PLAN FOR DRAINING THE MISSISSIPPI LANDS. 
149 
of all the elements furnished to plants by the soil, 
and ministering to their nourishment, the phosphate 
of lime, or, rather, the phosphates generally, must 
be regarded as the most important.” Hence the im¬ 
portance of furnishing soils with alkalies, alkaline 
earths, and human urine, which abounds in sul¬ 
phate of potash and soda; and phosphates of soda, 
ammonia, magnesia, and lime. On the subject of 
furnishing soils with the foregoing inorganic sub¬ 
stances and of their great value, in rendering them 
productive, see Beatty on Agriculture, pp. 225— 
230 
Lime is one of the most valuable alkaline earths, 
and the means of producing it, in limestone soils, is 
almost unlimited. It not only serves as a substitute, 
where other alkalies are deficient, but in its caustic 
state is the means of opening stiff clay-soils, and 
setting free their alkalies. Lime, judiciously ap¬ 
plied, is therefore of great advantage to soils de¬ 
ficient in alkalies, and other mineral elements. 
From, the views already presented, it will be rea¬ 
dily perceived why the shell-marls of Virginia and 
other Atlantic states are found to be such valuable 
manures. But I have already occupied too much 
space, and will conclude, by mentioning the fact, 
that Johnston, the celebrated agricultural chemist, 
“ refers to a very fertile soil , containing less than a 
half per cent, of organized substances, but with a 
full supply of the proper inorganic substances; and 
to two other soils, having more than twenty-five per 
cent, of organized substances, which were barren 
and unfruitful, because of an almost total deficiency 
of some of the most important inorganic matters, to 
wit, lime, magnesia, potash, soda, phosphoric acid, 
sulphuric acid, and chlorine.” Nothing can more 
strongly show the importance of inorganic elements 
in soils, to render them fertile. A. Beatty. 
Prospect Hill, Ky., Dec., 1846. 
PROPOSED PLAN FOR DRAINING THE MIS- 
i SISSIPP1 LANDS. 
In reading the article entitled Letters from the 
South, in the March No. of the Agriculturist, I ob¬ 
serve some suggestions are thrown out by the 
writer on the practicability of draining the alluvial 
lands on the Mississippi, with the view of render¬ 
ing them fit for tillage. As this appears to be a 
subject of the utmost importance, in point of the 
economy and future prosperity of Louisiana and 
Mississippi, the following plan is offered, which, if 
not too expensive, it is believed, would prove fea¬ 
sible, and these lands might readily be reduced to a 
proper condition for the cultivation of cotton, rice, 
sugar-cane, Indian corn, and many other crops. 
It appears that all along the banks of the Missis¬ 
sippi, the land is highest, while the portion remote 
from them gradually subsides into irreclaimable 
swamps, and frequently into navigable lakes or 
lagoons, which communicate with the main stream 
by numerous smaller channels or bayous; that the 
natural elevation of the banks is not sufficient to 
prevent an overflow by floods, unless secured by 
artificial embankments, usually known on this river 
by the name of levees; and that these embank¬ 
ments often, though imperfectly, effect the object in 
view, as the porosity of the soil admits the passage 
of the water in consequence of its increased height 
above the adjoining lands, and proves fatal to the 
success of the crops. 
The plan I w T ould propose, to obviate these diffi¬ 
culties, would be, first, to construct entirely around 
the tract intended to be reclaimed (say two square 
miles), a substantial dike of a sufficient strength, 
breadth, and height, to resist the flow of the highest 
floods. This, I conceive, can be done by forming a 
series of ditches or channels, as indicated in the ad¬ 
joining figure, all dug to a uniform level, with the 
Figure 30. 
ones outermost of sufficient widths to furnish the 
materials for making the dykes. The last named 
ditches should be situated at least thirty feet from 
the inner slopes of the embankments, and all the 
ditches, as well as the dykes, should slope on their 
sides, one and a half to one, in order to prevent 
sliding or caving away. At the bottom of the 
outer slope, on the berm, or space between the em¬ 
bankment and the river-brink, willows and other 
aquatic shrubs may be encouraged to grow, to pro¬ 
tect the works from further encroachments from 
floods. 
In order to dispose of the water that may be ac¬ 
cumulated in the ditches, from rains, springs, or 
percolation, a self-acting flood-gate may be con¬ 
structed at a convenient point for discharge, as at a, 
which will always ke^ep open so long as the sur¬ 
face of the river is lower than that of the ditches; 
but as soon as the river rises above the surface of 
the water in.the ditches, the flood-gate will close of 
its own accord, and so continue until the river 
again falls to its former level. During the period 
in which the flood-gates are closed, it is obvious 
that whatever water may accumulate in the ditches 
by rains or other causes, must be removed by me¬ 
chanical means. This may be done in various 
