or CALCEDON, anciently known by the names of Procerastis and Colbysa; a city of Bithynia, situated at the mouth of the Euxine, on the north extremity of the Thracian Bosphorus, over against Byzantium. Pliny, Strabo, and Tacitus, call it, The City of the Blind; alluding to the answer which the Pythian Apollo gave to the founders of Byzantium, who, consulting the oracle relative to a place where to build a city, were directed to choose that spot, which lay opposite "to the habitation of the blind;" that is, as was then understood, to Chalcedon: the Chalcedonians well deserving that epithet for having built their city in a barren and sandy foil, without seeing that advantageous and pleasant spot on the opposite shore, which the Byzantines afterwards chose.—Chalcedon, in the Christian times, became famous on account of the council which was held there against Eutyches. The emperor Valens earled the walls of this city to be levelled with the ground for siding with Procopius, and the materials to be conveyed to Constantinople, where they were employed in building the famous Valentinian aqueduct. Chalcedon is at present a poor place, known to the Greeks by its ancient name, and to the Turks by that of Cadiaci, or, "the judges town."