It may not be often possible to trace as clearly as we have just done in a single instance, the logical order and dependence of the several subjects that were selected for representation in each chamber of the Catacombs; they may not always have been so admirably arranged as to be in fact equivalent, as these were, to a well-ordered dogmatic discourse. Nevertheless it is only when read in this way, that the decoration of the Catacombs can be made thoroughly intelligible; and it is certain that some such meaning must have been intended from the first. The extremely limited number of Biblical subjects selected for representation, while such an immense variety is really contained in the Bible (and so many of those that are neglected might have seemed equally suitable for the purpose), and then again, the thoroughly unhistorical way in which these few subjects are dealt with, shows clearly that the principle of selection was theological rather than artistic. The artists were not left to indulge their own unfettered fancy, but worked under ecclesiastical supervision; and the Bible stories which they depicted were not represented according to their historical verity, because they were not intended to be a souvenir of past facts, but to symbolise and suggest something beyond themselves. In order, therefore, to understand them, it is necessary to bring them face to face with the Christian doctrines which they foreshadow. [Illustration: _Noe in the Ark._] Look, for example, at the numerous pictures of Noe in the ark which appear in the Catacombs, all resembling one another, but none resembling the reality. Instead of a vessel, three stories high, containing eight human beings and specimens of every kind of animal, we see only a narrow box, barely large enough to hold one person, and that person sometimes a lady, whose name is also inscribed upon it perhaps, being the same lady (as we learn from the inscription) who lies buried in the adjacent tomb. If all ancient Christian literature had perished, we should have been at a loss to comprehend this enigma; but as soon as we know that the Fathers of the Church speak of it as an acknowledged fact, which “nobody doubts” (to use St. Augustine’s words), that the Church was typified by the ark, a ray of light begins to dawn upon us; and when we call to mind that St. Peter himself speaks of the waters of baptism as saving men’s souls, “even as Noe and his family were saved by the waters of the flood,” all is at once made clear. We see plainly that the friends of the deceased have intended to signify that he had been received into the ark of the Church and made a Christian by baptism. And if they had added to the composition, as they often did, the figure of a dove bringing an olive branch to the person standing in the ark, this also enters into the same interpretation; it was symbolical of that Divine peace which comes to the soul in this world by faith, and which is a pledge of the peace given by