The cap of the west pier on the north side belongs to the first pointed work, while the corresponding cap on the south side (see Fig. 962) and all the other caps belong to the restoration of the fifteenth century. The above cap and all the later caps in the nave have the upper mouldings run in a straight line without any break, while the lower mouldings break round the section of the piers (Fig. 964).[13] A moulded shaft, considerably off the perpendicular, rises from the top of the above cap to the string course at the junction of the old and the restored wall. The piers of the nave, except the west piers, are of a clustered form not uncommon in late work in Scotland. The caps and main arches have good mouldings, and might be about the date of the restoration of St. Giles’, Edinburgh (which they resemble), in the early part of the fifteenth century. The design of the triforium is very remarkable (see Figs. 961 and 962), consisting of large segmental arches the same width as the main arches, springing from short clustered piers introduced between them. Each arch is filled in with two pointed arches resting on a smaller central shaft. These arches and the spandril between them are treated with bold cusping. The triforium of the nave of Dunkeld Cathedral somewhat resembles that at Paisley Abbey. It contains a series of semicircular openings filled with similar pointed arches and cusping, but the work at Paisley is superior, and would appear to be the earlier of the two. In neither church is there any vaulting shaft to divide the bays. The clerestory is probably designed in imitation of that of Glasgow Cathedral. It is divided into two pointed arches in each bay. These spring from a series of clustered shafts with round moulded caps, which have an early character, but are evidently late imitations of early work. The exterior views (see Figs. 957 and 959) show that each clerestory window contains a central shaft, with two cusped arches and quatrefoil in the arch-head. The parapets of the nave and nave aisles are evidently, from the style of the mouldings and ornaments, of late date. There seems to be no reason to doubt that, as above stated, the upper portions of the nave were carried out about the time of Bishop Tervas, in the middle of the fifteenth century. The earlier part of the restoration, including the main piers and arches, and perhaps the tracery of the two lower windows of the west front, were possibly executed by Bishop [Illustration: FIG. 964.--Paisley Abbey. Pier of Nave.]