With too strong direct sun the windows are said to suffer, and become a cluster of jewels--a delirium of coloured light. The lines, too, have different degrees of merit. These criticisms seldom strike a chance traveller, but he invariably makes the discovery that the designs within the medallions are childish. He may easily correct them, if he likes, and see what would happen to the window; but although this is the alphabet of art, and we are past spelling words of one syllable, the criticism teaches at least one lesson. Primitive man seems to have had a natural colour-sense, instinctive like the scent of a dog. Society has no right to feel it as a moral reproach to be told that it has reached an age when it can no longer depend, as in childhood, on its taste, or smell, or sight, or hearing, or memory; the fact seems likely enough, and in no way sinful; yet society always denies it, and is invariably angry about it; and, therefore, one had better not say it. On the other hand, we can leave Delacroix and his school to fight out the battle they began against Ingres and his school, in French art, nearly a hundred years ago, which turned in substance on the same point. Ingres held that the first motive in colour-decoration was line, and that a picture which was well drawn was well enough coloured. Society seemed, on the whole, to agree with him. Society in the twelfth century agreed with Delacroix. The French held then that the first point in colour-decoration was colour, and they never hesitated to put their colour where they wanted it, or cared whether a green camel or a pink lion looked like a dog or a donkey provided they got their harmony or value. Everything except colour was sacrificed to line in the large sense, but details of drawing were conventional and subordinate. So we laugh to see a knight with a blue face, on a green horse, that looks as though drawn by a four-year-old child, and probably the artist laughed, too; but he was a colourist, and never sacrificed his colour for a laugh. We tourists assume commonly that he knew no better. In our simple faith in ourselves, great hope abides, for it shows an earnestness hardly less than that of the crusaders; but in the matter of colour one is perhaps less convinced, or more open to curiosity. No school of colour exists in our world to-day, while the Middle Ages had a dozen; but it is certainly true that these twelfth-century windows break the French tradition. They had no antecedent, and no fit succession. All the authorities dwell on their exceptional character. One is sorely tempted to suspect that they were in some way an accident; that such an art could not have sprung, in such perfection, out of nothing, had it been really French; that it must have had its home elsewhere--on the Rhine--in Italy--in Byzantium-- or in Bagdad.