SECTION II. INTERFERENCE OF THE LAW OF SIMULTANEOUS CONTRAST OF COLOURS WITH OUR JUDGMENT ON THE PRODUCTIONS OF DIFFERENT ARTS WHICH ADDRESS THE EYES BY COLOURED MATERIALS. INTRODUCTION (843.). CHAPTER I.- ON THE BINARY ASSOCIATIONS OF COLOURS IN A CRITICAL POINT OF VIEW (844.-857.). CHAPTER II. -ON COMPLEX ASSOCIATIONS OF COLOURS IN A CRITICAL CHAPTER III.-ON THE TWOFOLD INFLUENCE, CONSIDERED IN A CRITICAL INTRODUCTION. (843.) AFTER having applied criticism to the judgment we entertain of the colour of a material object, relatively either to its beauty and brilliancy, or to the place its tone assigns to it in the scale of which this object forms part, we must apply it to the judgment concerning the associations of different colours made with the intention of producing an agreeable effect. In order to give the judgment a basis solid beyond all dispute, I shall examine the association of two colours independently of material form, under which the works of nature or of art can offer them to view; and on this occasion I shall sum up many general facts which are found in the Introduction to Part II. of this work (143., &c.), and in several of its divisions. This summary will permit the reader to follow the co-ordinate generalisation, so as to serve as a basis to a critical examination of the products of all the arts which employ coloured materials. After having drawn the principal important conclusions which flow from the binary associations of colours, then I shall occupy myself with their complex associations under the point of view of the harmonies of analogy and of contrast to which they give rise: finally, under a last point of view, I shall take into consideration the influence which the physical nature of the coloured materials the arts employ must specially exercise to attain the aim peculiar to each. CHAPTER I. OF THE BINARY ASSOCIATIONS OF COLOURS CONSIDERED CRITICALLY. (844.) IN order to sum up in few words the generalities which must serve as the bases of our judgment, not only on one colour compared with another of the same sort, but on the associations of two colours which any object whatever presents to our eyes, for example, a stained paper, a stuff, a vestment, or which form part of a picture, I shall consider the case where associated colours are mutually complementary, and that where they are not. 1st CASE. Association of Complementary Colours. (845.) This is the only association where the colours mutually improve, strengthen, and purify each other without going out of their respective scales. This case is so advantageous to the associated colours, that the association is also satisfactory when the colours are not absolutely complementary. So it is also when they are tarnished with grey. Such is the motive which has made me prescribe the complementary association, when we have recourse to the harmonies of contrast in painting, in tapestry, in the arrangement of coloured glass windows, in the assortment of hangings with their borders, in that of stuffs for furniture and clothing, and lastly, in the arrangement of flowers in our gardens. 2nd CASE.-Association of Non-complementary Colours. (846.) The product of this association is distinguished from the preceding in this, the complementary of one of the juxtaposed colours differing from the other colour to which it is added, there must necessarily be a modification of HUE in the two colours, without speaking of the modification of tone, if they are not taken at the same height. Juxtaposed non-complementary colours can certainly give rise to three different results: 1o. They mutually improve each other. 2o. The one is improved, the other loses some of its beauty. 3°. They mutually injure each other. (847.) The greater the difference between the colours, the more the juxtaposition will be favourable to their mutual contrast, and consequently the more analogy they will have, and the more chances there are that the juxtaposition injures their beauty. 1. Two non-complementary colours improve each other by juxtaposition. (848.) Yellow and blue are so dissimilar, that their contrast is always sufficiently great for their juxtaposition to be favourable, although the juxtaposed colours belong to different scales of yellow and blue. 2°. One colour, juxtaposed with another which is not its complementary, is improved, while the latter is injured. (849.) A blue which is improved by a yellow, being placed beside a violet (blue rather than red), may lose some of its beauty by becoming greenish, while the orange it adds to the violet, neutralising the excess of blue of this latter, improves rather than injures it. 3. Two non-complementary colours mutually injure each other. (850.) A violet and a blue reciprocally injure each other, when the first greens the second, and the latter neutralises sufficient of the blue in the violet to make it appear faded. (851.) It might also happen that although the colours juxtaposed are modified, both neither gain nor lose in beauty; that the one gains without the other losing; lastly, that the one neither gains nor loses, while the other loses. (852.) In the association of two colours of equal tone, the height of the tone may have some influence on the beauty of the association. For example, a deep indigo-blue and a red of equal depth gain by the juxtaposition: the first, by losing some violet, will become a pure blue; the second, in acquiring orange, will become brighter. If we take light tones of these same scales, it may happen that the blue will become too green to be good as a blue, and that the red, acquiring orange, will be too yellow to be a pure red. (853.) In the association of two coloured objects of tones very distant from each other, belonging to the same scale, or to scales more or less allied, the contrast of tone may have a favourable influence upon the beauty of the light tone, because, in fact, if the latter is not a pure colour, its juxtaposition with the deep tone upon the whole brightening it, will purify what grey it may have. (854.) It is very necessary for the correction of our judgment of the principles I set up on the binary associations of colours, not to lose sight of all which precedes from paragraph 846., inclusively, concerning colours flat (mat), or deprived of gloss, and that their association be considered independently of the form of the object presenting them, for the twofold reason that the glossiness of the coloured surfaces and the form of the bodies which these surfaces limit in space, are two circumstances capable of modifying the effect of two associated colours: consequently the analysis I have made of the optical effects of colours will be incomplete, if I do not now speak of the possible influence of these causes. Influence of Gloss taken into Consideration in the Effect of Contrast of two Colours. (855.) One of the results to which the observation of contrast of mat colours leads, is the explanation of how the association of one colour with another is favourable or injurious to the ensemble, or only to one of them, in making evident to the eye that, in the most favourable case possible, the optical product of the juxtaposition is composed of two effects: 1°. The effect arising from each of the juxtaposed colours, receiving the complementary of the colour contiguous to it, being strengthened or tinged agreeably by this addition, independently of any augmentation of gloss. 2°. The effect arising from an augmentation of gloss in the two juxtaposed colours. Recalling these results, is to foresee an objection which might have been made to me, namely, that the associations which I have not prescribed, such as those of red with violet, blue with violet, for instance, have a fine effect in the plumage of certain birds, |