more true, and ‘the well may still be seen’ behind the altar of the Virgin. CRYPT: NOTRE-DAME-DE-SOUS-TERRE. The oldest portions of the crypt, and therefore of the Cathedral, that remain to us are to be found in the Martyrium or Chapel of S. Lubin. The crypt, it must be understood, was not in origin a crypt or a martyrium or a meeting-house of prayer dug beneath the level of the soil, but a tiny church set on the crest of the hill, and raised above the surface of the earth. It only became a crypt properly so-called when it had been covered up and the surrounding soil raised by the _débris_ and deposits of succeeding years; so that when the new church was built it was erected naturally upon the top of the old. The spade of the archæologist has proved that the soil of a mediæval European town was raised by the accumulation of dust and rubble as much as one or two feet per century. And at Chartres excavations have revealed Gallo-Roman sub-structures at a depth of some eighteen feet. When we reach the Martyrium or Chapel of S. Lubin we shall find there a piece of the Gallo-Roman walls of the fourth century. This probably is part of the apsidal wall of the church of that date. As the church, with the vicissitudes of the town which we have yet to recount, was alternately built and burnt, destroyed and rebuilt, the crypt was developed until it is now the largest in France, and next to that of S. Peter’s at Rome, and that of Canterbury, the largest in the world. It consists of two lateral galleries which run from the western towers under the aisles of the upper church, and form a horse-shoe curve beneath the choir and sanctuary 366 feet long, and seventeen to eighteen feet broad; of two transepts, seven apsidal chapels, and the _martyrium_ which is under the choir of the upper church. The successive developments of the crypt may be summarised as follows:--