valuable part, and that leaching in the barnyard carries away value
more rapidly than decrease in volume of manure indicates. The widely
demonstrated facts do not have effective acceptance, and enormous loss
continues.

Thorne found that manure placed in flat piles in the barnyard in
January, and allowed to lie until April, lost one third of its value.
Under the conditions prevailing on many farms the loss suffered by
exposure of manure is far greater.

[Illustration: Concrete stable floors.]

Caring for Liquid Manure.--If all manure were in solids, one great
difficulty in caring for it would not exist. The nitrogen is the most
valuable element in manure, and two fifths of all of it in horse manure
is found in the liquid. In the case of cow manure, over one half of the
nitrogen is found in the liquid. More than this, a pound of nitrogen in
the liquid has greater value than a pound in the solid because of its
nearly immediate availability. There is only one good way of caring for
the liquids, and that is by use of absorbents on tight floors or in
tight gutters. American farmers find cisterns and similar devices
nuisances. The first consideration is to make the floor water-tight,
and clay will not do this. The virtues of puddled clay have had many
advocates, but examination of clay floors after use will show that
valuable constituents of the manure have been escaping. The soils of
the country cannot afford the loss, and careful farm management
requires acceptance of the truth that a tight floor is as necessary to
the stable as to the granary. The difficulty in supplying a sufficient
amount of absorbents on tight floors only emphasizes the loss where
floors are not water-tight.

Use of Preservatives.--The use of land-plaster in stables helps to
prevent loss of the nitrogen-content through fermentation. Its value
does not lie chiefly in physical action as an absorbent, but the
beneficial results come through chemical action. The volatile part of
the manure is changed into a more stable form. In recent years this
preservative has fallen somewhat into disuse, as acid phosphate
contains like material and also supplies phosphoric acid to the manure.
The phosphoric acid content of stable manure is too low for all soils,
and the reenforcement by means of acid phosphate would be good practice
even if there were no preservative effect. The use of fifty pounds of
acid phosphate to each ton of manure will assist materially in