But indeed, having stated our principles of colour, the practice of those principles and the influence of nature and of nature's hints upon that practice are infinite, both in number and variety. The flowers of the field and garden; butterflies, birds, and shells; the pebbles of the shore; above all, the dry seaweeds, lying there, with the evening sun slanting through them. These last are exceedingly like both in colour and texture, or rather in colour and the amount of translucency, to fine old stained-glass; so also are dead leaves. But, in short, the thing is endless. The "wine when it is red" (or amber, as the case may be), even the whisky and water, and whisky without water, side by side, make just those straw and ripe-corn coloured golden-yellows that are so hard to attain in stained-glass (impossible indeed by means of yellow-stain), and yet so much to be desired and sought after.
Will you have more hints still? Well, there are many tropical butterflies, chiefly
among the Pierinf, with broad spaces of yellow dashed with one small spot or flush of vivid orange or red. Now you know how terrible yellow and red may be made to look in a window; for you have seen "ruby" robes in conjunction with "yellow-stain," or the still more horrible combination where ruby has been acided off from a yellow base. But it is a question of the actual quality of the two tints and also of their quantity. What I have spoken of looks horrible because the yellow is of a brassy tone, as stain so often is, especially on green-white glasses, and the red inclining to puce—jam-colour. It is no use talking, therefore, of "red and yellow"—we must say what red and what yellow, and how much of each. A magenta-coloured dahlia and a lemon put together would set, I should think, any teeth on edge; yet ripe corn goes well with poppies, but not too many poppies—while if one wing of our butterfly were of its present yellow and the other wing of the same scarlet as the spot, it would be an ugly object instead of one of the delights of God. It is interesting, it is fascinating to take the hint from such things—to splash the golden wings of
your Resurrection Angel as he rolls away the stone with scarlet beads of sunrise, not seen but felt from where you stand on the pavement below. I want the reader to fully grasp this question of quantity, so I will instance the flower of the mullein which contains almost the very tints of the "lemon," and the "dahlia" I quoted, and yet is beautiful by virtue of its quantities: which may be said to be of a "lemon" yellow and yet can bear (ay! can it not?) the little crimson stamens in the heart of it and its sage-green leaves around.
And there is even something besides "tint" and "quantity." The way you distribute your colour matters very much. Some in washes, some in splashes, some in spots, some in stripes. What will "not do" in one way will often be just right in the other: yes, and the very way you treat your glass when all is chosen and placed together—matt in one place, film in another, chequering, cross-hatching, clothing the raw glass with texture and bringing out its nature and its life.
Do not be afraid; for the things that yet remain to do are numberless. Do
you like the look of deep vivid vermilion-red, upon dark cold green? Look at the hip-loaded rose-briar burning in the last rays of a red October sunset! You get physical pleasure from the sight; the eye seems to vibrate to the harmony as the ear enjoys a chord struck upon the strings. Therefore do not fear. But mind, it must be in nature's actual colour, not merely "green" and "red": for I once saw the head of a celebrated tragic actress painted by a Dutch artist who, to make it as deathly as he could, had placed the ashen face upon a background of emerald-green with spots of actual red sealing-wax. The eye was so affected that the colours swung to and fro, producing in a short time a nausea like sea-sickness. That is not pleasure.
The training of the colour-sense, like all else, should be gradual; springing as it were from small seed. Be reticent, try small things first. You are not likely to be asked to do a great window all at once, even if you have the misfortune to be an independent artist approaching this new art without a gradual training under the service of others. Try some simple scheme from the things of Nature.
Hyacinths look well with their leaves: therefore that green and that blue, with the white of April clouds and the black of the tree-stems in the wood are colours that can be used together.
You must be prepared to find almost a sort of penalty in this habit of looking at everything with the eye of a stained-glass artist. One seems after a time to see natural objects with numbers attached to them corresponding with the numbers of one's glasses in the racks: butterflies flying about labelled "No. 50, deep," or "75a, pale," or a bit of "123, special streaky" in the sunset. But if one does not obtrude this so as to bore one's friends, the little personal discomfort, if it exists, is a very small price to pay for the delight of living in this glorious fairyland of colour.