Digitized by the Internet Archive in 2018 with funding from Getty Research Institute https://archive.org/details/lawsofcontrastof00chev_1 PRIMARY COLOURS. And their Complernentaries See page 17- THE LAWS OF CONTRAST OF COLOUR: HD THEIR APPLICATION TO THE ARTS OP PAINTING, DECORATION OF BUILDINGS, MOSAIC WORK, TAPESTRY AND CARPET WEAVING, CALICO PRINTING, DRESS, PAPER STAINING, PRINTING, Illumination, S’anbsrapt anb Jrloluer (Sarbtning, ttr. By M. E. CHEYREUL, DIBECIOB OF TUB DTE WOEIS 05 THE GOBELINS, ETC. ETC. TRANSLATED FROM THE FRENCH BY JOHN SPANTON. ILLUSTRATED WITH DESIGNS. i*fae> ias7 LONDON; G, ROUTLEDGE & CO., FAEK1NGD0N STREET. NEW YORK: 18, BEEKMAN STREET. 1857. LONDON: -SAVJLL AND EDWARDS, PRINTERS, CHANDOS-STKEET. GETTY Ctr.3 Libi-.'.rY CONTENTS. Introduction . PAGE 1 PAET THE FIRST. Section I.—On the law of simultaneous contrast OF colours, and of its demonstration by means OF EXPERIMENT .. Chap. I.—Manner of observing the Phenomena of the Simultaneous Contrast of Colours. Definition of Simultaneous Contrast. Chap. II.—The Law of the Simultaneous Contrast of Colours, and the Formula which represents it. Chap. III.—The Law of Simultaneous Contrast of Colours demonstrated by the Juxtaposition of a cer¬ tain Number of Coloured Bodies. Chap. IV.—On the Juxtaposition of Coloured Surfaces with White. Chap. V.—On the Juxtaposition of Coloured Bodies with Black. Chap. VI.—On the Juxtaposition of Coloured Bodies with Grey.. Chap. VII.—On the Juxtaposition of Coloured Bodies belonging to the Colours of the same Group of Co¬ loured Rays. 4 4 10 18 10 21 24 IV CONTENTS. 'page Chap. VIII.—On the Application of the Law of Con¬ trast to the Hypothesis that Led, Yellow, and Blue are the only Primary Colours; and that Orange, Green, Indigo, and Violet are Secondary or Com¬ posite Colours. Section II._On the distinction between simultaneous, SUCCESSIVE, AND MIXED CONTRAST OF COLOURS, AND ON THE CONNEXION BETWEEN THE EXPERIMENTS MADE BT THE AUTHOR, AND THOSE PREVIOUSLY MADE BY OTHER OB¬ SERVERS. DISTINCTION BETWEEN SIMULTANEOUS, SUC¬ CESSIVE, AND MIXED CONTRAST OF COLOURS .... 29 PAET THE SECOND. ON THE APPLICATION OF THE LAW OF SIMULTANEOUS CON¬ TRAST OF COLOURS . Introduction. Definition of the words Tones, Scales, and Hues . . Of Diagrams designed to represent and define Colours and their Modifications. Harmony of Colours -. Assortments of Red, Orange, Yellow, Green, Blue, and Violet with White, Black, and Grey. Colours with White.. Colours with Black.* Colours with Grey. 34 34 34 36 46 49 50 54 58 First Division.—Imitation of coloured objects with COLOURED MATERIALS IN A STATE OF INFINITE DIVISION 68 Introduction. Painting on the System of Chiaro-’scuro.69 Painting on the System of Flat Tints.81 SECTION III.— On COLOURING IN PAINTING . 82 Chap. I.— On Colouring.. Of Aerial Perspective. 83 Of Colouring in respect to the Harmony of the Colours of the various Objects composing the Picture .... 85 CONTEXTS. V PAGE ■Chap. II.—Utility of the Law of Simultaneous Contrast of Colours in the Art of Colouring.87 Utility of this Law in order to imitate promptly and surely the Modification of Light on the Model ... 89 Utility of the Law in order to Harmonize those Co¬ lours of a Composition which are inherent to the Nature of the Object represented.95 Second Division.—Imitation of coloured objects by MATERIALS OF A DEFINITE SIZE, AS THREADS, &C. .' 102 Chap. 1.—On the Elements of Gobelins Tapestry . . 104 Rule I.—The Binary Mixture of Primary Colours. 104 Rule II.—The Mixture of Complementary Colours 105 Rule III.—The Mixture of the Three Primary Co¬ lours in such proportions that they do not become neu¬ tralized, because one or the other of them is in excess . 108 Third Division.—Colour printing. 118 On Calico Printing, and printing Paper-hangings . . . 118 False Judgment of the Value of Recipes for Colouring Compositions.119 Chap. II.—On the Law of Simultaneous Contrast of Co¬ lours in relation to Paper-hangings with Figures, Land¬ scapes, or large Flowers of varied Colours . . . . 121 On the Law of Simultaneous Contrast of Colours rela¬ tively to the Borders of Paper-hangings.123 Printed or written Characters on Papers of different Colours.136 On the Assortment of Colours for reading by diffused Daylight.- ..138 Fourth Division.—Employment of colours in archi¬ tecture .138 1. On the Employment of Colours in Egyptian Architecture.138 2. On the Employment of Colours in Greek Archi¬ tecture .139 3. On the Employment of Colours in Gothic Archi¬ tecture ..141 VI CONTENTS. pagi Application to the Interior of Edifices.143 On the Assortment of Stuffs with the Wood of Seats . ...143 On the Selection of Frames for Pictures and En¬ gravings .145 On the General Decoration of the Interiors of Churches ..147 On the Decoration of Museums and Galleries . . 14 Decorations of the Interior of Houses ...... 152 On the Assortment of Colours in Interiors, the Walls of which are panelled or covered with Marble, Stucco, or Painted Wood ..163 Fifth Division.—Clothing . ..165 I. Men's Clothing ..165 Of the Advantages of Contrast, considered with regard to the apparent Cleanliness of Cloth for Clothing . . 165 II. Female Clothing.167 Colours for the Dress of Women with White Skins 167 Of the Colours of the Hair and Head-dress . . . 168 Of the Colours of the Complexion and the contiguous Drapery..169 The Head-dress in relation to the Coloured Hays which it may reflect upon the Skin.171 Famhaired Type ..175 Type with Black Hair.176 On the Assortment of Colours in the Dress of Women with Copper-coloured Skins.177 On the Assortment of Colours in the Dress of Women with Black or Olive Skins.17 T APPLICATIONS TO HORTICULTURE. On the Art of arranging ornamental Plants in Gardens, so as to derive the greatest possible advantage from the Colours of their Flowers.ISO Assortments of Flowers where the Plants are apart . . . 181 Assortments relating to the Harmonies of Contrast of Hues 182 CONTENTS VIL P ACS Assortments as to Harmony of Analogy . . . . . . 182 On the Art of assorting Ligneous Plants in Gardens, so as to derive the best possible advantage from the Colour of their Foliage.184 On the Distribution and Planting of Trees, &c., in Masses 185 Chap. I. Of Lines of Plants.187 Of the Lines of Plants called Screens.188 Of Lines of Plants considered as Elements of Masses 188 Of Homogeneous Masses.189 Of Heterogeneous or Varied Masses.190 Isolated.190 Contrast of Colours.194 Repetition .194 Symmetry.190 General Harmony.19S Sixth Division.—Intervention of the preceding prin¬ ciples IN THE judgment of coloured objects, rela¬ tively TO THEIR COLOURS, CONSIDERED INDIVIDUALLY, AND TO THE MANNER IN WHICH THEY ARE ASSOCIATED . 197 On the Connexion of the Law of Simultaneous Con¬ trast of Colours with the Judgment we form upon all Coloured Bodies, under the relations of the respective Beauty or Purity of their Colours, and of the Equality of the Distance of their Tones if these bodies belong to the same scale.205 On the Comparison of two Samples of thesame Colour 206 Influence of a Surrounding Colour upon one Colour when compared with another.206 On the Effect of Contrast upon the Browns and the Lights of most of the Scales of Wood and Silk em¬ ployed in Tapestry and Carpets.208 Means afforded by Contrast for ascertaining whether the Tones of a Scale of Colour are equidistant . . . 209 Of the Binary Associations of Colours, critically con¬ sidered .210 Of the Complex Association of Colours, reviewed critically. 214 viii CONTENTS. Of the Arts which address the Eye by employing Coloured Materials of a certain size, considered rela¬ tively to the Physical Condition of these Materials, and to the Peculiarity of the Art employing them . . . Tapestries, Carpets, Mosaics, and Coloured Glass Windows, corresponding to Paintings in Chiaro- ’scuro ........ . Of the Disposition of the Mind of the Spectator in respect to the Judgment he forms of an Object of Art which attracts his eye ....... .... PA&B 218 219 225 TRANSLATOR’S PREFACE. Colour, a universal source of enjoyment, so essential an element of decorative art, lias not been hitherto the subject of such investigations as to place its powers, harmonies, and discordances among matters of scientific certainty. A few traditionary dogmas have been the only guide of ordinary workmen, while success in design, as well as in the higher regions of art, has been depen¬ dent upon that rare union of faculties vaguely denoted by the indefinite, unsatisfactory term, “ taste.” The arrangement of colours in manufactures of Eng¬ lish design—since the decline of mediaeval art—has commonly been condemned as notoriously arbitrary, destitute of any reference to principle, and deficient in that satisfying richness and beauty which result from harmonious combinations. Although often overcharged with colour, and of costly elaboration, our manufactures have too often proved that the designer—in ignorance of a true, infallible standard—has mistaken gaudiness for splendour, and capricious strangeness for improve¬ ment ; and, for want of a better claim to popular favour, has constantly sought it by “ leaning on novelty, his fickle, frail support.” X translator’s preface. The established, preference of French designs was shown, by the Great Exhibition of 1851, to be, in the main, well founded ; and one of the leading causes of the perfect success of some objects was found in the fact, that they had been designed and executed in ac¬ cordance with a well-defined set of principles, exten¬ sively taught in France to designers, workmen, and others. These principles it is the purpose of this book to set forth, to illustrate, and to apply to every art of which the choice and arrangement of colours is an element. The author, M. Chevreul, before the publication of this work, had gained high reputation by his researches in organic chemistry. In his “ Considerations sur I Analyse Organique,” he enunciated principles which, carried into practice in his “ Recherches sur les Corps Gras d’origine animal,'’ opened the path ■which has been rendered illustrious by Liebig and others. But, being appointed Director of the Dye Works of the Gobelins, he was compelled to abandon these researches—the field in which, “ having sown, he had, as it were, only to reap,”—that he might fully investigate the principles involved in the assortment of colours. M. Chevreul’s earnest attention to this inquiry was continued during ten years, with ample opportunities for investigation. For twenty-five years he has been in the habit of lecturing to workmen, artists, and others. The undisputed superiority of those French manu¬ factures in which these instructions have been fully carried out, has evinced his success and rewarded his exertions. Aware of the important influence of such knowledge, TRANSLATOR S PREFACE. XI the Chamber of Commerce of Lyons solicited and obtained from the French Government permission for M. Chevreul to lecture there to the artisans and others, to ■whom printed copies of the lectures were afterwards gratuitously distributed. As the present Work contains the substance of these instructions, we may hope that our own industrious coun¬ trymen may not long be without a similar advantage. The value of this book has been' universally recog¬ nised, and it has already been translated into several languages, although but recently into our own. A recent critic has said, with equal truth and eloquence, —“Rarely has a subject of inquiry, so fraught with beautiful and ready applications, been presented to us. To be familiar with this book is to possess a new sense. Every object in art and nature speaks a new and exciting language. Colour becomes music to the eye. We become impatient of any violent infringement of the principles of harmony, and seek every opportunity of putting our newly-acquired knowledge into practice. The minuteness of investigation, and the copiousness of illustration which characterize this volume are truly remarkable ; the most untutored mind cannot fail to understand it, if steady attention be given. As a pre¬ paration for a course of scientific study, it is invaluable, for it is an excellent example of the Baconian method of investigation.” ■ ? . \ i. EXTRACTS FROM THE AUTHOR’S PREFACE. In seeking to discover the causes of the complaint made of the quality of certain colours prepared in the dyeing laboratory of the Gobelins, I was at once con¬ vinced, that, although the complaints concerning the instability of the light blues, greys, and browns, might be well founded, there were others, especially those of a want of vigour in the blacks employed for the shadows of blue and violet