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34
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DE NATURA FOSSILIUM
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from
its purity, we call "unadulterated" because it is not mixed since
merchants are accustomed to mix it with other inferior earths.
Painters use all varieties of ocher. Artisans use those from Egypt and
Africa, according to Pliny, and physicians that from Sinope. There are
three varieties of this earth, one that is soft and when touched comes
off on the hands and soils them, an intermediate variety which soils
the hands to a lesser extent, and a hard variety which does not soil
the hands unless moistened. Each of these, when moistened, makes an
excellent line and is widely used by artisans. From these properties we
know this genus of ocher to be moderately unctuous, acrid, sometimes
hard, sometimes soft. The loose textured varieties may be either hard
or soft and usually are astringent. Some ochers are not unctuous, for
example that found in Lydia and in part of Hildesheim. The latter
occurs in lumps and has a good red color and good taste. It will adhere
readily to the tongue and then melt like butter. The ocher from Sinope,
according to Dioscorides and Strabo, is obtained from a cave in
Cappadocia and after being cleaned is brought to Sinope, a town in
Pontus, and sold there. The best quality is dense, heavy, and uniformly
liver-colored but this is adulterated and sent to all parts of the
world in large quantities. Strabo writes that a red earth similar in
quality to Sinopian ocher came from Spain. An astringent, white to
reddish-white earth with properties similar to Lemnia earth is found in
Elbogan near the town of Toterbisa and in Hesse between Marburg and
Suenisburg. It is not to be wondered at that there are as many
varieties of red earth as there are of white and other earths.
Armenia
earth which both Paulus Aegineta and Aetius Amidenus call "Armenia
Soil" derives its name from Armenia on the border of Cappadocia where
it is found. This name is also used by the Arabs. It is pale colored
and denser and heavier than Samian aster. It has the appearance
of a stone, yet is soft and friable. Since it dries so excessively it
cures colic and oral ulcers, stops vomiting and bleeding, and reduces
inflammation. It is very useful in treating cases of wasting diseases
and plagues. Paulus Aegineta says it has properties similar to those of
Alana earth.11
A
yellow earth is found in many parts of Germany but is most abundant in
distinctive veins in Bohemia and Hesse near Francoberg. The Hessians
use it to tint leather while the Bohemians and Misenians use it as a
pigment. Although it is highly astringent the Germans usually call
this earth and true ocher by the same name.
Many
earths that are extremely acrid are found in mines and since these have
been dried by the heat of the earth they have the appearance of having
been burnt. They vary in color as much as other earths but in general
are either yellow, tawny, red, or purple. All have the property of
healing and reducing swellings. They all lack names except ocher which
the Latins could have named lutea (clay) if the Greek or foreign term sil
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11 Agricola also calls this earth gelerbolus.
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