What we desire to insist on is not that good architecture is incompatible with structures roofed with timber, or any other material, but that the fundamental principles of Gothic spring from the development of an arcuated style, and that that principle has been only fully and logically carried out in Northern France. In other countries in which Gothic architecture was adopted, much of its spirit was caught and developed; but when the vaulting or dominating feature of the style was absent, the manifestations of the Gothic spirit were comparatively weak and imperfect. These weaknesses and imperfections appear to prove the derivative nature of the architecture in those countries, and especially in Scotland. But the fact of the Gothic of Scotland being of borrowed origin does not prevent much of it here, as in England, from being beautiful and instructive, as, it is hoped, the following pages will show. Probably one of the Scottish edifices in which Gothic principles are best exemplified is Melrose Abbey. The whole building was vaulted with stone, and the vaulting was chiefly groined. The ribs (see Fig. 767) descend on the caps of vaulting shafts of trefoil section, the central division of which rests on a corbel at the level of the main pier caps, while the other two divisions of the trefoil shaft descend without interruption to the base of the piers. That at least was the design, although it was in some of the piers interfered with by the introduction of a screen. In the south aisle also the vaulting ribs are carried on wall shafts or responds, which descend to the bases; but there is an unnecessary amount of wall on each side of these shafts and over the longitudinal arches, which lead into the outer chapels. The vaults are counterpoised with suitable flying arches (see Fig. 766) abutting on solid buttresses, loaded with lofty pinnacles, which give them due resistance to the thrusts brought to bear on them. The windows in the south chapel walls (and clerestory of choir) are larger than usual, and are filled with tracery; but there is here also an unnecessary amount of plain wall between the bays, especially in the nave clerestory. There is, however, at Melrose an entire absence of the heavy blank wall so often introduced over the main arcade, although the absence of any triforium makes the building seem somewhat low and squat. The large amount of solid masonry over the exterior of the great east window of the choir and south window of the transept is likewise a defect. The round abacus is almost always used at Melrose, but the shafts of the piers are simple and distinct, and each member carries a clearly defined series of mouldings.