thirteenth century window that produces a purple effect, and yet a closer inspection will reveal that there is only red and blue glass used in it, but so cunningly have they been intermingled as to produce a much warmer purple than any sheet of purple glass could render. Some writers would have us believe that the glazier had no choice but to use these small bits in building up his picture, and that therefore the rich glowing effect was the result of chance, and not that of intelligent deliberation. Any one who has been fortunate enough to visit St. Maurice's Cathedral at Angers is amply equipped to refute this theory, and will be prepared to give full credit to the glazier of the thirteenth century, for, in that church, the twelfth century mosaic glass of the nave is readily seen to be composed of much larger fragments than were employed in the choir by the thirteenth century man. These latter in the choir glisten and glitter, while the earlier ones in the nave, composed of larger pieces, do not. This indicates that the improvement shown by the thirteenth century windows over those of the twelfth century was caused by artistic intelligence, and at the expense of more labour to the glazier, because in lessening the size of his panes, he greatly increased the work of leading them together. As he purposely used smaller fragments, he should receive full credit for his splendid results. Those who have been so fortunate as to see the French thirteenth century windows will not only regret the fewness of examples of that period in England, but will also remark the dearth there of the great rose windows so frequent in France. Furthermore, he will notice that in the case of English medallion windows, the medallions are smaller than those across the Channel; this is caused by the fact that the lancets of the Early English school were narrower than contemporary French ones, and therefore necessitated a smaller medallion. While it is true that it is only at Lincoln that one finds the splendid rose windows which reach their greatest perfection in France, compensation for their absence is found in the development in their place of a style of window almost unknown in France, _i.e._, the great east window, of which such superb examples will be seen during the next (or Decorated) period at York, Bristol, and many other places. This difference in the development of the largest light aperture of a church is due to the architect; in France he built the eastern end of his churches round, but in England they were square, thereby permitting a large sheet of glazing at the east end, which the French rounded apse could not afford. It is gratifying to note the way in which the genius of the glazier, no matter where he lived, seized upon and developed to the utmost the artistic possibilities of his glass, and, furthermore, how cleverly he adapted them to the structures prepared for him by his architect. We shall see