draperies, which were not so; for, having procured black-dyed wools from the most celebrated dye-works in France and other countries, and having found that they were not superior to those of the Gobelins, I saw that the want of vigour alleged against the blacks was owing to the colours contiguous to them, and that the matter was involved in the phenomena of the cryntrast of colours. It was thus demonstrated to me that I had two absolutely distinct subjects to investigate, in order to fulfil my duties as Director of the Dye Works; the first being the contrast of colours, considered in the most general manner, both in relation to science, and as to XIV EXTRACTS PROM AUTHOR’S PREFACE. its applications : tlie second—the chemistry of dyeing. These are the two centres around which have converged all my researches during the last ten years. In fact, numerous observations made during several months, on the view of coloured objects, which were veri¬ fied by my pupils and others, much accustomed in their profession to judge of colours and to appreciate the least differences between them, have been collected and de¬ scribed as well-known facts. Upon reflecting on the mutual relations of these facts, and in seeking the prin¬ ciple of which they were the results, I was led to the dis¬ covery of that which I have named the “ Law of Simul¬ taneous Contrast of Colours.” Thus this work is the fruit of the method & posteriori: facts are observed, de¬ fined, described, then generalized in a simple expression, which has all the characters of a law of nature. This law, once demonstrated, becomes a means, priori, of assorting coloured objects so as to obtain their best pos¬ sible effect, according to the taste of the person who arranges them; it becomes also a means of estimating whether the eyes are well organized for seeing and judg¬ ing of colours ; and whether painters have copied exactly the colours of known objects. In reviewing the Law of Contrast with regard to its application, and in submitting to experiment all the laws which appear to me to result from it, I have been led to extend it to the arts of tapestry, to the various sorts of painting and printing, to illuminating, horticul¬ ture, 0^ INTRODUCTION. 1. A hay of solar light is composed of an indetermi¬ nate number of variously coloured rays, 'which are dis¬ tributed into groups, termed red rays, orange rays, yel¬ low rays, green rays, blue rays, indigo rays, violet rays. 2. But all the rays comprised in the same group, the red for example, are not identical in colour; on the contrary, they may be considered as differing more or less among themselves, although we recognise the im¬ pression they produce separately, as comprised in that which we ascribe to red light. 3. When light is reflected by an opaque white body, it is not modified in proportion to the variously coloured rays which constitute white light; but, 1 . If the body is not polished, every point of its surface is to be con¬ sidered as dispersing the white light which falls upon it, in all directions, into the surrounding space; so that the point becomes visible to an eye placed in the direc¬ tion of one of its rays. We may easily conceive that the image of the body, in a given position, is composed of the sum of the physical points, which send to the eye so placed, a portion of the light which each point B 2 harmony and contrast of colours. radiates. 2. If the body is 'polished, as, for example, the surface of a mirror, a portion of the light is irregularly reflected, as in the preceding case ; while another por¬ tion is regularly reflected, giving to the mirror the pro¬ perty of presenting to an eye, suitably placed, the image of the body which sends its light to the reflector. One consequence of this distinction is, that if we regard two plane surfaces which reflect white light, and differ from each other only in polish, it will happen that where the unpolished surface is visible, all its parts will be equally, or almost equally, illuminated; while the eye, when in a position to receive only that light which it reflects irregularly, will receive very little light from the polished surface ; but it will receive much more light when in a position to receive that which is regularly reflected. 4. If the light which falls on a body is completely absorbed by that body, so that it disappears from sight, as in falling into a perfectly dark cavity, then the body appears to us black; and it becomes visible only be¬ cause it is contiguous to surfaces which reflect or trans¬ mit light. We know of no bodies winch are perfectly black, and it is only because they reflect a little white light that we judge they have relief, like other material objects. 5. When light is reflected by an opaque coloured body, there is always a reflection of white light, and a reflection of coloured light; the latter is owing to the fact that the body absorbs or extinguishes within itself some of the coloured rays, and reflects the others. It is evident that the absorbed coloured rays are of a different colour from the reflected coloured rays ; and farther, that if these be reunited with the former, white light will be reproduced. It is evident, also, that unpolished opaque INTRODUCTION. .3 bodies reflect irregularly white light, and the coloured light which makes them appear coloured; and that those which are polished reflect irregularly a portion only of these two lights, while they reflect regularly the other portion. 6. It thus appears, by what has been said concerning the physical composition of solar light, that if the whole of the coloured light which is absorbed by a coloured body were reunited with the whole of the light which it re¬ flects, white light would result. IS ow, it is this property of two variously coloured lights, taken in a certain pro¬ portion, to reproduce white light, that we express by the words coloured lights complementary to each other, or ojrm.'plementary colours. It is in this sense that we say, Eed is complementary to Green, and vice versa. 0ran S e „ „ Blue, „ Greenish Yellow „ Violet, „ Indigo „ Orange Yellow, „ 7. It must not be supposed that a red body, a yellow body, (tc. reflects, besides white light, only the red rays or yellow rays, &c., each of these bodies reflects also every sort of coloured rays; but, the rays which cause us to judge it to be red or yellow, &c., being more numerous than the others, produce more effect than Biej , jet, the latter have an undoubted influence in modifying the action of red and yellow rays upon the organ of sight. This explains the innumerable diver¬ sities of colour observable among various red bodies, various yellow bodies, die. It is difficult not to admit , arfl0n g these diversely coloured rays reflected by bodies, there are a certain number which, complemen¬ tary to each other, must reproduce white light upon reaching the retina. B 2 HARMONY AND CONTRAST OF COLOURS. PART THE FIRST. SECTION THE FIRST. OF THE LAW OF SIMULTANEOUS CONTRAST OF COLOURS, AND OF ITS DEMONSTRATION BY MEANS OF EXPERI¬ MENT. CHAPTER I. Manner of observing the Phenomena of the Simultaneous Contrast of Colours.—Definition of Simultaneous Contrast. 8. If we look at tlie same time at two stripes of un¬ equal tints of the same colour, or at two stripes of equal tints of different colours, in juxtaposition, that is to say, contiguous by one of their edges, the eye will per¬ ceive, if the stripes be not too wide, certain modifica¬ tions; in the first case affecting the intensity of the two tints, in the second, the optical composition of the two colours so placed. Now as these modifications cause the colours to appear, when looked at together, more different than they really are, I have given to them the name of the simultaneous contrast of colours. The modi¬ fication which affects the intensity of colour, I term contrast of tone; and the modification which affects the optical composition of the contiguous colours, I term contrast of colour. The twofold phenomena of contrast of colour and contrast of tone may be readily shown by the following Experimental Demonstration of Contrast of Tone. 9. Let the two halves of a sheet of unglazed paper, about twenty inches square, be coloured clear grey, by a SIMULTANEOUS CONTRAST. 5 mixture of chalk and black; fix them, in any way, upon a piece of unbleached linen, placed across a window, at the distance of twelve inches asunder. The two halves of another piece of similar paper, but of a darker grey, and coloured ■with the same substances, are to be placed about twelve inches from the former. (See Fig. 1.) Upon looking at the four half sheets for a few seconds, it will be seen that A contiguous to A' will be lighter than A', while, on the contrary, B' will seem darker than B. 10. It is easy to demonstrate that the modification is not equally intense over the whole of the surfaces A A' and B B', but that it becomes gradually feebler from the line of contact. This may be proved by placing a card, so cut, that A and B may each present three grey stripes, as shown in Fig. 3. The stripes 1 1 are more modified than the stripes 2 2, and these are more so than the stripes 3 3. However, in order that this modification may be effected, it is not absolutely necessary that O and P should touch; for if the stripes 1 1 be covered, the stripes 2 2, 3 3 will be modified. 11. The following experiment, which is simply the result of the two preceding (9 and 10), is well suited to demonstrate the extent of contrast of tone. Upon a sheet of cardboard divided into ten stripes, each about a quarter of an inch broad, lay a uniform tint of Indian ink. As soon as it is dry, lay a second tint on all the stripes except the first. As soon as the second is dry, lay a third on all the stripes except the first and second, and so on of all the rest, so as to have ten flat tints, gradually increasing in depth from the first to the last. (See Fig. 3.) If ten strips of paper of the same grey, but each of a different tone, be laid upon a cardboard, in the preceding gradation, it will serve the same purpose. 6 HARMONY AND CONTRAST OF COLOURS. Upon looking at the cardboard, it will be seen that the strips, instead of presenting flat tints, will each appear of a tone diminishing in intensity from the edge a a to the edge bb. In the stripe 1, the contrast is produced simply by the contiguity of the edge b b with the edge a a of the stripe 2 ; in the stripe 10, it is simply by the contiguity of the edge a a with the edge bb of the stripe 9. But in each of the intermediate stripes 2, 3, 4, 5, 6, 7, 8, 9, the contrast is produced by a double cause ; partly by the contiguity of the edge a a with the edge bb of the stripe which precedes it, partly by the contiguity of the edge bb with the edge a a of the daikei tint which follows it. The first cause tends to raise the tone of the half of the intermediate stripe, while the second cause tends to lower the tone of the other half of the same stripe. In consequence of this contrast, the stripes seen from a proper distance, resemble channels rather than flat surfaces. For, in the stripes 2 and 3 for instance, the grey is weakened from the edge a a to the edge b b, presenting to the eye the same effect as if the light fell upon a channelled surface ; there is however this difference, that in the real channelling the enlight¬ ened part would throw a reflection upon the dark portion. 12. Contrast of tone occurs with colours so called as well as with grey j thus to repeat the experiment (9), fig. 1, with the halves oo of a sheet of paper of a light- tint of a certain colour, and the two halves pp of a sheet of paper of a darker tint of the same colour, it will be seen that o contiguous to p will be darker than o', and p darker than p'. In short, it may be demonstrated as has been done (10) that the modification of colours in juxtaposition becomes weaker in proportion to their EXPERIMENTAL DEMONSTRATION. I distance from tlie line of contact; and in order to observe this effect in bodies which are not contiguous, it is only necessary to experiment as described in (10). The colours experimented upon must be as nearly as possible of equal intensity. 13. Experimental Demonstration of Contrast of Colour. —If we arrange as before, the two halves of an unglazed coloured sheet of paper, and two halves of another sheet of a different colour, but as nearly as possible of equal intensity, or rather of tone (8), upon looking at the four half-sheets o o', pp' for a few seconds, we shall see that o differs from o' and p from pJ; consequently the two half¬ sheets, o p, seem to undergo a reciprocal modification of tint, which is rendered apparent by comparing their colours with those of o' and p'. Eed inclines to Yiolet. Orange 77 Yellow. Eed 77 Yiolet, or is less Yellow Yellow 77 Green „ Eed. Eed 77 Yellow. Blue 77 Green. Eed 77 Yellow. Indigo 77 Blue. Eed 77 Yellow. Yiolet 77 Indigo. Orange 77 Eed. Yellow 77 Bright Green. Orange 77 Bright Eed. Green 77 Blue. Orange 77 Yellow. Indigo 77 Blue. Orange 77 Yellow. Yiolet 77 Indigo. 