CHENTICAL REPORT.



2433 and 2435 are remarkable for their large proportions of
organic and volatile matters, alumina, etc., etc., and especially of
carbonate of lime, TNto. 2435 containing as much as 25.245 per
cent. of that ingredient, constituting it a kind of marl, and No.
2433 contains 4.695 per cent. more than has been observed in
any other Kentucky soil heretofore analyzed. Their propor-
tions of potash, extracted by acids, is also exceptionally large, be-
ing 2.0I5 per cent. in No. 2433 and I.772 per cent. in No. 2435.
They also contain much less than the usual quantity of sand
and insoluble silicates, these being in the proportion of 6i.045
per cent. in the former and only 47.295 in the latter soil. The
former contains 8.2 per cent. of fragments of calcareous fossils
and rock fragments, and the latter, which is a subsoil, as much
as 41.2 per cent., and should be discounted in these proportions.
  A certain small quantity of lime in the soil is essential to pro-
ductiveness, as this substance is an indispensable element of all
vegetable structures, and the influence of very large proportions
of carbonate of lime on the soil has been ascertained to a cer-
tain extent by practical experiment and observation.
  Applied in quantity to a heavy, wet, clay soil, lime, which
soon becomes carbonate, makes it more light and friable, lessens
its tendency to shrink and swell in dry and wet seasons, and
allows water to evaporate from it more freely. But when the
carbonate of lime is in too large proportion, untempered by clay,
it forms a soil which parts with its water too readily, and be-
comes so light in times of drought that its surface may be blown
away by the wind, conditions unfavorable to vegetation. The
chemical relations of carbonate of lime are quite important. In
contact with the insoluble silicates of the soil, it favors their de-
composition, setting free, in a soluble form, their potash, soda,
phosphoric acid, etc. It also greatly aids the decomposition, in
the moist soil, of the organic matters present, causing the more
rapid formation of carbonic acid and water and favoring the pro-
duction of ammonia and nitrates-all essential food of plants.
It also has the valuable property of absorbing and holding for
the nourishment of vegetation, organic matters, ammonia, and
other nitrogen compounds, and the phosphoric acid, which may
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