Prothyron

PROTHYRON. - A small structure attached to the entrance of a church building, of a quadriportico or of a portico, is called a p.; in its simplest form it consists of a vault supported by two or more piers or columns.

The oldest examples of the p. are found in the Eastern architecture of the first centuries of Christianity. That of the church of Etchmiadzin, consisting of a small tower attached to the facade of the building, dates back to the 5th century. Even the side abutting the facade of the quadriportico of the ancient Vatican Basilica, in the ideal reconstructions that exist of that building, must have had a p. This, in any case, appears in Italy already in the church of the Sts. Martyrs at Cimitile in the 8th century and thereafter spreads widely during the Romanesque period. And this not only in the characteristic and very simple examples of the Roman churches of S. Prassede, S. Maria in Cosmedin, S. Clemente and S. Cosimato, where the p. must truly have had a protective function for those who lingered outside the church, or, when the p. was in two orders, was the place where the guardian who kept watch over the church entrance was stationed, but also in those of northern Italy where, as at Cremona, Piacenza, Modena, Bergamo, Ferrara, Verona, etc., it took on the dignity of a decorative element intended to give impressiveness to the entrance of the building. In this sense, among the most beautiful are that of S. Ciriaco in Ancona, a work of the 13th century, and that of the side door of the parish church of S. Quirico d'Orcia, whose corbels supporting the short vault are to be assigned to the school of Giovanni Pisano. - See plate IV.

Emilio Lavagnino