CHEMICAL REPORT.



these objectors is that the acid solvents used by the chemists in
their analyses differ from the natural agents of solution by which
the soil elements are made available for plant growth. But
Liebig himself measurably destroyed the force of this objection
when he called attention to the fact that plants do not derive
their soil ingredients from the so-called " soil water" alone, but
exert, through their rootlets, a direct solvent action on the parti-
cles of the soil; and the solvent is proved to be an acid one.
The present writer, in experiments detailed in a previous report,
proved that strong acids, such as oxalic and phosphoric acids,
enter into the composition of this peculiar solvent or digestive
fluid of plants, by means of which solid ingredients of the soil
are dissolved and made available for their nourishment and
growth.
  Time and experience have gradually set aside most of the
objections which were made to this mode of studying the char-
acter and value of soils, and in a new country no other method
is known by which the capabilities of the virgin soil can be so
cheaply, speedily and certainly estimated.  More especially is
this true in Kentucky, where the soils have mostly been formed
in place by the disintegration of the subjacent rocks, and not of
transported materials.
  We may briefly recapitulate some of the peculiar uses of soil
analysis:
  i. To teach the natural capabilities of the soil; its present
probable fertility and durability under existing conditions.
  2. To detect elements or conditions injurious to plant growth,
and point out available remedies.
  3. To show any surplus or deficiency of essential elements,
and indicate the best remedies-fertilizers or mechanical agencies.
  A good analysis of the soil of a homogeneous field may be
beneficial for ages, if properly understood and judiciously taken
as a guide in culture and the application of fertilizers.
  A good exemplification of these facts appeared in -a letter
from Charles Bernard to the New York Evening Post, in I 87I,
giving an account of the extraordinary farming operations of

   See Vol. V., Ky. Geological Reports, N. S., pp. 239, 244.
   6



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