Notwithstanding the beauty of many of our larger and finer edifices, such as Holyrood and Melrose Abbeys, and Glasgow, Dunblane, and Elgin Cathedrals, evidence is wanting in the design of these edifices of a full appreciation of the leading principles which inspired and guided the architects of the Ile de France. The Scottish buildings represent the echo rather than the original voice of the genius of Gothic architecture. The principal aim of the French architects of the latter half of the twelfth century and during the thirteenth century was to produce structures in which the arcuated or vaulted system of building should be developed to its fullest extent. With these architects the vaulted construction of the roof thus became the ruling element in the design, all the other features being wrought out so as to be supplementary to, and indicative of, the principles of the arcuated style. Every detail was designed so as to fulfil its structural function in subordination to that general idea. Thus the ribs of the vaults formed the framework on which the vaulting panels rested, and conveyed the pressures created by the weight of the roof to the points where these pressures were all concentrated on the capitals of the wall shafts. From that point the forces so concentrated were distributed, the vertical pressure being conveyed downwards by the wall shafts to the foundations, and the horizontal thrusts being counterbalanced by buttresses and flying buttresses, which performed their share of the work by carrying these forces obliquely to the ground. These primary features were the skeleton which constituted the main elements of the building. They formed a structure in stable equilibrium, which was independent of the filling in of the walls, with windows, doors, and other details. The latter were but the clothing and ornamentation of the main structural framework, and in the completed style (as at Amiens Cathedral), all superfluous masonry is abolished, and the spaces between the main structural elements are enclosed with screens of tracery. The Gothic structure was thus a composition in complete contrast with the Romanesque or Norman edifices which preceded it. In the latter, although arching and even vaulting were employed, the arched system of construction was in an elementary state, and the inert mass of the walls was chiefly relied on as a counterpoise to the thrusts of the arches.