8 HARMONY AND CONTRAST OF COLOURS. 10 . 11 . 12 . 13. 14. 15. 16. 17. C Yellow inclines C Green „ ( Yellow „ 1 Blue „ f Green „ t Blue „ f Green „ \ Indigo „ ( Green „ t Violet „ f Blue „ 1 Indigo „ f Blue „ ( Violet „ f Indigo „ ( Violet ,, to Bright Orange. Blue. Orange. Indigo. Yellow. Indigo. Yellow. Violet. Yellow. Bed. Green. Deep Violet. Green. Bed. Blue. Bed. 15. It thus appears from the experiments described in this chapter that two coloured surfaces in juxtaposition, viewed simultaneously, present to the eye two modi¬ fications—one relative to the depth of tone of their respective colours, and the other relative to the physical composition of those colours. CHAPTEB II. The Law of the Simultaneous Contrast of Colours, and tlw Formula which represents it. 16. After I had assured myself that the preceding phenomena were constant for my sight when it was not fatigued, and that many persons, accustomed to judge of colours, saw them as I did, I sought to reduce them to an expression sufficiently general to render it possible to predicate the effect which would be produced upon the FORMULA 9 organ of vision by the juxtaposition of two given colours. All the phenomena that I have observed seem to depend upon a very simple law, which in its most general sense may be enunciated in these terms : When two contiguous colours are seen at the same time, they appear as dis¬ similar as possible, both with regard to their optical composition and their depth of tone. Therefore there may be at once simultaneous contrast of colour, properly so called, and simultaneous contrast of tone. 17. Now two colours in juxtaposition, o and p, will differ from each other in the greatest possible degree when the complementary of o is added to p, and the complementary of p is added to o ; indeed by the juxta¬ position of o and p, the rays of the colour p, which o reflects when it is seen alone, and which are active in that case, cease to be so when o and p are in juxta¬ position. Now under these circumstances, each of the two colours, losing what it has analogous to the other, must be so much more different from it. 18. The following formulae will illustrate this :— Let us represent— The colour of the stripe O by the colour a pirn white B, „ „ P „ a! plus white B', the complementary colour of a by C, 5} » ® JJ C> ') the colours of the two stripes seen separately are— Colour of O = a + B ; colour of P — a' + B'; by tixtaposition they become— Colour of O — a + B + d, P = a' + B ' + c. We will now show that this expression amounts to taking away the rays of a’ from the colour a of O (15), and to taking away the rays of the colour a from a! of P. 10 HARMONY AND CONTRAST OF COLOURS. For let us suppose— B reduced into two portions, white = 6 + white = (a' + c'), B'reduced into two portions,white = V + white = (a + c). The colours of the two stripes seen separately are— The colour of 0 = a + b + a' + c', and the colour of P = a' + V + a + c. By juxtaposition they become— The colour of 0 = a + b + d, and the colour of P = a' + V + c. An expression which is evidently the same as the former, except for the values of B and B'. 19. I have said that simultaneous contrast may at the same time affect the optical composition of colours, and the depth of their tone ; consequently, when colours are not of the same depth, that which is deep appears deeper, and that which is light appears lighter ; that is to say, the former appears to lose white light, while the latter seems to reflect more of it. Thus there may he, in looking at two contiguous colours, simultaneous contrast of colours and simultaneous contrast of tone. CHAPTER III. The Law of Simultaneous Contrast of Colours demonstrated by the Juxtaposition of a certain Number of Coloured Bodies. 20. Let us now apply the above formula to the seventeen observations of Chapter I., and we shall see that the modifications of contiguous colours are precisely those which would result from the addition to each of them of the complementary of the contiguous colour (18). The rank these colours occupy in Chapter I. may be readily noted, as I have attached to each the number applied to it in that chapter. And for the comple¬ mentary of each colour see (6). EFFECTS OF JUXTAPOSITION 11 ] 2 HARMONY AND CONTRAST OF COLOURS. S o e % -4-D • pH 3 - ee c bX) Ph HH o fcX) . S3 O ce ^ 6 3 ce pH hH o 1 <3 £ bX) bX) S 3 .s ft? »>$ '1 "8 Js * s <3 £ O S 8 0 Id TS -§ r a P~> 1 O -S> *§ CD to 0 £ 0 ►h S 3 c 3 o o a, a o o o o e* J a <9 -sg O :=T S C5 S s rX a ? fee o ^ £ O o r^J ~ .2 0 K 55 bX) S g O ct J-< Sh o o C+H o (D O ^ • Sh Ph X— CM §D HH P3 00 «! & CD o G^l O [>< o co OP 32 . Violet, tlic com; Blue „ EFFECTS OF JUXTAPOSITION. 14 HARMONY AND CONTRAST OF COLOURS. 38. It is evident that, all other things being equal, the modifications of contiguous colours will be so much the more marked, as the complementary colour C or C', which is added to each of them, differs more from them ; for the complementary C' which is added to the colour O, is identical with it, as the complementary C is identical with the colour P to which it is added : and the modi¬ fications of 0 and P will simply augment the intensity of their colours. But are there yet any two bodies known which present to the observer two pure colours perfectly complementary to each other 1 Certainly not; all those which are coloured by reflection reflect (7), besides white light, a great number of rays of various colours. We cannot instance a red body and a green body, or an orange and a blue, or an orange-yellow and an indigo , or a greenish-yellow and a violet, which reflect pure or mixed colours, absolutely complementary to each other. So that the juxtaposition of these colours produces only a simple augmentation of their intensity. Therefore if it is less easy to verify the law of contrast with respect to red and green, or orange and blue, tfcc., than with respect to those which are the object of the seventeen experi¬ ments just described (15), yet, upon applying it to the former, it will be seen that their colours acquire a most remarkable brilliancy, strength, and purity. This result, perfectly conformable to the law, may be easily under¬ stood : for example, an orange-coloured object reflects blue rays, as a blue object reflects orange rays (7). Hence, when a blue stripe is put in contact with an orange stripe, although it is admitted that the first appears to the eye to receive blue from the orange of the second, as this appears to receive orange from the blue of the blue stripe ; or what is the same thing, that the blue stripe appears to destroy the effect of the blue rays EFFECTS OF JUXTAPOSITION. 15 of the second stripe, as these appear to destroy the effect of the orange rays of the blue stripe—it is evident that the two colours so contrasted must purify each other, and become more intense. But the blue may incline to green or violet, and the orange to yellow or red ; that is to say, the modification may not only affect the in¬ tensity of the colour, but also its physical composition. However, if this latter effect take place, it is always much more feeble than the first. Besides, if you look several times at the same coloured stripes, you will see that the blue which at first had appeared to you green¬ ish will afterwards appear inclining to violet; and that the orange, which had appeared at first yellowish, will incline to red \ so that the phenomena of modification, as it affects the physical composition of colour, will not have the constancy of those which are the subject of the preceding seventeen observations (15). I now proceed to state the observations I have made on colours which are most nearly complementary to each other. Bed and Green. 39. Bed, the complementary of Green, being added to Bed, increases its intensity. Green, the complementary of Bed, being added to Green, increases its intensity. Such is the theoretical result, the experimental result entirely agrees with it. When we place a green, inclining more to yellow than to blue, side by side with, 1st, a slightly orange-red, 2nd, a slightly crimson-red, and 3rd, an intermediate red, and repeat our observations several times on each of these assemblages of colour, we shall observe different results; that is to say, in one case the red will appear more orange and the green yellower, and in another the red will appear more violet and the green 1G HARMONY AND CONTRAST OF COLOURS. bluer. We shall find also that the change may be attributed as much to a difference in the intensity of the light upon the colours as to fatigue of the eye. When we place a green, inclining rather to blue than to yellow, side by side with, 1st, a slightly orange-red, 2nd, a slightly crimson-red, and 3rd, an intermediate red, the results are the same as with the first green, but with this difference,—-that in the assemblage of bluisli- o-reen and of slightly crimson-red, observed several times, the green and the red appear almost constantly yellower than they are separately. A result very easily understood. Orange and Blue. 40. Blue, the complementary of Orange, being added to Blue, increases its intensity. Orange, the complementary of Blue, being added to Orange, increases its intensity. Upon repeating these observations with a deep blue and an orange which is not too red, the two colours appear commonly to become redder. Orange-Yellow and Indigo. 41. Orange-yellow, complementary of Indigo, being added to Yellow, increases its intensity. Indigo, complementary of Orange-yellow, being added to Indigo, increases its intensity. Greenish- Yellow and 1 iolet. 42. Greenish-yellow, the complementary of Violet, being added to Violet, increases its intensity. Violet, the complementary of Greenisli-yellow, being added to Violet, increases its intensity. The result of observation is almost always in con¬ formity with this law. EFFECTS OF JUXTAPOSITION'. 17 43. According to the law of the simultaneous contrast of colours, and the insensible gradation of modification, beginning at the contiguous edges of the colours in juxtaposition (11), we may show, by means of coloured circular spaces, the modifications which the principal colours induce in those which are contiguous to them. Place wafers, circular pieces of paper, or any other convenient material about an inch and a half in dia¬ meter, coloured red, green, orange, blue, greenish-yellow, \iolet, indigo, and orange-yellow, each separately upon a sheet of white paper; then tint the white paper around the circle with its complementary colour, gra¬ dually softening it off from the coloured circle, when it will be found that The Red circle tends to colour the surrounding space with its complementary Green. Red. Blue. Orange. Violet. Greenish-yellow. Orange-yellow. Indigo. These figures are designed to exhibit the effects of con¬ trast to those persons who, not having studied physical laws, are, notwithstanding, desirous of understanding these effects. tireen „ Orange „ Blue Greenish-yellow Violet „ Indigo „ Orange-yellow c 18 harmony and contrast of colours. CHAPTER IV. On the Juxtaposition of Coloured Surfaces with 11 kite. 44. When white bodies are viewed simultaneously with coloured bodies contiguous to them, they are sen¬ sibly modified. I confess that the modification is too feeble to be determined with absolute certainty while we are ignorant of the law of contrast; but, under - standing that, and knowing the modifications that white undergoes in connexion with certain colours, we shall not fail tu recognise this modification in special cases, pro¬ vided the colours opposed to the white be not too deep. Bed and White. 45, Green, complementary to Red, being added to White, the Red appears more brilliant and deeper. Orange and White. 4G. Blue, complementary to Orange, being added to White, the Orange appears more brilliant and deepei. Greenish-Yellow and TI kite. 47. Violet, complementary to Greenish-yellow, being added to White, the Yellow appears more brilliant and deeper ' Green and White. 48. Red, complementary to Green, being added to White, the Green appears more brilliant and deeper. Blue and White. 49. Orange, complementary to Blue, being added to White, the Blue appears more brilliant and deepei. COLOURS WITH WHITE. 