Vicksburg weekly herald., 1877-07-27
VIeksbnrn'a VEater.Front.
scoTT's PLAN OF ARTIFICIAL RACK
HAP DAMb, OR DYKEs-COsT OF con

sTRUCTION, ETC.
Editor Herald: I send you q dc.
scFiptiOn Of the plan of the artificial
rack.heap dam or dyke, and the man.
ner OF building; also the probable ex-
pense OF securing the present point
above Della from further caving, until,
in the course Of time, Tuscumbia Bend
(if not preVented) would cut YOuug's
Point down TO the work and get BE-
hind 1t, by making another cutoff
from II to bend that must Of necessi-
ty, If not prevented, form where the
current strikes the Louisiana shore In
its rebound below Vicksburg.
The plan is based on the action of
the river itself, and is as follows:
With tow.boat and q double Get OF
barges provided with large rocks,
weighing from one to two tons each,
for anchors; each rock having hole
drilled through 1t TO receive bolt, the
hole to be say two inches In diameter,
the bolt having an eye turned on it aud
fastened In the rock by bending the
lower end proceed to the first large
tree growing on the bank above, con.
venient enough to be felled into the
river. The hat.bOats are each to be
provided with shears, derriCks, and q
capstan to work the falls. When the
tree is cut down II is hoisted alongside
Of the aAt-boAts aud the butt held only
high enough to enable the workmen to
bore an auger hole into 1t 10 receive q
square, bearded bolt. The bolt in the
tree should also have an eye on 1t, and
the two should be connected by bar
Of iron fastened to both. The bar
should be from four to eight feet long
to allow the anchor to bury itself in the
sand, and should have q link In the
middle to allow it 10 adjust itself to the
position Of the tree. The first tree is
dropped as close to the shore as posi-.
Bile 10 dead or slack water, and riveted
to the shore 80 as TO prevent the cur
rent getting behind it. A second tree
is anchored in like manner as close to
the frst as possible, so that their
branches will interlock, and third In
like manner, continuing thus as far as
necessary.
The dyke should start from the shore
at right angles with the shore, aud con-
tinue In that direction until the strength
of the current is reached, and then 1t
should be curved down in the direc.
lion in which it is intended the cur
rent should flow. When the first line
is down, a second line of trees should
be anchored on top of the first, aud II
that will not reach the surface, q third
line, aud In extreme cases Q fourth line
may be required but II is seldom that
more than two lines Of trees would be
required.
Now to apply the foregoing plan to
the present exlgency Of Vicksburg: II
is 5000 feet from the hard mud point
below the head Of the military canal
This mud point is above where the
main current strikes the shore, above
the main or Delta point, and affords q
good basis on which to commence the
fret dyke.
Commencing OF, or rather under the
mud point, run tho fret or upper dyke,
at least two hundred yards out at right
angles with the shore, and then curve
down two hundred or three hundred
yards fbrther. This dyke will be the
most important aud should be made
out of the largest trees that can be pro-
cured. From the soundings that have
been made, II will require about fifty
five trees TO each tier, and cay three
tiers, will require one hundred and
sixty five TO complete the whole. A
second dyke Of the came dimensions
would make the whole number of trees
required about three hundred and
thirty. The cost of q dyke Of this
kind will approximate as follows ;
Three hundred aud thirty rocks and
auchors (taking the report Of cost OF
rocks at the quarry as q basis, and one
hundred pounds Of IRON, as an average
for each fastening, 1t would cost five
dollars per tree, or 81 $50 for the whole.
II may be taken 90 an average, that q
steamboat, with o sufficient crew and q
proper amount Of barges, can put down
six trees per day but this will depend
on the steamboat. II she is properly
fitted for towing astern, the work will
be easier done than with q stern.
wheel.
The men required for six trees per
day, is as follows: Two choppers and
seven or eight holsters, 10 get the trees
ready, eight men on the steamboat; or
say, In round numbers, - men at $25
per month, $500; cost OF running boat
for officers and fuel $50 per day, 81, 500
per month; cost OF provision for %
men at 80 cents per head, Sl2 so. This
summarized, gives as follows:
32O anchors and chains, at s. per an-
Cost OF running boat and wages for
crew, with provisions for - men all
told $40 per day and for VA days.... 4,24O
Contingencies ....'...............'... lOu
Total for building two dykes, Of 100
Time required, "a days.
The foregoing plan is based on the
action ofthe river itself. Flrst, a snag
catches drift and farms o rack-heap.
This causes slack water below and
forms o bar, which In turn reinfOrces
the rack.heap and together they force
the channel IN a new direction.
do not claim that the erection Of
two dykes, as proposed, will bring the
channel back TO the old place, but they