"In considering the system of symbolism it is necessary to study the significance of numbers. The secrets of church building can only be discerned by recognizing the mysterious idea of the unity of the figure I., which is the image of God Himself. The suggestion of II., which figures the two natures of the Son, the two dispensations, and, according to Saint Gregory the Great, the two-fold law of love of God and man. Three is the number of the Persons of the Trinity, and of the theological virtues. Four typifies the cardinal virtues, the four Greater Prophets, the Gospels and the elements. Five is the number of Christ's wounds, and of our senses, whose sins He expiated by a corresponding number of wounds. Six records the days devoted by God to the creation, determines the number of the Commandments promulgated by the Church, and, according to Saint Melito, symbolizes the perfection of the active life. Seven is the sacred number of the Mosaic law; it is the number of the gifts of the Holy Ghost, of the Sacraments, of the words of Jesus on the Cross, of the canonical hours, and of the successive orders of priesthood. Eight, says Saint Ambrose, is the symbol of regeneration, Saint Augustine says of the Resurrection, and it recalls the idea of the eight Beatitudes. Nine is the number of the angelic hierarchy, of the special gifts of the Spirit as enumerated by Saint Paul; and it was at the ninth hour that Christ died. Ten is the number of laws given by Jehovah, the law of fear; but Saint Augustine explains it otherwise, saying that it includes the knowledge of God, since it may be decomposed into three, the symbol of a triune God, and seven, figuring the day of rest after the Creation. Eleven, the same saint explains as an image of transgressing the law and an emblem of sin; and Twelve is the great mystic number, the tale of the patriarchs and the Apostles, of the tribes, the minor prophets, the virtues, the fruits of the Holy Ghost, and the articles of faith embodied in the _Credo_. And this might be repeated to infinity. Hence it is quite evident that the artists of the Middle Ages added to the meaning they assigned to certain creatures and certain things, that of quantity, supporting one by the other, emphasizing or moderating a suggestion by this added-means, working back sometimes on a former idea, and expressing this duplication in a different form or concentrating it in the energetic conciseness of a cipher. They thus produced a whole at once speaking to the eye and, at the same time, giving synthetical expression to the complete text of a dogma in a compact allegory." "But what hermetic concentration!" exclaimed Durtal. "Very true; these various meanings of persons and objects, resulting from numerical differences, are at first very puzzling." "And do you suppose that, on the whole, the height, breadth, and length of a cathedral reveal a specialized idea, a particular purpose on the part of the architect?"