The cathedral, founded about 1150, and added to at various periods, was originally a cruciform structure, consisting of a five-bayed nave with two aisles, late First Pointed mixed with Second Pointed; a transept formed by an extension of these aisles to the north and south; an aisleless choir (with lancet windows), the ruins of which are a fine example of First Pointed work,[150] and which when complete must have been a very pure and beautiful piece of architecture. The north-west tower was being constructed in the time of Bishop Patrick (1351-1373), but must have been a long time in erection. The western doorway presents the oldest feature of the existing building,[151] and is simple and massive. The tower and spire are pronounced to be the completest and best remaining example of their kind in Scotland.[152] By the alteration of 1806 the choir was reduced, the transepts demolished, new and wider aisles built on each side of the nave, while the outer walls of the aisles were carried to such a height that the whole nave could be covered with a roof of one span, "thus totally eclipsing the beautiful windows in the nave, and covering up the handsome carved cornice of the nail-head quatrefoil description which ran under the eaves of the nave."[153] The cathedral was thus sadly deformed, but plans of restoration have been recently adopted, funds are being raised, and the noble minster will before long be restored to its former grandeur. The diocese contained thirty parishes, and the bishop sat in the chapter as Rector of Brechin, that being his prebend.[154] The Maison Dieu formed part of a hospital, and is an interesting part of First Pointed work. The rector of the Grammar School is still "Praeceptor Domus Dei." 7. DIOCESE OF DUNBLANE