19 Indigo and White. 50. Yellowish-orange, complementary to Indigo, being added to White, the Indigo appears more brilliant and deeper. Violet and White. 51. Yellowish-green, complementary to Yiolet, being added to White, the Yiolet appears more brilliant and deeper. Blade and White. 52. Black and white, which may be considered in some respects complementary to each other, become, conformably to the law of contrast of tone, more different than when seen separately. This results from the effect of the white light, which is reflected by the black (4), being more or less destroyed by the light of the white stripe. By an analogous action, the white heightens the tone of the colours to which it is contiguous. CHAPTER V. On the Juxtaposition of Coloured Bodies with Blade. 53. A elack surface being deeper than that which is contiguous to it, the contrast of tone tends to deepen it still more, while it tends to lower the tone of the con¬ tiguous colour ■ as on the other hand white, placed in juxtaposition with it, would heighten it. So much for contrast of tone. 54. Black surfaces reflect a small quantity of white light (4), and this falling upon the retina simultaneously with the coloured light of a contiguous body, it is evi¬ dent that the black surface must appear tinted with the c 2 20 HARMONY AND CONTRAST OF COLOURS. complementary of tire coloured light; but it will be a weak tint, since it is displayed upon a ground which has but a feeble power of reflecting light. So much for the contrast of colour. 55. The lowering of the tone of the colour contiguous to the black is constantly observed ; but a very remark¬ able fact is the weakening of the black itself, when the contiguous colour is deep, and of a nature to give a luminous complementary, as orange, orange-yellow, greenish-yellow, &c. Red and Blade. 56. Green, complementary to Red, renders the Black Reddish. Red appears clearer or less Brown, less Orange. Orange and Black. 57. Blue, complementary to Orange, renders the Black less Rusty or Bluer. Orange appears more brilliant and more Yellow, less Brown. Greenish- Yellow and Black. 58. Violet, complementary to Yellowish-green, renders the Black rather Violet. The Yellow is clearer, more Green perhaps ; and there are some kinds of Yellow r which are impoverished by their juxtaposition with Black. Green and Black. 59. Red, complementary to Green, being added to Black, renders the latter more Violet or Reddish. The Green inclines feebly to Yellow. Blue and Black. 60. Orange, complementary to Blue, being added to Black, the latter becomes clearer. The Blue is clearer, Greener perhaps. COLOURS WITH BLACK AXD GREY. 21 Indigo and Blach. 61. Orange-yellow, complementary to Indigo, being added to Black, brightens it much. Indigo is brightened. Violet and Black. 62. Greenish-yellow, complementary to Violet, being added to Black, brightens it. \ iolet is more brilliant, clearer, Redder perhaps. CHAPTER VI. On the Juxtaposition of Coloured Bodies with Grey. 63. As the brilliancy of the light reflected by white bodies is one of the principal causes which render the sight insensible to the modifications produced in white by the juxtaposition of coloured bodies ; and, on the other hand, as the feeble light reflected from black bodies is unfavourable to our perception of the modifications which they sustain from the proximity of coloured bodies, especially when the complementary of the colour of these bodies is but slightly luminous, it may be conceived that grey bodies, judiciously selected with regard to their depth of tone, would, by contiguity to coloured bodies, exhibit the phenomena of contrast of colour in a more striking manner than either black or white bodies would. Red and Grey. 64. Grey appears Greenish by receiving the influence of the complementary of Red. Red appears purer, less Orange perhaps. 22 HARMONY AND CONTRAST OF COLOURS. Orange and Grey. G5. Grey appears Bluer by receiving the influence of the complementary of Orange. Orange appears purer, more brilliant, Mellower pei- haps. Yellow and Grey. 66. Grey appears to incline to Violet by receiving the influence of the complementary of Yellow. Yellow appears more brilliant, and yet less Green. Green and Grey. 67. Grey appears to incline to Red by receiving the influence of the complementary of Green. Green appears more brilliant, Yellower perhaps. Blue and Grey. 68. Grey appears to incline to Orange by receiving the influence of the complementary of Blue. Blue appears more brilliant, Greener perhaps. Indigo and Grey. 69. Grey appears to incline to Orange by receiving the influence of the complementary of Blue. Blue appears more brilliant, Greener perhaps. Violet and Grey. 70. Grey appears yellowish by receiving the influence of the complementary of Violet. Violet appears fresher, less dull. 70a The grey, which was the subject of the above experiments, was as free as possible from every colouring matter foreign to black; it belonged to the scale of normal black (see Part II, 164)—that is to say, it re- COLOURS WITH BLACK, ETC. .suited from a mixture of tlie purest possible black and white materials. By juxtaposition with white, it ap¬ peared deepei', aud the white appeared more pure ; while by juxtaposition with black, it appeared lighter and more rusty, and the black appeared deeper. 705. One result of the complementaries of colours in juxtaposition with grey being more perceptible than when these colours are juxtaposed with white or black, is, that if instead of a normal grey, we juxtapose a grey, tinted either with red, orange, ydlovj, &c., these tints will be greatly heightened by the complementaries added to them. For example, a bluish grey will receive a very perceptible increase of blue from its proximity to orange, and a yellowish-grey will take a perceptible green tint from the same proximity. Note .—The chemical nature of coloured, substances has no influence upon the phenomena of simultaneous contrast. 71. The chemical nature of coloured bodies in juxta¬ position has no influence upon the modifications of their colours. Whatever may happen to be the chemical com¬ position of the coloured bodies, provided they be iden¬ tical to the sight, they yield the same results. I need only cite the following examples :—Indigo, Prussian- blue, cobalt, ultramarine, as nearly alike as possible, gave the same sort of modification ; orange prepared from red lead, annotto, or a mixture of woad and madder, caused the same modification of the colours to which they were adjacent. 24 HARMONY AND CONTRAST OF COLOURS. CHAPTER VII. Oil ilie Juxtaposition of Coloured Bodies belonging to the Colours of the same Group of Coloured Bays. 72. Whenever there is a great difference between two contiguous colours, the difference becomes still more appreciable by putting the same colour successi\ ely in juxtaposition with the various colours belonging to the same group. For example, orange and red. Orange being placed beside scarlet-red, pure red and crimson-red, it will be seen that the red acquires a purple and the orange a yellow tint. Violet being placed beside scarlet-red, pure red and crimson-red, gives analogous results : the violet always appears bluer, and the red yellower or less purple. 73. These observations explain why we obtain results in accordance with the formula, even when such coloured substances are used as are far from exhibiting pure colours, namely, stained papers or stuffs. 74. The juxtaposition of coloured stripes is a means of demonstrating the difficulty of determining the types of pure colours by common pigments ; at least, if we do not take into consideration the law of simultaneous con¬ trast. For instance— 1. Place red in contact with orange-red; the first will appear purple and the second yellower, as above ; but if the first red be placed beside purplish-red, the latter will appear bluish, and the former more yellow or orange; so that the same red will be purple in one case and orange in the other 2 . Place yellow beside orange-yellow, the former COLOURS OF THE SAME GROUP. 25 will appear greenish and the latter redder ; but if you put the first yellow beside a greenish-yellow, the last ■will appear greener, and the yellow more orange ; so that the same yellow Mill incline to green in one case, and to orange in the other. 3 . Place blue beside greenish-blue, the former will incline to violet, and the second will appear yellower. Put the same blue beside a violet-blue, the former will incline to green, and the second will appear redder ; so that the same blue will be violet in one case and greenish in the other. 75. Hence we see that the colours which painters term simple—red, yellow, and blue—pass insensibly by juxtaposition into the condition of compound colours, since the same red is purple or orange ; the same yellow is orange or green ; and the same blue is green or violet. CHAPTER VIII. On the Application of the Law of Contrast to the Hypo¬ thesis that Red, Yellow, and Blue are the only Primary Colours; and that Orange, Green, Indigo, and Violet are Secondary or Composite Colours. 76. The experiments to which I have just applied the principle of the modification which colours undergo by juxtaposition, and the explanation consequent upon the manner in which white light has been considered, arc also clearly explained in the language of painters and dyers, who admit of only three primary colours—red, yellow, and blue. As there are persons who, while they hold this opinion, desire, notwithstanding, to give a reason for the phenomena resulting from the juxtaposition 26 HARMONY AND CONTRAST OF COLOURS. of colours, I will explain them in accordance with this language ; and, for greater clearness, I make five groups of juxtaposed colours, beginning with those which include the observations to which the preceding law is most easily applied. I shall presume that orange is composed of red and yellow, green of yellow and blue, indigo and violet of red and blue. First Group. — Two Secondary Colours having a Simple Colour as a Common Element. It is very easy to verify the law when we look at two colours which form part of the group : we see that by their reciprocal influence they lose more or less of the colour which is common to them. It is evident that they become more unlike each other in proportion to this loss. 1. Orange and Green. —-These colours having the ele¬ ment yellow in common, lose it by juxtaposition. The orange appears redder, and the green bluer. 2 . Orange and Indigo. —These colours having the clement red in common, lose it by juxtaposition. The orange appears yellower, and the indigo greener. 3 . Orange and Violet.-— Like the preceding. 4 . Green and Indigo. —These colours having the ele¬ ment blue in common, lose it by juxtaposition. The orange appears yellower , and the indigo bluer. 5 . Green and Violet. —Like the preceding. Second Group.—-A Compound Colour, and a Simple Colour, which is found in the Compound. 1 . Orange and Red- —The orange loses red, and ap¬ pears yellower \ the red becomes bluer, to differ as much as possible from the orange. 2 , Violet and Red. —The violet loses red, and ap- APPLICATIONS OF THE LAW. 27 pears bluer; the red becomes yellower, to differ as much as possible from the violet. 3 . Indigo and Red. —Like the preceding. 4 . Orange and Yellow.— The orange loses yellow, and appeal’s redder; the yellow becomes bluer, to differ as much as possible from the orange. 5 . Green and Yellow. —The green loses yellow, and appears bluer ; the yellow becomes redder, to differ more from the green. 6. Green and Blue.— The green loses blue, and ap¬ pears yellower; the blue becomes redder, to differ as much as possible from the green. 7 . Violet and Blue. —The violet loses blue, and ap¬ pears redder ; the blue must become yellower to differ as much as possible from the violet. 8 . Indigo and Blue.- —Like the two preceding. Third Group.— -IFwo Simple Colours. 1 . Red and Yelloiv. —Red in losing yellow appears bluer; and the yellow losing red appears bluer ; or, in other words, the red inclines to purple, and the yellow to green. 2 . Red and Blue. —The red in losing blue appears yellower ; and the blue losing red appears yellower; or, in other words, the red inclines to orange, and the blue to green. 3 . Yellow and Blue.