The most significant use of dusky green as the colour of destiny is Grünewald’s. The indescribable power of space in his _nights_ is equalled only by Rembrandt’s. And the thought suggests itself here, is it possible to say that his bluish-green, the colour in which the interior of a great cathedral is so often clothed, is the specifically _Catholic_ colour?—it being understood that we mean by “Catholic” strictly the Faustian Christianity (with the Eucharist as its centre) that was founded in the Lateran Council of 1215 and fulfilled in the Council of Trent. This colour with its silent grandeur is as remote from the resplendent gold-ground of Early Christian-Byzantine pictures as it is from the gay, loquacious “pagan” colours of the painted Hellenic temples and statues. It is to be noted that the effect of this colour, entirely unlike that of yellow and red, depends upon work being exhibited _indoors_. Classical painting is emphatically a public art, Western just as emphatically a studio-art. The whole of our great oil- painting, from Leonardo to the end of the 18th Century, is not meant for the bright light of day. Here once more we meet the same opposition as that between chamber-music and the free-standing statue. The climatic explanation of the difference is merely superficial; the example of Egyptian painting would suffice to disprove it if disproof were necessary at all. Infinite space meant for Classical feeling complete nothingness, and the use of blue and green, with their powers of dissolving the near and creating the far, would have been a challenge to the absolutism of the foreground and its unit-bodies, and therefore to the very meaning and intent of Apollinian art. To the Apollinian eye, pictures in the colours of Watteau would have been destitute of all essence, things of almost inexpressible emptiness and untruth. By these colours the visually-perceived light-reflecting surface of the picture is made effectively to render, not circumscribed things, but circumambient space. And that is why they are missing in Greece and dominant in the West. IX Arabian art brought the Magian world-feeling to expression by means of the _gold ground_ of its mosaics and pictures. Something of the uncanny wizardry of this, and by implication of its symbolic purpose, is known to us through the mosaics of Ravenna, in the work of the Early Rhenish and especially North Italian masters who were still entirely under the influence of Lombardo-Byzantine models, and last but not least in the Gothic book-illustrations of which the archetypes were the Byzantine purple codices.