All these proportions are somewhat flexible, inasmuch as they may include the side walls and exclude the end walls, or the reverse; or they may include both, or they may exclude both; or they may be applied in one way to the nave, and in another to the chancel, and in another to the tower. But the proportion must not be deemed as ascertained unless the figure really fits within 2 or 3 inches. DATES. As to the dates of these buildings we have but little to guide us. Only fragments of the buildings are left, and those of the plainest description. Scotch architecture has some mystifying peculiarities. Dates have been suggested from architectural and historical evidence for Orphir, Birsay, and Egilsey. Orphir, 1090-1160; Birsay, 1100; Egilsey, 1000. Wyre has been assigned to the twelfth or thirteenth, the Ness to the fourteenth, and St. Ola to the sixteenth century. It may be fairly observed that there must have been churches erected in the fourteenth and fifteenth centuries. Where are the remains of them? Possibly some of the ruins described are of those centuries. It does not appear impossible that from evidence yet to be collected, a nearer approximation to the dates of these buildings may be got. * * * * * As a supplement to the foregoing drawings and descriptions of the ruined churches of Orkney and Shetland by Sir Henry Dryden, we add an account, also kindly supplied by Sir Henry, of the chapel at Lybster, in Caithness, which has a strong affinity to the churches of the Orkneys, and drawings and description of the chapel on the island of Inch Kenneth, lying on the south-west of Mull. CHAPEL AT LYBSTER, PARISH OF REAY, CAITHNESS. This is not the Lybster on the east coast. This chapel (Fig. 129) was stated, in 1726, to be dedicated to St. Peter. It is described and illustrated by Muir in his _Ecclesiastical Sketch of Caithness and Orkney_, 1861. He states that it was dedicated to St. Mary.[135] It consists of nave and chancel, both unroofed. (Fig. 130.) Muir, in his plan, places the chancel to the north of the nave, but it is in the usual position. The nave is 17 feet 10 inches east and west, by 10 feet 11 inches north and south inside. The north wall of the nave is 3 degrees south of true west and north of true east, supposing the variation to be 24 degrees west of north. The walls of the west end and the east end of the nave are 4 feet 2 inches thick; the north and south walls of the nave are 3 feet 11 inches thick. The walls are of the whinstone of the district, in irregular courses, from 3 to 10 inches deep, and “spawled”--that is, made into courses by smaller stones. The north wall of the nave is 8 feet high above the present ground level, and is apparently about its original height. The south wall is partly broken. The west wall is 11 feet 8 [Illustration: FIG. 129.--Chapel at Lybster. View from South-West.] [Illustration: FIG. 130.--Chapel at Lybster. Plan, South Elevation and Section.]