- —The yellow in losing blue ap¬ pears redder; and the blue losing yellow appears more violet; or, in other words, the yellow inclines to orange, and the blue to violet. Fourth Group. — Two Compound Colours consisting of the same Simple Colours. Indigo and Violet. —As indigo differs from violet only 28 HARMONY AND CONTRAST OF COLOURS. in containing more blue in proportion to red, it follows that the difference will be greatest when the indigo loses red and inclines to greenish blue, while the violet, by gaining red, inclines toward that colour. It is clear that, if the violet lost red, or if the indigo acquired it, the two colours would approximate ; but, as they differ from each other, the first effect ensues. We may further explain the preceding phenomena by considering indigo relatively to violet, as blue ; then it will lose its blue, which is common to both colours, and incline to green ; while the violet, also losing its blue, will appear redder. Fifth Group. —A Compound Colour, and a Simple Colour, which is not found in the Compound. i. Orange and Blue. 2 . Green and Orange. 3 . Violet and Greenish Yellow. Upon the hypothesis that orange, green, and violet are compound colours, and that red, blue, and yellow are simple, it follows that in opposing them in the order in which they are reciprocally complementary, and supposing also that the colours so juxtaposed are entirely free from any foreign colour, there appears no reason for the compound colour losing one of its ele¬ ments rather than another, or for the simple colour being unlike one of the elementary colours rather than another. For instance, in the juxtaposition of green and red, we see no reason why green should pass into blue rather than into yellow, or why the red should in¬ cline to blue rather than to yellow. VARIOUS KINDS OF CONTRAST. 29 SECTION II. ON THE DISTINCTION BETWEEN SIMULTANEOUS, SUCCES¬ SIVE, AND MIXED CONTRAST OF COLOURS, AND ON THE CONNEXION BETWEEN THE EXPERIMENTS MADE BY THE AUTHOR, AND THOSE PREVIOUSLY MADE BY OTHER OBSERVERS. DISTINCTION BETWEEN SIMULTANEOUS SUCCESSIVE, AND MIXED CONTRAST OF COLOURS. 77. Before speaking of the relation of my experi¬ ments to those made by others on the contrast of colours, we must distinguish three classes of contrast. The first includes those relating to the contrast which I term simultaneous; the second to that which I term successive ; and the third to that which I term mixed. 78. Simultaneous contrast of colours includes the phenomena of modification that objects variously coloured seem to undergo in physical composition, and in the depth of tone of their respective colours, when seen at the same time. 79. Successive contrast of colours includes the pheno¬ mena observed when the eyes having looked for some time at one or more coloured objects, perceive, after haviim ceased to look at them, images of those objects, presenting the colour complementary to that of the actual object. ° 80. This distinction also facilitates the understand¬ ing of the phenomena which may be called mixed con¬ trast; for, the retina having seen a certain colour for some time, has an aptitude to see for a further time the complementary of that colour, as well as any new colour presented by an external object; the sensation perceived being the result of this new colour, and the complementary of the first. 81. The following is a simple mode of observing mixed contrast: —Having closed one eye, the right for example, look steadily with the left at a sheet of paper 30 HARMONY AND CONTRAST OF COLOURS. of a colour A; when this colour seems to become dull, look immediately at a sheet of paper of the colour B, the eye then has the impression produced by the mix¬ ture of this colour B with the complementary (C) of the colour A. .... 82. To be convinced of this mixed sensation, it is only necessary to shnt the left eye, and to look at the colour B with the right eye ; when the sensation per¬ ceived is not only that of the colour B, but it may appear modified in the contrary way to that of the mixed sensation C + B, or what is the same, it appears to be rather A + B. 83. Upon shutting the right eye, and looking again at the colour B with the left eye, and that many times in succession, different sensations are successively per¬ ceived, but more and more feebly, until at length the left eye returns to its normal state. 84. I advise any person who thinks that one of his eyes is more able to perceive colours than the other, to look at a dheet of paper alternately with the right and left eye ; if the sensations of each are identical, he may conclude that he has deceived himself. And even if the sensations be different, the experiment should be several times repeated successively, for the difference observed in a single experiment might be occasioned by one of the eyes having been previously modified or fatigued. 85. This practice appears to me especially useful to painters. I now give some examples of mixed contrast. 86 . The left eye, having looked for some time at red, has an aptitude to see afterwards green, the com¬ plementary of red. If then it be attracted by yellow, it perceives a sensation resulting from the mixture of green and yellow. The left eye being shut, and the MIXED CONTRAST. 31 right eye, which has not been modified by the sight of red, being opened, it sees yellow, and it is possible that 87. If the left eye and had after¬ the latter ivould had first seen wards seen have seemed Yellow Red Violet. 88 . Red Blue Greenish. 89. Blue Red Orange-red. 90. Yellow Blue Blue-violet. 91. Blue Yellow Orange-yellow. 92. Red Orange Yellow. 93. Orange Red Red-violet. 94. Red Violet Deep blue. 95. Violet Red Orange-red. 96. Yellow Orange Red. 97. Orange Yellow Greenish-yellow. 98. Yellow Green Bluish-green. 99. Green Yellow Orange-yellow. 100. Blue Green Yellow-green. 101. Green Blue Blue-violet. 102. Blue Violet Reddish-violet. 103. Violet Blue Greenish-blue. 104. Orange Green Bluish-green. 105. Green Orange Reddish-orange. 106. Orange Violet Bluish-violet. 107. Violet Orange Yellowish-orange. 108. Green Violet Red-violet. 109. Violet Green Yellow-green. 110. Red Green Bluer. 111. Green Red Tinted-violet. 112. Yellow Violet A little bluer. 113. Violet Yellow Greenish. 114. Blue Orange Yellower. 115. Orange Blue More violet. 32 HARMONY AND CONTRAST OF COLOURS. 11 G. I should observe that all these colours, at least to my eyes, did not undergo equally intense or equally continuous modifications. For instance, the modifica¬ tion produced by the successive view of yellow and violet, or of violet and yellow, is stronger and more durable than that produced by the successive view of blue and orange, and still more thair that of orange and blue. The modification produced by the successive view of red and green, of green and led, is but slight, and not enduring. I may also add that the depth of tone exercises some influence on the modification ] for, if after looking at orange, we look at dark blue, the latter will appear Greenish rather than violet, a result contrary to that afforded by a light blue. 117. I have thought it the more necessary to men¬ tion under a special name the phenomenon which I call mixed contrast, as it explains certain facts remaiked by dealers in coloured fabrics, as well as the inconvenience felt by painters, who, wishing to produce an exact imita¬ tion of their models, look at them so long as to be unable to perceive their tones and modifications. X will men tion two facts which have been communicated to me by manufacturers, referring the reader to Part II. for the application of the study of mixed contrast to painting. 118. First Fact. When a purchaser has looked a long time at a yellow cloth, and he is then shown an orange, orange-red, or scarlet one, he finds it dull, and judges it to be a dark or crimson-red ; for, in fact, the retina affected by the yellow has a tendency to see violet ; and hence all the yellow of the orange colour disappears, and the eye sees it as a red, or a red inclining to violet. 119. Second Fact. If there be presented to a pur- MIXED CONTRAST. cliaser, one after another, fourteen pieces of a red fabric, he judges the six or seven last pieces to be less beautiful than the first, although they may be all identical. What is the reason of this false judgment ? It is, that the eyes which have seen six or eight red pieces in succes¬ sion, are in the same condition as if they had looked steadily for the same length of time at a single red stuff, —having a tendency to see the complementary of red, that is green. This tendency necessarily enfeebles the brilliancy of the red of the last pieces. The dealer, therefore, that he may not be a sufferer from the fatigued eyes of his customer, after showing him a few red pieces, should present some green ones, to restore the eyes to their normal state. If the view of the green were suffi¬ ciently prolonged to pass the normal state, the eyes would acquire a tendency to see red, and then the pieces seen last would appear more beautiful than the rest. D 34 HARMONY AND CONTRAST OF COLOURS. PAST THE SECOND. ON THE APPLICATION OF THE LAW OF SIMULTANEOUS CONTRAST OF COLOURS. INTRODUCTION. 120. Before entering into the details of these applica¬ tions, I think it necessary to offer some considerations which will enable me to establish some propositions or principles, to which I shall have frequent occasion to refer. I propose to give- _ 121. 1. Definitions of several expressions applicable to colours and their modifications. 2. The means of representing and defining colours and then- modifications by the aid of diagrams. 3. A classification of the har¬ monies of colours. 4. A view of some arrangements of the primary colours 'with white, black, and giey. SECTION I. Definition of the words Tones, Scales, and Hues. 122. The words Tones and Hues recur continually, both in common language and in that of artists; yet they are not so well defined as to be free from am¬ biguity, or to be well understood. 123. The word tone of a colour will be employed exclusively to designate the various modifications which that colour, in its greatest intensity, is capable of receiv¬ ing from white, which lowers its tone, or of black, which heightens it. 124. The word scale will be applied to the assem- DEFINITIONS. O-J blage of tones of the same colour, thus modified. The pure colour is the normal tone of the scale, if the normal tone does not belong to a broken or reduced scale— i.e., to a scale, of which all the tones are made dull with black (153). 125. The word hue will be applied exclusively to the modifications which a colour receives from the addition of a small quantity of another. We shall speak, for example, of the tones of the blue scale, the tones of the red scale, etc. We say the hues of blue to designate all the scales whose colours, still remaining blue, yet differ from pure blue ; each hue comprehending the tones which constitute a scale more or less allied to the blue scale. 126. I have defined the tones of a colour to be the various modifications, which that colour at its maximum of intensity is capable of receiving from black and white ; it must be observed that the condition “ maximum of in¬ tensity for receiving black,” Is absolutely essential to this definition j for if black be added to a tone below the maximum, it would pass into another scale. Artists distinguish colours as pure, broken, reduced, grey, or dull. 127. Pure colours are those termed simple, red, yellow, blue, and those which result from their binary compounds, orange, green, violet, and their hues. (153.) Broken colours are the pure colours mixed with black, from the tone of the lightest to the deepest. According to these definitions, it is evident that in all the scales of simple and binary colours, the tones which are above the pure colour are brolcen tones. 128. Artists, and especially painters and dyers, admit that the mixture of three primary colours, in a certain d 2 3G HARMONY AND CONTRAST OF COLOURS. proportion, gives black; lienee, when these three colours are so mixed that two predominate, black Avill result, formed from the union of the whole of the colour, which is in small quantity, within suitable pro¬ portions of the two predominant colours. For example, if blue be mixed with red and yellow, a little black is produced, which reduces or breaks the orange. 129. We must remember that the primary colours of painters are not those of the prismatic spectrum, but substances employed by them, as red, yellow, and blue colours. SECTION II. Of Diagrams designed to Represent and Define Colours and their Modifications. 130. Various contrivances have been proposed under the titles of Tables, Scales, Colour-Circles, Chromato¬ meters, &c., for representing either by numbers or a rational nomenclature, colours and their modifications. They arc generally founded on these three propositions : _i There are three primary colours. 