Throughout the eleventh and twelfth centuries the Norman shield remained with very little modification, and was therefore the first shape to which regular heraldry was applied. The subjects, besides the armorials which were gradually increasing in number and in regularity of arrangement, were at first little more than fanciful decoration, the signs of the zodiac and similar devices, as well as the badges, which long continued to be used from time to time in a more ephemeral way than the regular armorials, though nearly approaching them in character. Very early in the thirteenth century the height of the shield began to decrease, and continued to do so until by the middle of the century an almost equilateral form was arrived at (Figs. 7, 8, 9). This was probably the effect of the progress in the making of defensive armour, whose improvement ultimately resulted in the disuse of the shield altogether. By the end of the thirteenth century heraldry had become general, and the triangular shields bore coats of arms which showed in their composition the influence of the shape that contained them. The fact that a single lion was depicted as rampant rather than in another pose, was probably due at first to the greater ease with which it could thus be adapted to the space and so satisfy the decorative sense of distribution. And the attitude was already in existence in the designs of the textiles and in other works of Eastern origin. [Illustration: FIG. 7.] [Illustration: FIG. 8.] [Illustration: FIG. 9.] Until the beginning of the fourteenth century the curves which describe the sides of the shield commenced quite at the top, but soon afterwards (the shape becoming rather narrower in proportion to the height) the side lines began straightly at right angles with the top and, at about one-fourth of the height, began to develop into the curve which formed the point (Fig. 11). This is known as the heater shape from its resemblance to the heater of a smoothing iron. Soon afterwards the straight part of the sides extended downwards and the shield, thus becoming wider at the base, more nearly approached the square form, as in Fig. 12. The shapes here given are designed to explain the varying forms from time to time, and not the relative size of actual shields. [Illustration: FIG. 10.] [Illustration: FIG. 11.] [Illustration: FIG. 12.]