Principles of Decorative Design / Fourth Edition

by Christopher Dresser

This latter table shows at a glance how each of the secondary and tertiary colours is formed, and the proportions in which they harmonise. It also shows why the three tertiary colours are called respectively the yellow tertiary, the red tertiary, and the blue tertiary, for into each tertiary two equivalents[11] of one primary enter, and one equivalent of each of the other primaries. Thus, in citrine we find two equivalents of yellow, and one each of red and blue; hence it is the yellow tertiary. In russet we find two equivalents of red, and one each of blue and of yellow; and in olive two of blue, and one each of red and yellow. Hence they are respectively the red and blue tertiaries.

Figs 24 and 25 are diagrams of harmony. I have connected in the centre, by three similar lines, the colours which form a harmony; thus, blue, red, and yellow harmonise when placed together. Purple, green, and orange also harmonise (I have connected them by dotted lines in the first of the two diagrams). But when two colours are to produce a harmony, the one will be a primary colour, and the other a secondary formed of the other two primary colours (for the presence of the three primary colours is necessary to a harmony), or the one will be a secondary, and the other a tertiary colour formed of the two remaining secondary colours. Such harmonies I have placed opposite to each other; thus blue, a primary, harmonises with orange, a secondary; yellow with purple; and red with green; and the secondary colour is placed between the two primary colours of which it is formed; thus, orange is formed of red and yellow, between which it stands; green, of blue and yellow; and purple, of blue and red. In the second of the two diagrams we see that purple, green, and orange produce a harmony, so do olive, russet, and citrine. We also see that purple and citrine harmonise, and green and russet, and orange and olive.

Continuing this diagrammatic form of illustration, we may set forth the quantities in which the various colours harmonise: thus:—

To those who are about to practise ornamentation, it is very important that they have in the mind's eye a tolerably accurate idea of the relative quantities of the various colours necessary to harmony, even where the colours are considered as existing in a state of absolute purity. We have rarely, however, to use the brightest blues, reds, and yellows which pigments furnish, and even these are but poor representatives of the potent colours of light as seen in the rainbow, and with the agency of the prism; nevertheless, a knowledge of the quantities in which these pure colours harmonise is very desirable. The proportions in which we have stated that colours perfectly harmonise, and in which the primary colours combine to form the secondaries, and the secondaries the tertiaries, are given in respect to the colours of light, and not of pigments or paints, which, as we have just said, are more or less base representatives of the pure colours of light. Yet certain pigments may, for our purpose, be regarded as representing pure colours. Thus, the purest real ultramarine we will regard as blue (cobalt is rather green, that is, it has a little yellow in it, and the French and German ultramarines are generally rather purple, or have a little red in them, yet the best of these latter is a tolerably pure colour), the purest French carmine as red (common carmine is frequently rather crimson, that is, has blue in it; vermilion is much too yellow), and lemon-chrome as yellow (the chrome selected must be without any green shade, and without any orange shade, however slight); and these pigments will be found to represent the colours of the prism as nearly as any that can be found. I would recommend the learner to get a small quantity of these colours in their powder form, substituting the best pale German ultramarine for real ultramarine, as the latter is of high price,[12] and to fill the various circles of our diagrams, which represent the primary colours, with these pigments, mixing them with a little dissolved gum arabic and water—just ufficient to prevent the colours from rubbing off the paper. The secondary colours will be fairly represented by pale-green lake, often called drop-green, by orange-chrome—that of about the colour of a ripe, rather deep-coloured, orange-rind—and the purple by the admixture of pale German ultramarine and crimson-lake, in about equal proportions, with a little white to bring it to the same depth as the green. I cannot name any pigments which would well represent the tertiary colours. Citrine is about the colour of candied lemon-peel; olive about the colour of candied citron-peel, and russet is often seen on the skin of certain apples called "russet apples," in the form of a slight roughness; but this russet is in many cases not quite sufficiently red to represent the colour bearing the same name. Iron rust is rather too yellow. This colour should bear the same relation to red that the candied lemon-peel does to yellow.

If the student will try carefully to realise these colours, and will fill up the circles in our diagrams with them, he will thereby be much assisted in his studies; but it will be still better if he prepare fresh diagrams on a larger scale, and use squares instead of circles. I should recommend, and that I do strongly, that the student work out all the diagrams which I have suggested on a tolerably large scale, using the colours where I have used words. I should also advise him to do an ornament, say in red on a gold ground, and outline this red ornament with a deeper red; to do a gold ornament on a coloured ground, and outline it with black; and indeed to carefully work out an ornamental illustration of our propositions, Nos. 24, 25, 26, and 27, and to keep these before him till he is so impressed by them as to feel the principle which they set forth. This should be done on a large scale in all our designing-rooms and art-workshops.

As we shall have to refer to colours by naming pigments, and as I am constantly asked what pigments I employ, I shall enumerate the paints in my colour-box; but I shall place a dagger against those which I have in my private box, and which I do not supply in my offices; but these I seldom use. Of yellows I have [14]king's yellow (not a permanent colour), [14]very pale chrome, lemon-chrome (about the colour of a ripe lemon), middle-chrome (half-way between the lemon and orange-chrome), orange-chrome (about the colour of the rind of a ripe orange), [14]yellow-lake, [14]Indian yellow. Of reds—vermilion, carmine, crimson-lake. Of blues—[14]cobalt, German ultramarine, both deep and pale, Antwerp blue, indigo. Of greens—emerald, green-lake, pale and deep. Of browns—raw Turkey umber, vandyke, Venetian red, purple-brown, brown-lake. Besides these I have what is called celestial blue, which is a very pure and intense turquoise, vegetable black, flake white, and gold bronze.[13]

There are certain facts connected with the mixing of colours which must never be lost sight of; thus, while the colours of light co-mingle without any deterioration, or loss of brilliancy, pigments or paints will not do so, but by admixture tend to destroy one another. This takes place only to a small extent when but two primary colours are combined; but if any of the third primary enters into the composition of a tint, a decided deterioration, or loss of intensity, occurs.

For this reason we employ many pigments, so as to avoid as far as possible the mixing of colours. But there is another reason why the great admixture of colours is undesirable. Colours are chemical agents, and in some cases the various pigments act chemically on one another. Of all colours yellows suffer most by admixture with other colours: but this is accounted for by their delicacy and purity. For this reason I use a greater variety of yellow pigments than of red or blue.[14]