2. Equal portions of these colours being mixed, produce pure secondary colours. 3. Equal portions of the three primary colours produce black. 131 But i. We know of no substance which exhibits mire colour; that is, which reflects only one kind of coloured rays, whether pure red, pure yellow, or pure blue. 2 Since it is impossible to procure pure colouiing matters, how can it be said that orange, green, and violet are composed of two simple colours mixed in equal proportions'! Or that black consists of a mixture of equal parts of three simple colours 1 GREEN CHROMATIC DIAGRAM. CHROMATIC DIAGRAMS. 37 These chromatic tables, &c., point out mixtures which do not produce the results deducible from their pre¬ tended principles. 132. But most of the blue, red, and yellow colours with which we are acquainted, give, by their binary compounds, violet, green, and orange inferior in bril¬ liancy to the natural violet, green and orange colours of objects. This result would be explained by ad¬ mitting that colours mixed two by two, reflect at least two kinds of coloured rays ; and that where there is any mixture of colours which reflect separately red, yellow, and blue, there is produced a certain amount of black which reduces the brilliancy of the mixture. 133. Conformably with this view, the violet, green, and orange colours which result from a mixture of coloured matters, are most brilliant when the re¬ spective colours of these materials approach each other. For example, a mixture of blue and red in¬ clines more to violet than a mixture of blue and yellow inclines to green, and that of red and yellow inclines still more to orange. 131. In order to represent all the modifications that I have called tones and hues of colours, as well as the relations which exist between those that are comple¬ mentary to each other, I have devised the following diagram :—From a centre, c, I describe two circum¬ ferences, yy' (fig. 4). I divide each of these by means of three rays, ca, cl>, cd, into arcs of 120 degrees each. I divide the portion of each ray comprised between the two circles yy' into twenty parts, which represent as many tones of the colours red, yellow, and blue. 135. In each of the scales of these three colours there 38 HARMONY AND CONTRAST OF COLOURS. is one tone, which, when pure, represents the colour of the scale to which it relates. I therefore call it the normal tone of that scale. If we represent a unit of sur¬ face s, entirely covered by the pigment which reflects the normal colour, and if we suppose that this colouring matter is equally distributed over the surface a 1, we shall represent the tones superior to the normal tone by the unit of surface covered with 1 of the normal colour, plus the quantities of black increasing with the number of tones ; and we shall represent the inferior tones by the unit of surface covered with a fraction of the quantity 1, constituting the normal tone, mixed with (—) quantities of black, as the tone has a less elevated number. If the tone 15 of the red scale be the normal tone, the normal tone of the yellow scale will have a lower number, while the normal tone of the blue scale will have a higher number. This depends upon the inequality of the clearness or brilliancy of the colours. 136. If each arc of 120° be divided into two of 60°, and if radii pass through the points of division, be¬ ginning at y, there will be represented twenty tones of the orange, green, and violet scales, the colours which are at the extremities of each diameter being comple¬ mentary to one another. Each arc of 60° might be di¬ vided into arcs of 30°, and thus would be obtained radii representing twenty tones of scales, which I shall call orange-red, orange-yellow, greenish-yellow, greenish-blue, bluish-violet, and violet-red. 137. By dividing each arc into five, for example, by means of five radii, which I divide into twenty parts each, beginning at the circumference y, I shall obtain sixty new scales. CONSTRUCTION OF CHROMATIC DIAGRAM. 39 138. Beginning with red, I designate them as follows :— a Red e Yellow i Blue 1 Red 1 Yellow 1 Blue 2 Red 2 Yellow 2 Blue 3 Red 3 Yellow 3 Blue 4 Red 4 Yellow 4 Blue 5 Red 5 Yellow 5 Blue 139. b Red-orange f Yellow-green Jc Blue-violet 1 Red-orange 1 Yellow-green 1 Blue-violet 2 Red-orange 2 Yellow-green 2 Blue-violet 3 Red-orange 3 Yellow-green 3 Blue-violet 4 Red-orange 4 Yellow-green 4 Blue-violet 5 Red-orange 5 Yellow-green 5 Blue-violet 140. c Orange g Green l Violet 1 Orange 1 Green 1 Violet 2 Orange 2 Green 2 Violet 3 Orange 3 Green 3 Violet 4 Orange 4 Green 4 Violet 5 Orange 5 Green 5 Violet 141. d Orange-yellow h Green-blue m Violet-red 1 Orange-yellow 1 Green-blue 1 Violet-red 2 Orange-yellow 2 Green-blue 2 Violet-red 3 Orange-yellow 3 Green-blue 3 Violet-red 4 Orange-yellow 4 Green-blue 4 Violet-red 5 Orange-yellow 5 Green-blue 5 Violet-red I attach no importance to this nomenclature; I employ it only as the simplest to distinguish the sixty-two scales just described. The number may be increased indefi¬ nitely, by inserting as many as we choose between the above. 142. Let us now represent the gradations of each colour in the scales of the circle by the addition to it of black, progressively increasing till it becomes pure black. 40 HARMONY AND CONTRAST OF COLOURS. Imagine a quadrant whose radius is equal to that of the circle, and arranged so as to turn upon an axis perpendi¬ cular to the plane of the circle. Divide this quadrant, 1st, by concentric arcs y y', which coincide with the circumfe¬ rences of the circle denotedby the same letters; 2nd, by ten radii, 1,2,3, 4, 5, 6, 7, 8, 9,10. Divide each of these radii into t wenty parts, representing twenty tones, correspond¬ ing to the tones of the scales represented on the circle. 143. I suppose that the tenth radius comprises the gradations of normal black, which envelopes the half¬ circle described by the movement of the quadrant upon its axis ; this black mixed in decreasing quantities, with increasing quantities of white, gives the twenty tones of normal grey, and ends by being lost in the white situated above the tone 1. I suppose, further, that the normal tone of each of the scales taken upon each of the radii of the quadrant 1, 2, 3, 4, 5, 6, 7, S, 9, is formed of the mixture of black with the colour of any of the scales that the circle contains, and in such a pro¬ portion that the normal tone 15 of that scale is repre¬ sented by the unit of surface covered with 1, or of red. 144. The tone 15 of the scale of the 1st Radius = 2nd „ = 3rd „ 4th „ = 5th „ = 6th „ = 7 th „ = 8 th „ 9th To 8 TT 7 To e To TTT 4 TO" 3 TO o To 1 1 0 of Pted TO 2 TTT 3 nr 4 TTT 5 To" 6 1 0 7 1 0 8 1 0 f) TH of Black. These proportions relate to the effect of the mixtures upon the eye, and not to the material quantity of the red and black substances. USES OF THE CHROMATIC DIAGRAM. 41 145. We see then—-1. That each of these tones, 15, composed of colour and black, reduced by white and deepened by black, gives a scale of twenty tones, so much the more broken as they are nearer the scale of normal black. 2. That the quadrant, by its movement upon the axis of the circle, represents the scales of every colour except red, broken by black. These broken scales are equidistant, and are formed of equidistant tones. 3. That all the colours are thus contained in a half-circle, whose circular plan comprehends the pure colours ; the central radius, black; and the intermediate space the pure colours, broken by the various propor¬ tions of black. 146. The semicircular diagram, as just described, thus represents the lowering of pure colours by white, and their gradation by black ; their modifications by their mutual mixtures, the modification of hues, and the modification of breaking ( rabat ). We will presently inquire into the possibility of realizing it by means of coloured materials. 147. We have presumed—1. That the normal tone of each of the scales comprised in the half-circle is as pure as possible. 2. That the tones bearing the same number in all the scales,—both those of the pure colours and those of the broken colours,—are, to the sight, of equal depth. 3. That if three tones, of the same number, be taken in three consecutive scales, the tone of the intermediate scale is the mean between the colours of the extreme scales. It is thus easy to explain the modifications of a pure colour commencing with its normal tone. 148. These modifications are so produced that— i. The Pure Colour never leaves its Scale. —The modi¬ fication is in the direction of the radius of the circle— 42 HARMONY AND CONTRAST OF COLOURS. proceeding from the normal tone towards the centre, it gains white ; while proceeding from the normal tone towards the circumference, it gains black. 149. 2 . The Pure Colour leaves its Scale by the addition of Black .—In this case the various scales comprised in the quadrant perpendicular to the circle, begin at the normal tone of one of the pure scales of the circle with which the quadrant coincides. This normal tone, resulting from a quantity of colour represented by unity, covering a unit of surface s, the normal tones of the quadrant result from the mixture of black and a fraction of unity of the colour. These mixtures constitute broken colours, each covering a unit of surface s, and are of the same depth as the normal tone of the pure colour. The fraction of the quantity of colour is, in the broken normal tones, so much less, as the scales, to which these tones belong, approximate to the vertical axis of the semicircle. Besides, each normal tone of the scales of the quadrant is modified, like the normal tones of the scales of the circle, by increasing quantities of white towards the centre, and of increasing quantities of black towards the circumference. 150- 3 . A Pure Colour is modified by the addition of another Pure Colour.—In this case hues are formed so much more resembling each other, as the quantities of the second colour are smaller. These modifications are made circularly, so that the tones retain their num¬ bers. Thus admitting, with painters and dyers, that there are only three primary colours, and that by com¬ bining these two by two, we obtain all the pure complex colours; and by combining them in threes, all the broken USES OF THE CHROMATIC DIAGRAM. 43 colours ; we find that it is possible to represent by this hypothesis, all the modifications of colours. 151. Another advantage of this construction is that of giving to all artists who may make applications of the law of simple contrast, the complementaries of ail the pure colours ) since the colours of the circular plan ■which are found at the extremities of the same diameter are complementary to each other. For example, not only are red and green, blue and orange, yellow and ■violet on the same diameter, but it is so with orange-red and bluish-green, and yellowish-green and violet-red , of red No. 1 and of green No. 1 ; so that all the colours opposed to each other are mutually complementary. 152. The complementary of a colour contiguous to another being once known, it is easy, according to the principles of combination, to determine the modification that the second must receive from the first; since this modification is the result of the mixture of the comple¬ mentary with the contiguous colour. In fact, if there is no difficulty when the result is that of the non-com- plementary mixture with a simple colour, red, yellow, and blue, with a binary colour, orange, green, violet (using the language of painters, 7 6), there is no greater difficulty when the result is that of the mixture of two binary colours. For the complementary being much less intense than the colour with which it is mixed, the result will be found by subtracting from the last binary colour the portion of its simple colour, which with the complementary forms white, or in other words, neu¬ tralises it. 153. Examples. —1. Orange being added as a comple¬ mentary to green, neutralises a portion of its blue, and con¬ sequently makes it appear less blue or more yellow. 44 HARMONY AND CONTRAST OF COLOURS. 2. Orange being added as complementary to violet, neutralises a portion of its blue, and consequently makes it appear less blue or more red. 3. Green being added as complementary to violet, neutralises a portion of its red, and consequently makes it appear less red or more blue. 154. These three examples are easily explained by sub¬ tracting from the binary colour a portion of its simple colour which is identical with that contiguous to it. Thus : — 1 . Blue subtracted fromGreen,makes it appear moreYellow. 