Dryden’s conjecture that the church of Egilshay was built by Norsemen after the Irish model shortly after the reconversion of the Islands to Christianity _c._ 998 A.D., is a view which presents no anomalies either architectural or historical, when we consider that at that date many early Celtic churches must have survived in Orkney, and that, in any case, the close connection between Norse Orkney and the Scandinavian colonies in Ireland would give Orcadians ready access to Irish models. The alleged dedication of this church to St Magnus rests on the late and doubtful authority of Jo Ben (1529), but it was no doubt popularly associated with the Saint’s name because, as the _Orkneyinga Saga_ tells, he entered it to pay his devotions on the day of his murder. [Illustration: Apse of ancient Round Church, in Orphir] In the parish of Orphir, contiguous to the present parish church, stands the only example in Scotland of a circular church, built in imitation of the church of the Holy Sepulchre at Jerusalem. All that remains of this interesting building, however, is the semicircular chancel, which is 7 feet 2 inches wide and 7 feet 9 inches deep, and about 9 feet of the circular nave on either side. From the curvature of the remaining portion, the diameter of the nave must have been from 18 to 19 feet. Dryden conjectures that the side walls of the nave may have been 15 feet or more in height, and that they were surmounted by a conical roof. This church was almost to a certainty erected by Jarl Hakon, the murderer of St Magnus, after his return from his expiatory pilgrimage to the Holy Land _c._ 1120. 16. Architecture—(_b_) Castellated The early Norsemen in Orkney built their houses of wood imported from Norway, with only a slight foundation of stone; and the Norse theory of defence lay in attacking the foe, preferably on sea. Save, therefore, for a few buildings erected by Jarl or Bishop, and by one or two powerful Viking chiefs, stone masonry during the purely Norse period (870-1231) was practically confined to churches. Even during the Scoto-Norse (1231-1468) and Scottish periods men of sufficient power and wealth to erect imposing buildings of stone were still few. Compared, therefore, with an ordinary Scottish county the castellated architecture of the Islands is meagre in quantity; but several of the buildings of this class that remain are of exceptional interest and beauty. [Illustration: Noltland Castle, Westray (15th century)] [Illustration: The Staircase, Noltland Castle]