Gaio Plinio Secondo (il Vecchio), Naturalis historia, libro XXXV, capitolo XLIII, Johannes de Spira, Venezia, 1469

Enough and more than enough has now been said about painting. It may be suitable to append to these remarks something about the plastic art. It was through the service of that same earth that modelling portraits from clay was first invented by Butades, a potter of Sicyon, at Corinth. He did this owing to his daughter, who was in love with a young man; and she, when he was going abroad, drew in outline on the wall the shadow of his face thrown by a lamp. Her father pressed clay on this and made a relief, which he hardened by exposure to fire with the rest of his pottery; and it is said that this likeness was preserved in the Shrine of the Nymphs until the destruction of Corinth by Mummius. Some authorities state that the plastic art was first invented by Rhoecus and Theodorus at Samos, long before the expulsion of the Bacchiadae from Corinth, but that when Damaratus, who in Etruria became the father of Tarquin king of the Roman people, was banished from the same city, [578 B.C.] he was accompanied by the modellers Euchir, Diopus and Eugrammus, and they introduced modelling to Italy. The method of adding red earth to the material or else modelling out of red chalk, was an invention of Butades, and he first placed masks as fronts to the outer gutter-tiles on roofs; these at the first stage he called prostypa, but afterwards he likewise made eciypa. It was from these that the ornaments on the pediments of temples originated. Because of Butades modellers get their Greek name of piastae.