177. The colours which have been under my notice are red, orange, yellow, green, blue, violet. Their differences in regard to brilliancy are so great as to admit of their being divided into two groups, one comprising red, orange, yellow, and bright green, the other blue and violet, which, with the same depth of tone, have not the brilliancy of the former. I shall call the first group _luminous colours_, and the second _sombre colours_. But the deep and broken tones of the _luminous scales_ may in many cases be assimilated to the sombre group, as the light tones of blue and violet may sometimes be employed as _luminous_ colours. ARTICLE I. _Colours with White._ Plate 8. A. _Binary Assortments._ 178. All the primary colours gain by their juxtaposition with white, but the binary arrangements which result from them are not equally agreeable; and it is to be remarked that the depth of tone of a colour has a great influence upon the effect of its assortment with white. The binary assortments in the order of their greatest beauty, are as follows:—_light blue_ and white, _rose_ and white, _deep yellow_ and white, _bright green_ and white, _violet_ and white, _orange_ and white. Dark blue and dark red produce, with white, too strong a contrast of tone to allow of their assortment being as agreeable as that of their light tones. On the contrary, yellow being a light colour, we must take the normal or deepest tone of yellow to produce its most beautiful effect. Dark green and violet contrast too much in tone with white for their combination to be as agreeable as those which are made with the light tones of these colours. The objection which can be made to the combination of orange and white is that of too much brilliancy; yet I should not be surprised to find that many persons preferred it to that of violet and white. B. _Tertiary Assortments of Colours complementary to each other with White._ 179. It is to me impossible to establish an order of beauty among binary combinations of primary complementary colours. I shall therefore only describe the effect of white interposed between the binary complementary assortments, or between each of the complementary colours. [Illustration: PLATE VIII.] 180. 1. _Red and Green_ are of all complementary colours the most equal in depth; for red, as regards its brilliancy, is midway between yellow and blue; and in green these two extremes are united. 2. The arrangement, white, red, green, white, &c., is not decidedly superior to the preceding, at least when the colours are not deep. 3. The arrangement white, red, white, green, white, &c., seems to me inferior to the preceding. 181. 1. _Blue and Orange_ are more opposed to each other than red and green, because the least brilliant colour blue, is separated, while the most brilliant are combined in orange. 2. The arrangement, _white, orange, blue, white_, &c., is agreeable. 3. The arrangement, _white, orange, white, blue, white_ &c., is also agreeable.