[Illustration: FIG. 1092.--The Collegiate Church of Rosslyn. Details of Corbels.] of the choir (see Fig. 1084) is built with a curved outline on top, which seems to indicate the form of an intended barrel vault. The gable has been left unfinished, and the existing belfry is obviously a late addition. The above curve, if completed, would comprise the full width of the chapel, embracing both the centre aisle and the side aisles, and would rise considerably above the apex of the roof. The space included between the curves is about 36 feet wide, which is a wider span than would likely be undertaken at this period. The curved form of the top of the west wall of the choir may, therefore, be dismissed as an indication of a probable vault. Attention has already been drawn to the usual mode of finishing the barrel vaults of churches at this period (see _ante_, page 3), viz., by the introduction of four solid walls (with small apertures) at the four sides of the crossing on which the barrel vaults of the various arms of the churches were stopped. This system has, so far as the structure is completed, been adopted at Rosslyn, the wall on the east side of the crossing [Illustration: FIG. 1093.--The Collegiate Church of Rosslyn. Details.] being built so as to receive the barrel vault of the choir. There seems to be no reason why the same plan should not have been intended to be used for the completion of the other sides of the crossing. The edifice would then be in harmony with the other collegiate churches of the period, and may have been intended to be completed with a central tower. The building shown by dotted lines at the west end is a vestry and organ chamber erected a few years ago. The sculpture with which the chapel is so profusely adorned generally represents Scriptural scenes, and has been very minutely described by the Rev. Mr. Thompson in his _Guide to Rosslyn Chapel_. One of the most unique examples amongst the remarkable decorations of the edifice is the ornamentation of the south pillar of the east aisle, [Illustration: FIG. 1094.--The Collegiate Church of Rosslyn. Carved Slab over Entrance to Vault.] generally known as the “’Prentice Pillar” (see Fig. 1081). It consists of a series of wreaths twisted round the shaft, each wreath curving from base to capital round one quarter of the pillar. The ornamentation of the wreaths corresponds in character with the other carving of the church; and the grotesque animals on the base find a counterpart in those of the chapter house pillar at Glasgow Cathedral. Beneath the choir are the vaults in which many of the St. Clairs are buried. The entrance is under a slab on which the incised outline of a knight in armour is carved (Fig. 1094), with a dog at his feet, and a small shield at his head, bearing a lion rampant contourné. [Illustration: FIG. 1095.--The Collegiate Church of Rosslyn. Monument to George, Fourth Earl of Caithness.]