Very important works in ivory were executed in the time of the Roman Empire, in the nature of “Consulare” diptychs and triptychs. These Consular diptychs were originally made of wood or ivory, and were hinged tablets that folded over each other, the outside surfaces being carved elaborately, with a portrait or figure of the Consul or chief magistrate of the province in the centre, the inside surfaces being used for writing purposes. These consulares were also called “pugillares” from being portable objects that could be carried conveniently in the hand or _fist_. They were usually made as presents to be given to important people of distant provinces, or to very intimate friends of the Consuls. After the adoption of the Christian religion by the Roman Empire it was the custom of the Consuls to send these consulares in the form of a diptych or triptych, as a present to the bishop of a church in his province, to show his patronage and goodwill, and they were usually placed on the altar of the church, in order that the congregation should see them and remember the giver in their prayers. This custom led to the making of the diptychs (_two-leaved_) and the triptychs (_three-leaved_), for the purpose of the altar decorations, and usually on the plain inner leaves were inscribed the names of the newly baptized (_neophytes_) Christians, benefactors to the church, dignitaries of the same, and Christian martyrs. The use of these led to the later magnificent painted and carved altars of the triptych order in Christian churches. During the persecution by the iconoclastic Emperors of the Eastern Empire a great number of these triptychs were made in wood and in ivory of Greek workmanship, carved or painted on the interior faces with representations of saints and sacred personages. These were used as portable altars, and were carried about the person of those who used to pray before them in secret. Many of them were also of a good size, and became later important objects that were placed above or near the “prie-dieus” in private rooms or chapels. The smaller pugillares, and larger ecclesiastical diptychs were used in later times to form the coverings of costly illuminated books, and it is owing to this use of them that so many have been preserved to our day. Byzantine sculpture and ivory carvings of the eleventh and twelfth centuries were invested with the same severe and solemn character that was the distinguishing feature of the ceiling and wall mosaics of the same period. The figures were long and attenuated, the draperies very stiff and angular and arranged in parallel folds, which, with the German phase of Christian art, developed later into a still more angular and rocky character. In France, on the other hand, in the thirteenth century there arose a splendid and original school of sculpture, entirely native, whose richest efforts culminated in such masterly achievements as the figure sculpture of the cathedrals of Rheims, Chartres, and Amiens.