whilst by its variations during successive ages it faithfully reflects (we may be sure) some corresponding change in the tone and temper of the ordinary Christian mind. Christian epigraphy was born as Christian art was, simultaneously with the introduction of Christianity itself into the metropolis of the ancient world; it acquired all its special characteristics, and perhaps attained its highest religious perfection, before the end of the third century, after which its beautiful and touching simplicity is somewhat marred and secularised by a gradual influx of some of those modes of thought and expression which prevailed in the world without. Part Second. CHAPTER I. THE PAPAL CRYPT. We have now acquired a sufficient general idea of the Catacombs to enable us to understand what we see when we come to examine any one of them in detail; and we will, therefore, proceed to pay a visit to the famous Cemetery of Callixtus. But first we must explain what is meant by this title. It may be used in two senses. When first the Catacombs were made, and as long as the true history of their origin and gradual development was remembered, “the Cemetery of Callixtus” was only a small and well-defined area, measuring 250 Roman feet by 100, and situated on a little cross-road which united the Via Appia with the Via Ardeatina. But as time went on, other areæ were joined to this, until at length a vast and intricate subterranean necropolis was formed, measuring several hundred feet both in length and breadth; and to the whole of this space, for convenience’ sake, we continue to give the name of one of its most ancient and famous parts. In our visit we shall pass through some portions of several of these areæ; for we shall first descend into the original “Cemetery of Callixtus,” and we shall return to the upper world from the “Crypt of Lucina,” which in the old martyrologies is spoken of as “near” that cemetery, not as part of it. [Illustration: _Galleries in Cemetery of St. Callixtus breaking through graves._]