The upper chapel is one of those buildings which one never tires of admiring. When we wend our way up the turret stairs, and enter it from the semi-darkness of the crypt, it strikes us as the most exquisite scheme of colour imaginable. Add to the beauty of the chapel all the associations which crowd upon the memory--S. Louis' beautiful faith and noble life, his enthusiasm for God's work and man's welfare; all the ceremonies and the processions which have taken place there, with the lights, the flowers, and the incense, and our imagination forms a picture that no hand could adequately paint. The chapel is composed of four bays for the nave, and seven smaller for the apse. The vault is groined and is supported by clustered columns and capitals ornamented with foliage. The windows occupy the entire space between the supporting pillars, and are filled with most beautiful stained glass;[7] while below is an arcade rising from a stone seat. The capitals of the columns are most exquisitely carved in imitation of the flora of France, and the quatrefoils between the arches are filled with a kind of decoration which is as rare as it is effective. The designs were drawn upon the stone, and the backgrounds filled in with incrustations of blue glass and gold, the subjects being taken from the lives of the martyrs. Most of them have been restored; but, very wisely, two or three have been left in the state in which they were discovered. Between the arches of the arcades are Angels with outstretched arms, who seem to be crowning the martyrs in the quatrefoils. At the third bay of the nave on each side are recesses which formed reserved places for some privileged persons during Mass; and it is thought that they were probably occupied by the king and queen, the former on the Gospel, the latter on the Epistle side. On the south wall is a slanting recess, which formerly must have served as a chapel, as there was an altar at the end of it having a painted reredos representing the interior of the great _châsse_, with all its contents ranged in proper order, and S. Louis praying before it. It is supposed that Louis XI. may have used this niche as a place where he could pray without being seen, but in sight of the altar and the relics.