SCULPTURE: TECHNIQUE. Though wood and clay were sometimes used in sculpture, the com mon materials were stone and metal. In the early days of sculpture in stone the softer varie ties of limestone, especially the so-called poros, were frequently employed because of the com parative ease of working. Later the harder marbles were employed. especially the fine white marble of Paros, and Mount Pentelicon, in Attica. The sculptor seems in general to have worked without mechanical copying of a model. For blocking out the statue a pointed instrument, either a punch or hammer, was employed, and the finer details were worked out with chisels of various shapes. In some of the earlier statues the deep folds of drapery seem to have been cut out by the saw; but later the borer was used, especially after the time of Callimachus (q.v.), who is credited with its invention by Pausanias, though it was almost certainly in use at an ear lier date. Frequently the head and other parts
of the body were carved separately, and of bet ter material. In bronze the earliest works are in hammered metal, with engraved details; but at an early date casting was introduced, and thus the production of larger pieces became pos sible. Heretofore such statues had been produced by plating on wood, or riveting together metal plates. Solid casting was obviously too waste ful, and we early find examples of hollow cast ing, though the exact method of preparing the mold and core is uncertain. In later times the Greek artists used the tire perdue process, and it is possible this was in use before the end of the fifth century. Bronze was always the fa vorite material for honorary statues, and the artists in bronze seem to have enjoyed a higher esteem than their brethren who worked in stone.