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Book II About different applications of earths (painting, medical) and their occurrences

Book II About different applications of earths (painting, medical) and their occurrences Page of 251 Book II About different applications of earths (painting, medical) and their occurrences Text size:minus plus Restore normal size   Mail page  Print this page
BOOK II
27
Italy; and the dolia from the island of Ischia which is also called Pithecusa by the Greeks. The pottery of Pergamon and Tralles has added to the fame of Asia. The pottery from Cos was well known to the ancients and that from Samos has been described repeatedly. The exquisite pottery of Aretina and many other localities in Italy and Persia is still being made today. The vessels made at Askalon are highly prized in Syria. The Greeks brought utensils from Keft, Egypt, that had been mixed with scent and resembled the pottery from Rhodes. They called this pottery "aromatic." The Waldenburg pottery easily holds first place as regards usefulness although it is not beautiful while that from Seburg is second. Neither absorbs liquids. Norinberg produces earthenware furnaces used in refining metals and ores. The crucibles used in making brass are made from a clay found near Roteberg, a fortified city twelve miles from Norinberg. When these crucibles, filled with brass, are withdrawn from the furnace they do not break but can be drawn out and twisted like glass. The triangular crucibles used by the men who coin money come from Ipsa, a town of Upper Pannonia. These are made from the Tasconia clay, in Spain. This clay, according to Pliny, is white and resembles argilla. The crucibles can­not be used a second time.
Among the men who work with clay are those who make bricks. They use unctuous, porous clays since these are more coherent and lighter. Al­though they use clay of any color they prefer that which is either white or red. Plasterers use only those clays which are unctuous. The men, called fornacei, who build furnaces and furnace walls prefer an unctuous earth since, according to Pliny, the furnace walls are constructed by tamping earth between two boards instead of building them. If different kinds of earths are available, when constructing high furnaces, heavy earths are placed in the lower portion of the walls, intermediate earths in the middle and light earths at the top. A high furnace of this type can be seen today near Ceruecia, Saxony, and many were built in Spain according to Pliny. Hannibal mentions having seen earthen observation towers that were located on the highest peaks of the mountains in Spain. This class of edifice, although less attractive than one of wood or stone, is more resist­ant to fire, rain, or wind. Earth tremors damage stone towers more than earthen ones. Rains may destroy wooden and even rough stone towers while earthen towers are little affected, if at all. Winds may blow down wooden and even stone structures while those built of earth are more resistant. For this reason Pliny writes that in Africa and Spain walls made of earth resist fire, wind and rain and last forever, actually becoming more resistant with age. In Thuringia and Saxony they mix hair with the clay, as a rule, and construct walls without first tamping the clay into bricks. Such a wall can be seen today at Cribera, Misena, about five miles from Leipzig.
I shall now take up fuller's earths which are unctuous but, having been dried over a fire, become acrid and, because of this, possess the power to
Book II About different applications of earths (painting, medical) and their occurrences Page of 251 Book II About different applications of earths (painting, medical) and their occurrences
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