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ARSENIC (symbol As, atomic weight 75-0), a chemical element, known to the ancients in the form of its sulphides. Aristotle gave them the name aa.v5apa.Kii, and Theophrastus mentions them under the name apotviKov. The oxide known as white arsenic is mentioned b ...

ARSENIUS (c. 354-450), an anchorite, said to have been born of a noble Roman family, who achieved a high reputation for his knowledge of Greek and Roman literature. He was appointed by Theodosius the Great, tutor of the young princes Arcadius and Honorius, but

ARNICA, a genus of plants belonging to the natural order Compositae, and containing 18 species, mostly north-west American. The most important species is Arnica montana (mountain tobacco), a perennial herb found in upland meadows in northern and central Europe

... has been carefully investigated. In alkaline solution azobenzene results, while arsenic acid produces the violet-colouring matter violaniline. Chromic acid converts it into quinone, while chlorates, in the presence of certain metallic salts (especially of vana ...

... um, and large deposits of salt. In smaller quantities are found zinc, antimony, arsenic, cobalt, nickel, manganese, bismuth, chromium, uranium, tellurium, sulphur, graphite and asphalt. There are also marble, roofing-slate, gypsum, porcelain-earth, potter's cl ...

... ensive, tin, nickel, copper and iron. Gold is found in several places, and some arsenic, antimony, bismuth, manganese, mercury and sulphur. The Erzgebirge is celebrated for its lace manufactures, introduced by Barbara Uttmann in 1541, embroideries, silk-weavin ...

... ble amounts of silver, iron, zinc, mercury, lead or cobalt, and the antimony by arsenic or bismuth. In general, the formula is R'6X2S6-|-*R''eX2S9, where R'=Cu, Ag; X=Sb, As, Bi; R* = Fe, Zn, and x is a small fraction, often ^ or £. Numerous special names have ...

... logical Survey are: natural pigments, felspar, white mica, graphite, fluorspar, arsenic, quartz, barytes, bromine. Some dozens of varieties of precious stones occur widely. Of building-stone, clay, cement, lime, sand and salt, the country's supply was estimate ...