Geoscience Reference
In-Depth Information
bile, yellow bile, phlegm, and blood, the four elements water,
re, earth and air, but
also seasons, organs, celestial bodies and more. Paired qualities (cold/hot and wet/
dry) were associated with each humor. Imbalances between the qualities were
conceived as the reason for illnesses and moodiness in humans, but also for the lack
of fertility of a soil leading to dietary recommendations, cures of ailments and to
prescriptions of manures aimed at re-establishing the balance in the soil. Therefore,
many agricultural recipes talk about situations where something is too cold, too hot,
or too dry or wet. While some of these qualities correspond with physically mea-
sureable parameters of soils, not all do. While this theory has long been discarded, it
lead to an astoundingly systematic discussion of soils in the agricultural literature.
The lesser-known Geoponika can serve as an example of the typical knowledge
about manures: Its twenty-
Manure makes good land
better, and it will be of greater service to that which is bad; but that which is
naturally good does not want much manure; that which is of a middling quality, a
little more; and that which is thin and weak, a great deal
rst chapter concerns manure:
“
.
68
We further read that
manure should be dispersed, as an over-abundance causes scorching. Unmanured
land becomes stiff. Compost should not be thrown directly on the roots, but packed
between two layers of earth. This will prevent the burning of the roots and, by
covering the compost, prevent its heat from evaporating. Heat, one of the qualities
discerned in humor theory, can be interpreted in modern terms as the energy
contained in the molecules of fertilizing agents such as nitrates, which would indeed
be better preserved under a protective layer of earth. Bird droppings, with the
exception of that of water birds, are useful, because of their moisture. Pigeon dung
is superior; therefore it is sometimes mixed with the seed when planted, without
further preparation. In addition to rendering an impotent soil more powerful, pigeon
dung can also eradicate agrostis, a grassy weed, which is mentioned throughout the
work. The high appreciation of pigeon dung is shared by Latin writers and the
Ancient Egyptians, but without the explanation that its value is in the moisture it
brings. In fact, bird droppings are a good fertilizer because of their relatively high
phosphorus content.
Like most other agricultural manuals, the Geoponika ranks manures according to
their quality. Next to pigeons, human feces is listed, because it is destructive to
weeds. Human feces, so we are told, is prepared in Arabia by drying it, then
macerating it in water, and drying it again. This manure is used particularly for
vines. Third best is donkey
”
s dung, very fertile and of good use for any plant. Goat
dung, ranked thereafter, is more pungent than sheep
'
s dung, which comes next,
followed by ox dung. Hogs dung is superior in quality, but by its instant heat burns
grain
'
elds, and hence is of no use for them. Horse and mule dung is inferior, but
can be made useful by mixing it with other sorts. The ranking differs from that of
Columella in valuing goat
'
'
s droppings higher than cattle excreta.
Compost (that is, manure made from dung) should never be used fresh, as this will
create many noxious animals (worms). The author(s) think that 3
s and sheep
-
4 year old
68
Owen (
1806b
).
