_St. Peter’s Chapel, &c._--To the east there were some detached buildings, at least in later times. The Anonymous we have seen mentions a chapel of St. Peter as near the skeuophylakium. Anthony speaks of this chapel, in which St. Peter’s chains and the carpet of St. Nicholas were preserved, as behind the altar. The anonymous Russian says a chapel of St. Nicholas was behind the bema, and also speaks of a marble basin covered with a lead roof, “where they baptise the emperors” as being behind the altar, in a space set round with cypresses. Anna Comnena also mentions “the chapel of the Hierarch Nicholas” as part of the Great Church and a place of sanctuary.[305] The passage of St. Nicholas is also referred to. It is possible that this chapel was otherwise known as St. Peter’s, and either this or “the place where they baptise the emperors” may be the present round building--the ancient baptistery as we suppose. That St. Peter’s chapel was of some importance and detached seems clear from the _Menologium_. On January 16 was celebrated the adoration of St. Peter’s chains. It is explained that after Peter’s release, “the chains were found by some believers and guarded from generation to generation until they were brought to Constantinople by a pious emperor and placed in the church (ναὸς) of St. Peter which is near St. Sophia.” We have given a picture of the chains in Figure 8. A tradition of some of these buildings may be preserved in an Italian MS. of 1611 in the British Museum. “The ancient buildings round the church have been ruined by the Turks except a small part of the close (_canonica_), where they have made dwellings; there is also the sacristy and the place of the baptistery, which had originally three vaulted ceilings, one above another. It was of wonderful architecture and made with six angles. From the sacristy to the base of the dome is an arquebus shot; between it and the Seraglio lies a road.”