The New Orleans bulletin. [volume] (New Orleans [La.]) 1874-1876, 1876-02-25

What the Great Engineer Says
About the Mississippi
River.
He Can Set Cairo on q Hill and
Raise the Mississippi Valley
High Above Water.
Editorial Cor. Cairo Bulletin

Editorial Cor. Cairo Bulletin
WASHINGTON, D. c., Feb. 16.-Capt. Eads,
the jetty man, was on the cars. was intro.
duced to him.
"Of Cairo" he said: 81 am very familiar
with your little city. Years ago, when I was
q member of the firm of Eads & Nelson, ]
spent much time there, and some of the
pleasantest days of my life"
THE EADs JETTIEs.
"Your ietties are all that you expected they
would be?
Something more. But was sure of sue
cess when we undertook the work. Before o
year has elapsed after the time of driving the
first pile, We will have double the amount of
depth over the jettied pass and mere water
than there is on either Of the other Passes"
OF COURSE
A very confident gentleman, this baldhead-
ed engineer, but not Doas.ful. What he says
to you he says in modest, matter-of-fa fact
way, and you Immediately assent to all he as.
serts So, when he made this assertion, it
did not occur to me that the gentleman
speaking was telling me he was about to prove
himself the greatest of living engineers, and
replied to him with not a shade of doubt in
the tone of my voice: "Of course
CONVERTED.
Then he proceeded to talk "river" in such
a plain way that l became learned on the sub
ject without my consent, and before we ar
rived at Washington I was converted to the
belief that Cairo, and indeed all the country
below on the Mississippi, might be in effect
lifted above high-water mark-that, without
the construction OF levee, the whole of the
Mississippi Valley might be redeemed from
overflow and the channel supplied with an
average depth of twenty feet OF water from
the passes to Cairo, and fifteen feet from
Cairo to St. Louis
IAN astonishing assertion r you exclaim.
True; but Capt Eads has made it, and has
said he will stake his reputation upon it.
81 am" said he, absolutely confident
could produce this result at half the cost to
the government of the estimated cost Of the
proposed levees"
Snail endeavor to tell you by what argu.
ments he convinced me that he can do what
he sid To do so, life is not too short, out
this letter can not be made long enough.
BRIEFLY, HOWEVER:
II understood the Captain. he claims that
there are two theories of the Mississippi River
mprovement-one based upon the phiIoso-
ply of Humphrey and Abbots great work,
The Physics and Hydraulics of the Missis-
sippi River, and the other on common sense
and science
THE HUMPHREY THEORY Is
that the real bed of the Mississippi River,
upon which rest the shifting sand bars and
mud banks made by local causes, is struct-
ure of hard, blue clay, quite unlike the pres
emit deposits of the river, and which resists
the action Of the strong current almost like
marble; that therefore the bed of the river
can not yield, and if the velocity of the river
current be increased sufficiently to compel an
IS k10 IL : h.
larged by an increased caving of the banks;
that, consequently, the closing up of outlets
by levees or otherwise has tendency to raise
the flood line, and that the making of outlets
has tendency TO lower the fooc line. But,
from the outlet system, according to the
"no assistance in retaining
the alluvial region from overflow can Judi.
ciously be anticipated. Though correct in
theory, no advantageous sites for artificial out
lets exist.
Thus We find the Humphreyites claiming
that the current can not scour out marble
hard blue clay of the river bed, and that the
surplus water can not be carried off by out
let's. Their conclusion is, therefore, that to
redeem the Mississippi from overflow, high
levees must be built from the mouth Of the
this work will be SAG, ZOO, COO; and after it is
done the expense of keeping it in repair will
amount annually to a very considerable sum.
THE EADs THEORY Is
that the river flows in q bed composed of its
deposits, with dimensions regulated accord
ing to its own needs; that this bed is deep
ened as the volume of water in it is increased,
and elevated, or filled up as the volume is de-
creased; therefore, by reducing the high-wat
channel of the river to an approximate uni
formity of width, thus throwing down its
slope to the Gulf q greater volume of water
with swifter current, the shoals which inter-
rupt its navigation might be removed, uni
formity being given to its slope and current,
The caving of its banks be almost entirely
prevented and its high-water line be reduced
in such degree that levees would not be
needed.
This result the Eadites claim, backing their
assertion by argument that, in my opinion,
can not be contrOvorted, may be obtained by
! judicious system of cut-offs and dykes.
GIN THIS Way"
said Capt Eads, with great emphasis, 81 the
food-slope can be safely and permanently
lowered above each cutoff the entire alIuvial
basin from Vicksburg to Cairo be- lifted, as it
were, above all overflow, and levees in that
part of the river rendered useless. The food.
line at Cairo is ffty-one or fifty-two feet above
the low water line It can be reduced at no
great expense, to forty feet, and thus leave
Cairo and all the rich country around it on
high ground There can be no question of
this fact, and it would be we'll for those most
deeply interested in the matter to ponder
upon my confident assertion before rejecting
it, for the increased value that would be given
to the territory that would be thus secured to
the uses OF man can scarcely be estimated"