This article is in four sections. The first, by the Bishop of Gibraltar, describes his original visit to the church and the impression made upon him by its interior. The second, by Major Vivian Seymer, gives an account of the fabric and the main features of its probable history. In the third section Mr. William Buckler catalogues the frescoes, with brief notice of each, and transcribes the inscriptions on them in cases where these seem to be of special interest. Lastly, Mrs. William Buckler states reasons, based on the evidence of the three historical inscriptions, for believing that the church was probably erected in 1106 by Nicephorus, son-in-law of the emperor Alexius Comnenus and brother-in-law of Anna Comnena the historian. The plan and sections are by Major Seymer.