The tracery in the great windows in the west end (see Fig. 569) and in those of the north transept (see Fig. 593) and south transept is modern, and it is not easy to determine how far the designs follow the originals. The north transept window (see Fig. 596), which was “taken down and rebuilt,”[66] looks, from the simplicity of its design, to be probably like what the original may have been. Regarding the other two great windows, one cannot be so sure. The great buttress enclos- [Illustration: FIG. 595.--St. Mungo’s Cathedral. Window in North Aisle of Choir.] *ing the staircase at the north-west angle of the north transept (see Fig. 596) is a noteworthy feature, differing as it does from the other buttresses flanking the end walls. It occupies part of the space which naturally falls to the eastmost window of the nave aisle, and this opening, instead of being designed as a smaller window to fit the space, is treated with the same design as the others, and thus presents the appearance of having been cut in two. In each of the four great gables the vesica aperture occurs; and this, along with the constant repetition throughout the whole building of certain features, such as the parapets with their supporting corbels, the peculiar gargoyles, the slender buttresses in the clerestories, and the terminations of the main buttresses, all show that the keynote of the design struck by the early builders was taken up and continued by their successors. As above pointed out, this, no doubt, partly arose from the lower portions of the whole structure having been begun at an early period, though, in part, not finished till a later time. Even in the chapter house building (Fig. 597), the upper story of which is of a distinctly Scottish character, the continuation of early features has not been lost sight of. Here the details of the church built by Bishop Bondington in the thirteenth century furnished models for the work even of the fifteenth century. The lower windows are similar in form, the parapets of the chapter house wing are continued round at the same level as those of the aisles of the choir, and the buttresses are also similar. Attention may be drawn to the curious treatment of the upper water tables of the buttresses of this wing. The slope is divided into two halves, one half rising a little higher than the other. [Illustration: FIG. 596.--St. Mungo’s Cathedral. North Transept.] [Illustration: FIG. 597.--St. Mungo’s Cathedral. Chapter House, from North-West.]