ught to be admissable to
any extent in pot culture, or in the growth of forced plants, in
preference to a supply of wholesome unexhausted natural soil.

A very great objection to the use of dung when applied in a solid state in
the composition of soils, consists, in its being presented to the roots of
plants, not only in the advanced periods of their existence, but equally
so, during the early stages of their growth; here must be an error, for
infants, whether they belong to the animal or vegetable kingdom, are
certainly not capacitated to appropriate the same kind of food, in the
same proportion, as adults. If only a small portion of soil is at first
employed, and portions more and more enriched, are from time to time
added, as the roots may extend, we are still liable to stumble on an
objection, almost as important, though of a somewhat different nature; for
we can in that case scarcely fail to injure the spongioles of the roots in
a greater or less degree, and the injury thus sustained, will consequently
act as a check in the progress of their developement. These considerations
seem at once to mark the propriety of applying liquid manures in highly
artificial cultivation; they can be supplied in this state, when the
plants are in such a mature and advanced state of growth, as from time to
time to require their aid; and their fertilizing properties being held in
solution by the fluid medium in which they are conveyed, they are just in
the condition to be taken up at once by the rootlets. It must still
however be recollected, that whilst even impalpable powders cannot as such
be made to minister to the nutrition of plants, so neither can gross
liquids effect this purpose: it is clear limpid fluids, only, which can be
received by the delicate spongioles, and therefore the so-called manure
water, when applied of the consistency of mud, is not only in an unfit
state to effect its purpose, except by the addition of a more bountiful
supply of pure liquid, but it is also liable to act injuriously by reason
of the concentration of the strength or powerful qualities of the manure,
and by counteracting the open texture of the soil. Manure water,
therefore, from whatever source it may be derived, though not necessarily
a colourless, should without question, be a limpid fluid; if otherwise
applied, it will at once destroy one of the best qualities a soil can
possess, viz. porosity.

CHAP. VI.

ON THE APPLICATION OF MOISTU