In other words, if all the particles in one cubic inch of soil
consisting of fine silt were placed side by side, they would form a
continuous chain over a thousand miles long. The farmer, when he
tills the soil, deals with countless numbers of individual soil
grains, far surpassing the understanding of the human mind. It is
the immense number of constituent soil particles that gives to the
soil many of its most valuable properties.
It must be remembered that no natural soil is made up of particles
all of which are of the same size; all sizes, from the coarsest sand
to the finest clay, are usually present. These particles of all
sizes are not arranged in the soil in a regular, orderly way; they
are not placed side by side with geometrical regularity; they are
rather jumbled together in every possible way. The larger sand
grains touch and form comparatively large interstitial spaces into
which the finer silt and clay grains filter. Then, again, the clay
particles, which have cementing properties, bind, as it were, one
particle to another. A sand grain may have attached to it hundreds,
or it may be thousands, of the smaller silt grains; or a regiment of
smaller soil grains may themselves be clustered into one large grain
by cementing power of the clay.
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