Elaboration and simplicity were both so well known to the Gothic architect that it is difficult to say that either of these qualities belongs exclusively to his work. But he was rarely simple when he had the opportunity of being elaborate, and simplicity was perhaps rather forced upon him by the circumstances under which he worked, by rude materials, scanty funds, and lack of skilled workmen, than freely chosen. Many of the great works of the Gothic period are as elaborate as they could be made (Fig. 60), and yet, when simplicity had to be the order of the day, no architecture has lent it such a grace as Gothic. The last pair of qualities is similarity and contrast. What has been said about repetition has anticipated the remarks called for by these qualities, so far as to point out that even where the arrangement of the building dictated the repetition of similar features, a general resemblance, and not an exact similarity, was considered sufficient. In the composition of masses of building, contrast and not similarity was the ruling principle. Even in the interiors of great churches which, as a rule, are far more regular than the exteriors, the contrast between the comparative plainness of the nave and the richness of the choir was an essential element of design. External design in Gothic buildings depends almost entirely upon contrast for its power of charming the eye, and it is this circumstance which has left the successive generations of men who toiled at our great Gothic cathedrals so free to follow the bent of their own taste in their additions, rather than that of their forerunners. But setting aside the irregularities due to the caprice of various builders, and the constant changes which took place in detail through the Gothic period, it is to contrast that we must trace most of the surprising effects attained by the architecture of the Middle Ages. The rich tracery was made richer by contrast with plain walls, the loftiest towers appeared higher from their contrast with the long level lines of roofs and parapets. It is, in truth, one of the principal marks of the decadence which began in the fifteenth century that the principle of contrast was, to a considerable extent, abandoned, at least in the details of the buildings if not in their great masses. Walls were at that time panelled in imitation of the tracery of the adjoining windows, and no longer acted as a foil to them by their solid plainness; long rows of pinnacles, all exactly alike, followed the line of the parapets, and a repetition of absolutely identical features became the rule for the first time in the history of Gothic art. There can be no doubt that had this modification run its natural course unchecked and undisturbed by the change in taste which abruptly brought the Gothic period to a close, it must have resulted in the deterioration of the art. [Illustration: {SCULPTURED ORNAMENT FROM RHEIMS CATHEDRAL.}]