2. Blue „ „ Violet „ „ P^ed. 3. Bed „ „ Violet „ „ Blue. 155. To put the diagram into practice we must adopt invariable types of colour, either in the solar spectrum, or in polarized light, or coloured rings, or colours deve¬ loped in a constant manner, by any process whatever; then imitate them with the utmost fidelity, by means of colouring matters which should be applied to the circular plan of our chromatic diagram. These types must be sufficiently numerous to repro¬ duce the principal colours, in order that a practised eye may without difficulty insert all the tones of the same scale and all the hues of which types are wanting. In fact the diagram thus established, should present terms so near that the various colours of the natural bodies might be referred to them. 156. t. That it represents all the Modifications result¬ ing from the Mixture of Colours. — Thus any colour lowered by white and deepened with black may, retain¬ ing its place in the scale, give rise to an infinite variety of tones ; infinite, inasmuch as an unlimited number may be inserted from tone 1 to tone 20. USES OF THE CHROMATIC DIAGRAM. 45 157. 2 . Pure colours, by tbeir mutual modifications, m ay produce an infinite variety of bues; for between two adjacent bues we may insert as many as we desire. 158. 3 . Tbe normal tone of a pure colour represented by a quantity equal to 1 , covering tbe unit of surface, is tbe commencement of tbe normal tones and scales pro¬ ceeding towards black ; these normal tones being repre¬ sented by black and a quantity of colour less than unity, constituting the mixtures which cover a unit of surface s, and colour it of a tone which has the same number as the normal tone of the pure scale to which it relates. It is understood that in proceeding from this tone to the corresponding tone of normal black, we may insert an unlimited number of mixtures of colour and black. 159. The modifications of colours, thus indicated by the diagram, render it extremely easy to understand the definitions given above (123) of the words, scales, tones, hues, pure and broken colours. 160. 2 . Jt affords the means of knowing the comple- mentaries of every colour, since the names vrritten at the two extremities of any one diameter indicate the colours complementary to each other. 161. Examples. — a. Suppose it be required to know the mutual influence of blue and yellorw; at one extremity of a diameter we read the word blue , and at its opposite end, the word orange; showing that blue tends to give orange to yellow. Again, at the end of another diameter we read the word yellow, and at its opposite, the word violet; by which we see that yellow tends to give violet to blue. 162. b. Suppose green and blue be contiguous; at one extremity of a diameter we read the word green, and at its opposite end, red; showing that green tending to 46 HARMONY AND CONTRAST OF COLOURS. give red to blue, must render it more violet. Again, at one end of a diameter we read the word blue, and at its opposite end, orange. But wbat arises from the mixture of green and orange ? The orange will tend to neutralize its complementary, blue, in the green; and as it is always too feeble to neutralize all the blue, its influence will be limited to neutralizing a portion of it: whence it results that green, contiguous to blue, will appear more yellow than it really is. 163. c. Let green and yellow be contiguous, we shall see in like manner that the green, by imparting red to the yellow, will render it orange; and that violet, the complementary of yellow, by neutralizing some yellow in the green, will make the green appear bluer, or less yellow. 164. 3 . A third advantage of this diagram, which dis- tinguishes it from other chromatic diagrams, is, that it affords the -preceding advantages, without being coloured. 165. 4 . A fourth advantage is that of its manifesting to all artists tvho use coloured materials, of a given size, to attract the eye, especially the workers of tapestry, carpets and the like, the relation of number which must exist between the tones of the various scales which they work together. SECTION III. Harmony of Colours. 166. The eye has an undoubted pleasure in seeing colours, independently of the design and every other quality of the object which displays them. A suitable example to demonstrate this, is the wainscoting of an apartment in one or more flat tints which only attract HARMONY OF COLOURS. 47 the eyes and affect them more or less agreeably, as the colours are well or badly chosen. 167. First Case. Agreeable Colour. —Every one, whose eyes are well organized, has derived pleasure from look¬ ing at the coloured rays transmitted through a coloured glass, whether it be red, orange, yellow, green, blue, or violet. 168. Second Case. Different Tones of the same Scale of Colour. — The simultaneous view of the series of tones of the same scale, which commences with white and ends with dark brown, gives undoubtedly an agree¬ able sensation, especially if the tones have equal and sufficiently numerous intervals, — for example, from eighteen to thirty. 169. Third Case. View of Different Colours, belong¬ ing to adjacent Scales, assorted conformably to Contrast .—- The simultaneous view of different colours, belonging to scales more or less allied to each other, may be agree¬ able ; but the assortment of scales producing this effect is very difficult to obtain, because the more nearly the scales approach, the more frequently it happens that one of the colours injures that which is adjacent to it, and even both are reciprocally injurious. The painter may, however, take advantage of this harmony, by sacrificing one of the colours, which he subdues, to make the other more brilliant. 170. Fourth Case. View of very different Colours, beloriging to very distant Scales, arranged conformably to Contrast. —The simultaneous view of complementary colours, or of binary assemblages of colours, which, without being complementary, are yet very different, is also an undoubtedly agreeable sensation. 171. Fifth Case. View of various Colours, assorted 48 HARMONY AND CONTRAST OF COLOURS. more or less according to the Law of Contrast, being seen through a glass of a colour not deep enough to allow all the colours peculiar to the glass to be visible, afford a spectacle which is not without its charm, and which is placed evidently between that produced by the tones of the same scale, and that which is produced by various colours; for it is evident, that if the glass were of a deeper colour, it would cause objects to be seen of the colour peculiar to it. 172. Hence we infer that there are six distinct har¬ monies of colour, comprised in two species. First Species—Harmonies of Analogy. — 1. The harmony of scale, produced by the simultaneous view of different tones of the same scale, more or less approxi¬ mating. 2. The harmony of hues, produced by the simultaneous view of tones of the same, or nearly of the same depth, belonging to neighbouring scales. 3. The harmony of a dominant coloured light, produced by the simultaneous view of various colours assorted according to the law of contrast, but one of them predominating, as would result from the view of these colours through a slightly-coloured glass. 173. Second Species—Harmonies of Contrast.— 1. The harmony of contrast of scale, produced by the simulta¬ neous view of two very distant tones of the same scale. 2. The harmony of contrast of hues, produced by the simultaneous view of tones of different depths, belonging to neighbouring scales. 3. The harmony of contrast of colours, produced by the simultaneous view of colours, belonging to very distant scales, assorted according to the law of contrast. The difference in the depth of the adjacent tones may further augment the contrast of colours. ASSORTMENTS. 49 SECTION IY. Assortments of Red,Orange, Yellow, Green, Blue , Violet with White, Black,, and Grey. 174. It will not be useless to the object of this work to introduce some observations relative to the degree of beauty of certain arrangements of the primitive colours with black, white, and grey. But I cannot too strongly insist upon the fact, that they are not given as a rigorous deduction from scientific rules, for they are only the expression of my particular taste ; yet I hope that many classes of artists, especially dressmakers, decorators of all kinds, designers of patterns for woven fabrics, paper- hangings, etc., will find advantage in consulting them. 1 / 5. The ground, as well as the interval between the colours, having influence upon their effect, all my obser- Tat ' ons were made with white, black, grey, and coloured circles, - r \ of an inch in diameter, separated by intervals of y, 7 of an inch; thirteen circles arranged in a straight line forming a series. 170. The series designed to show the effect of white were on a ground of normal grey; those to show the effect of black and of grey were upon a white ground, slightly tinged with grey. It is necessary to remark that the coloured circles placed apart, were upon black grounds, which must have exercised some influence. 17/. The colours which have been under my notice are red, orange, yellow, green, blue, violet. Their differ¬ ences 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 E 50 HARMONY AND CONTRAST OF COLOURS. luminous colours, and tlie 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 em¬ ployed as luminous colours. Article I. Colours with White. A. Binary Assortments. 178. All the primary colours gain by their juxta¬ position 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 comple- COLOURS WITH WHITE. 51 inemary colours. X -shall tliereforc only describe tbe effect of white interposed between tbe binary comple¬ mentary assortments, or between each of the comple¬ mentary colours. 180. 1. Red and Gveen 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, _ Ternary Combinations of Complementary Colours with Grey. 221. Red., Green, dec. —1. Bed, Green, &c. 2. Grey, Bed, Green, Grey, &c. 3. Grey, Bed, Grey, Green, GO HARMONY AND CONTRAST OF COLOURS. Grey, Arc. If it be doubtful whether the binary assortment of grey, red, and green, be favourable, it cannot be called injurious. The third assortment is, perhaps, inferior to that in which the grey is replaced by black. 222. Blue and Orange. —1. Blue, Orange, ro- portv/n of sombre colours. 6G HARMONY AND CONTRAST OF COLOURS. Examples. Grey associates better than Black with— 1. Orange and Violet. 2. Green and Blue. 3. Green and Violet. 247. 11th. If, when two colours accord badly, there is in principle an advantage in separating them by White, Black, or Grey, it is important to the effect to take into consideration-—1. The height of tone of the colours. 2. The proportion of sombre to luminous colours, including, in the first, the broken brown tone of the brilliant scales, and in the luminous colours, the light tones of the Blue and Violet scales. Consider the height of tone of the colours. 248. The effect of white with red and orange is inferior as their tones become higher, especially in the assortment white, red, orange, white, 4:c.; the effects of the white being too crude. On the contrary, black unites very well with the normal tones of the same colours, that is to say, the highest tones without any mixture of black. Although grey does not associate so well as black with red and orange, it has the advantage of producing a less crude effect than white. Consider the proportion of sombre to luminous colours. 249. Whenever colours differ very much, either in tone or in brilliancy, from the black or white with which we wish to associate them, that arrangement where each of the two colours is separated from the other by black or white, is preferable to that in which the black or the white separate each pair of colours. Thus the assort¬ ment white, blue, white, violet, white, V 5? yy More vivid. Scarlet. Yellow r -orange. Yellow-green. Rusty-green. Orange-grey. Grey, slightly Orange-grey. Orange-maroon. Red-maroon. EFFECTS OF COLOURED LIGHT. 71 263. Modifications produced by Yellow light. Yellow rays falling on—- Black make it appear Yellow-olive. White Yellow Bed Orange Green Light Blue Deep Blue Indigo Yiolet Light Yellow. Orange-yellow. Orange. Yellower. Greenish-yellow Yellow-green. Green-slate. Orange-yellow, Yellow-maroon. 264. Modifications produced by Green light. Green rays falling on— Black make it appear Greenish-brown. White Green Bed Orange Green Indigo Yiolet Green. More intense and brilliant. Brown. Faint Yellow, a little Green. Greener, according to its depth. Dull Green. Bluish-green Brown. 