The daily Argus. (Rock Island, Ill.) 1873-1877, 1877-03-01

dykes, viz, That you must always begin
at the bottom and.build up to the surface
of the water, not begin'at the surface, and
work down. l do not think it is to our
| interest as steamboat men to oppose or
| fight against the engineer corps, but
rather try persuasion with them, and if
possible get them to cooperate with intel
| liget steamboat men for the good of all
concerned, and especially the object we
all have at heart, that is, the effectual and
permanent Improvement Of the great Mis-
sissippi river. Now allow me to submit
plan for the consideration of those inter-
ested, not presuming to say that is the
| best that can be presented by any means.
Where there is shoal or sand-bar to be
Improved | would run a dam of rubble
stone or loose rock on the side of the
river that has an alluvial bank provided
there is a rocky shore opposite), starting
the dam above the shoal water, and run
ming it in a gentle curve down below the
foot of the bar, aud extending the centre
of the curve opposite the shoalest water
out ID the river a sufficient distance to
confne the volume of water so as to scour
out the channel. The dam should be
built so as to be FIVE feet wide on the
crest and to be even with the surface of
| the water at a seven-foot stage, This
would allow the water to run over the
dam during high water, or at any ordinary
state, and the dam would naturally make
an eddy inside Of it, which would arrest
the sand and sediment and hold it there.
Then you would have your sand bars
where you want them, and your channel
would scour out in time for low water.
Where you have alluvial banks on both
shores, it would be necessary to build a
dam FROM each shore, opposite one another
or else rip-rap one shore, By thus con
filming the water it naturally increases the
velocity of the current between the dams,
and consequently would scour out the
sand on the reef, or bar, rapidly, and
make a good channel A dam built of
rubble stone FIVE feet wide on the crest
and seven feet deep, would have base of
at least 20 feet. The rubble stone would
accommodate itself to the irregularities of
the bottom, and would probably settle IN
the sand when the dam is finished a foot
or eighteen inches. The gentle curve of
these dams would conGne the water gradu
ally, and therefore would not give the
resistance that dykes thrown out at right
angles with the shore do Another i'm
P5rtant point is that, if you make good
channel through sand-bar by means of
dykes, you only displace the sand on that
bar to lodge on the next bar below. Rub
ble-stone can be found very convenient to
any of the shoal bars between st. Louis
and Cairo and, believe, can be delivered
on the dams at a cost of not more than
$3.50 per cubic yard. | confidentialy
believe that by building cams in this man
ner channel depth of six to eight feet
in low water can be secured and maintain.
ed between St. Louis and Cairo at a very
moderate cost Let us have this matter
fully discussed, and then let a committee
be appointed of such men as Jno A
Scudder, II. f. Haarstick, VIM. T. David
son and E. w. Gould, who are interested
IN the navigation of the lower river, and
let them decide upon the best plan to im-
prove the river, and then confer with Col
Simpson, corps Of engineers U. S. A.. in
regard to it, He will receive them like
gentlemen, and l firmly believe will CO.
operate with them for the public good.
Very respect'y your most ob't s'v't,
| JNO. B. DAVIS.