stone thrown in the slope thus formed. The mat
trcsscs arc 100 feet long, Dig feet thick, and from
80 10 90 wide, the lower ones being the widest.
/
which are driven at intervals of about three feet
apart stout hickory poles. Willow bonghs II or -
feet long nre piled on and the mattress is bound
together by panks placed crosswisc ton and fast
encd to the ends of tine upright poles. When COM
pleted tlc mattress is slid off the ways into tho
river and towcd down 10 the spot where 1t Is to be
sunk II barely floats. and II gathers the nVer-
silt very rapidly it will sink of IT'S own accord in
day or Two. few stones thrown on it are sufficient
TO scud it down As it Is quite flexible, IL ils itself
readily TO the inequalities of the bottom
SUCCESS or THE WORK.
ssoon ms the first tier is down. the water chcckedin
velocity, deposits bank Of mud on the outer sIdr'
which s increased by tho action oi the sea- Wlch the
wall il raised higher and sOidiicd Instead ot I'M
derrnipiup the jctty, rs was predicted. the river.
running more slowly against its sides than III mid
channel. fills mp the porous structure with sediment
and builds mud wall along its face. Wing dikcs
10 houumb,r of four five on each side constructed
like the c,fjcs have been thrown out TO narrow the
channel od increase the velocity Of the current so
ms TO hasten il in It's woil, Of securing down the
bar The jcttics run strongest ont for about nan
a milc and then bend to the westward, 80 that the
sea-curren running from cast to west "iil not StIkr
into the mouth. Little is seen Of them above the
waters surface except The top of the plies, save
where here and there the willow twigs have sprontod
and made stnp of bright green color on tho yel-
low waves
The theorists who were hostile to Capt. Eads's I'M
dcrlaking declared that q new bar would be formed
outside thc month OF his ic!ties. There Is no cyi-
dcncc AS vet that such formation has begun. Tho
westerly current sweeping with increased force
around the ends Of the iettics seems TO carry most
of the sediment of. Some is no doubt d'po,tod,
bat ihc process Of budiue mp new bar in tic deep
water b,yond tho old bar will not go fast enough,
il IL believed TO cause any anxiety for At least cen
,1l.y to come II may be necessary +" proimg the
ic+tcs across now bar. but that Will be question
for remote generations. The work Of opening the
river viii be accomplished by the present constnc-
tions.
An army officer whom met in New-OrcanS yes
tcrlav said that the severe test o the Jciics would
come I'm two or three months when the river brings
down tbc coarse sand of tic Upper Missouri II
thrrc should be no accrelious on the bar, then he
thought the success Of the enterprise would be
amply demonstrated. Soul-Wo-t Pass would .hon
I De allowed 10 fll up aud III the shipping would
| como fhis way. Going out today ON q tug to Che
.ra-c.d Of the ietGcs and Observing the gtrnngth
and velocity Of the current, could src no reason
why the river after bringing the coarse sand dis
taucc or two or three thou-aud Eilo should di"p
bclo.,i /. reached the open GulL The only remain
iug do1ht as 10 the utility Of the work have heard
cHpf' '' concerns "s j.. .I'''.'.'' ~ - ''''' 'N
some That The worms viii In time eat the willow
braurhes and cause the irttics to crulie. In rply
10 this objection Col. Andrews i've Chief ruaiuccr
saws that the Worlds only live in salt waior. and
that f. +. only during short period in each year,
when The nVrr il F'i! '""' '"a' 'n' '''- "'''i
washes hc jcttc- sufficiently 10 give 'h'W ,h1l'"
IN o,f t,c yy,iIo,ys What iitte damage they rgu
l-..f ...,.f t.,, I l,.y mot tl,.,,l.
d" l' 'u'h II ",''I 'P''' VI '''' "' '' "'' '''.''
VIII prove Serious.
PORT T,l.i4aliitlc colony OF workpeaplc, Grcwcu,