265. Modifications produced by Blue light. Blue rays falling on Black make it appear Blue-black. Black White 99 Blue. Blue 99 More vivid. Bed 99 Violet. Orange c Brown, having a 99 99 99 ( pale tint of Violet. Blue 99 Yellow 99 Green. jj Green 99 Blue-green. jj 99 Indigo 99 Dark-bluelndigo. 99 99 Violet 99 Dark-blue Violet. 72 HARMONY AND CONTRAST OF COLOURS. 266. Modifications produced by Violet light. VioletraysfallingonBlaekmakeitappear j „ Violet. „ DeeperViolet. f Red-violet ” 1 Purple. „ Light Red. I Brown, with a n j very slight tint \ of Red. „ Light Purple. ( Pine Blue ” \ Violet. f Deep Blue ” \ Violet. 267. It is understood that to represent the preceding phenomena exactly, we must take into account the facility with which coloured light penetrates every kind of glass, the more or less intense colour of the stuff, and the kind of scale to which the coloured stuff and that of the transmitted coloured light respectively belong. 268. These observations were made by partially ex¬ posing coloured, stuffs to the sun’s rays transmitted through coloured glasses. The portion of stuff not exposed to these rays, was lighted by the direct light of the sun. The portion of stuff which received the action of the coloured rays being exposed to diffused daylight, reflected also rays of that light which it would have reflected in case it had been protected from the influence of the rays transmitted to it through coloured glasses. 269. II. Modifications produced by two lights of different intensity. White Violet Red Orange Yellow Green Blue Indigo EFFECTS OF LIGHT OF VARIOUS INTENSITY. 73 270. 1. The modification by the light of the sun falling upon one part of the surface of a coloured body, while the other part is enlightened by diffused daylight. 2. The modification produced when two parts of the same object are unequally illuminated by diffused day¬ light. An object lighted partly by the sun, and partly by dif¬ fused daylight. 271. To observe this kind of modification properly, let us expose to the sun a square piece of stuff A B, two and a-half inches broad (Plate III., fig. 1) and place in the middle a piece of black wire f f ; then put parallel to this, and in the middle between A and B, two wires e, e' and g, g f , of about three-tenths of an inch in width. The extremity g' is fixed upon a perpendicular plane h, h', of one and two-tenths of an inch in height, so that/,/', being in the plane of the direction of the solar rays, the plane h, h' covers exactly all the part B of the stuff, with its shadow. 272. i. If the stuff is red, the lighted portion A is more orange or less blue than the part B, which is in shade; and the portion a is more orange than the portion a', as the portion b is bluer than the portion b'. 273. 2 . If the stuff is orange, A is more orange or less grey than B ; and the portion a is deeper, more vivid than a', as b is more grey and duller than b'. 274. 3 . If the stuff is yellovj, A is more vivid, more orange than B; a is more so than a!, as b is duller than V. 27 5. 4 . If the stuff is green, A is less blue or more yellow than B ; and a is of a yellower green than a', as b is bluer than b'. 276. 5 . If the stuff is blue, A is less violet and more 74 HARMONY AND CONTRAST OF COLOURS. green than B ; and a is greener than a', as b is more violet or less green than V. 277. 6. If the stuff is indigo, A is redder or less blue than B : and a is redder than a', as b is deeper or bluer than b'. 278. 7 . If the stuff is violet, A is less blue than B; and a is redder than a' as b is bluer than b'. 279. 2nd. Two contiguous parts of the same object unequally illuminated by the same light, when viewed simultaneously, differ from each other, not only in depth of tone, but also in optical composition of colour. Place half-a-sheet of coloured paper (Plate III., fig. 2) upon the partition b, of a chamber receiving diffused daylight by a window /: place another half-sheet upon the partition a, in such a manner that it will be lighted directly by the diffused light, while the other is only indirectly lighted by reflection from the walls, floor, and ceiling : the diffused light thus reflected being only white light, then stand at c, so as to see both half-sheets at once. I shall designate that which is upon the partition a, and most lighted, by A, and the other, which is upon the partition b, and less lighted, by B. These letters in the plate indicate the respective posi¬ tions of the half-sheets. 280. The inference from these observations is, that the colour of the same body varies, not only in intensity of tone, but also of hue, according as it is lighted directly by the sun, by diffused daylight, or by diffused reflected light. This result must never be overlooked whenever we define the colours of material objects. 3rd. Modifications produced by diffused daylight re¬ flected by a surface all the parts of which are not in the same position relatively to the eye of the spectator. EFFECTS OF YAKIED POSITION. 75 281. Distant bodies are rendered perceptible to the eve only in proportion as they radiate or reflect, 01 transmit the light which acts upon the retina. According to the laws of reflection, it happens that those portions of a surface which are in relief, or hollow, must reflect the light in such a manner, that the eye ot the spectator, in a given position, will see these parts very variously lighted, in respect to the intensity of reflected light, so that the parts of this surface will be, relatively to the eye, in the same condition as the homo¬ geneous parts of a plane surface, which are illuminated by lights of unequal intensity. There will be this difference, however, that the parts of the surface of a body which appears to us hollow, and especially in relief, being but feebly varied in the greater number of contiguous parts, there will be generally a gradual diminution of the effects observed in the case in which we have studied the modifications of two plane homogeneous surfaces, lighted by diffused lights of unequal intensity. The sphere presents a remarkable example of the manner in which light is distributed over a convex surface, relatively to the eye of an observer, who views it from a given position. 282. I shall not occupy myself with this gradation of white light, from parts illuminated to those which do not appear so. I regard only the principal modifications, and take for examples the cases where they are as evident as possible. These modifications can be reduced to the four following :— First modification , produced by the maximum of white light which the surface of a coloured body is capable of reflecting. 76 HARMONY AND CONTRAST OF COLOURS. 283. Other things being equal, the more highly the surface of a body is polished, the more it will reflect white and coloured light. If we observe the surface of a stick of sealing-wax, suitably placed, we shall per¬ ceive a white stripe parallel to the axis of the cylinder, produced by so large a quantity of colourless reflected light that the red light reflected from this stripe is not appreciable by the eye. Thus the white light reflected by a coloured body may be of sufficient intensity to render the colour of the body in some of its parts im¬ perceptible. Second modification , produced by those parts of a coloured surface which send to the eye, in proportion to the coloured light, less white light than the other parts differently lighted, or differently placed in relation to the spectator. 284. When the eye sees certain parts of the surface of a polished or uniform coloured object which reflects to it proportionally to the coloured light less of white light than the other parts, the first parts will appear in most cases of a more intense tone of colour than the second. We will cite the following :— Example 1.—A cylinder of red sealing-wax presents, proceeding from the white stripe mentioned above, a red colour deeper in proportion as less white light reaches the eye. Thus, in a certain position where the white stripe appears to be in the middle of the cylinder, the part most lighted will appear coloured, reflecting a red inclining to scarlet, while that which is the least lighted reflects a red inclining to crimson. Example 2.—-If the eye is directed into a gold vase of sufficient depth, the gold does not appear yellow as on the exterior surface, but of a red orange ; because less effects of varied position. 77 white light, in proportion to coloured light, reaches the eye in the first case than in the second. It is for this reason that the concave parts of gold ornaments appear redder than the convex. Example 3.—The spiral thread of a piece of twisted silk or wool held perpendicularly before the eye, appears in the part opposite to the light, of a much more de¬ cided colour than on the rest of the surface. Example 4.—The folds of bright draperies present the same modification to an eye properly placed ; the effect is particularly remarkable in yellow silk stuffs, and in sky-blue ; for we can easily understand that it is less marked when the stuffs are not so bright and of dark colours. Example o .—There are some stuffs which appear to be of two tones of the same scale of colour, and some¬ times also of two tones of two contiguous scales, al¬ though the weft and the warp of these stuffs are of the same tone and the same colour. The cause of this appearance is very simple; the threads which, parallel to each other, form the designs, are in a different direc¬ tion to the threads which constitute the ground of the stuff. Hence, whatever may be the position of the spectator with regard to the stuff, the threads of the design will always reflect coloured and white light in a different proportion to that reflected by the threads of the ground, and, according to the position of a spec¬ tator, the design will appear to be lighter or darker than the ground. Third modification .—The colour complementary to that of a coloured object developed in one of its parts, in consequence of simultaneous contrast. 285. A natural consequence of the law of simulta- 78 HARMONY AND CONTRAST OF COLOURS. neous contrast in general, and of the effect of a colour upon grey and black in particular, is, that since the same object presents some parts more or less dark, con¬ tiguous to some parts where we see the colour peculiar to the object, the first parts will appear tinted with the complementary to this colour. But to observe this effect, it is necessary that the grey part should reflect to the eye white light, and little or none of the coloured light which the object naturally reflects. Fourth modification, in a single-coloured stuff. 286. For example, if the eye is directed from the back of a chamber towards a window which admits day-light, and a person clothed in a new blue coat, dyed with indigo or Prussian blue, looks through the window on the objects which are outside, the eye will see one part of the coat different from the other part, because the nap of the cloth is disposed in a contrary direction ; one appears of a fine blue while the other will be of an orange-grey, by the effect of con¬ trast of the blue part with a part that reflects very little white light to the eye, without, or almost without, blue light. 287. But as the pile of the nap loses its regular posi¬ tion by wear, the cloth becoming dull and soiled, the coloured light is reflected irregularly from all points; and if the effect is not absolutely destroyed, it is at least much weakened. If the garment be of a deep green, the grey part will appear reddish; if it be of a violet, maroon, or claret, the grey part will appear yellow. 288. The complementary is only developed upon cloths of dark and sombre colours; thus red, scarlet, orange, yellow, and light blue garments do not exhibit EFFECTS OF VARIED POSITION. 79 it, because they have always too much of the essential colour which is reflected. The modification occurs only when one of the parts is more strongly illuminated than the other by diffused light (279). 289. There is also one circumstance where the fourth modification will appear evident; it is when we look at a series of light tones—blues, rose, ossible at equal distances from each other. Such a plan, always easy to make, will enable a land- owner, when once his masses are planned, their con¬ centric lines traced, and the species to be [planted determined upon, to order from the nurseryman the exact number of each species he requires. 580. After tracing the lines of plantations, and putting in the stakes to mark out the centre of the holes to be dug, we must draw upon grey paper lines representing those of the masses we intend to plant, taking as many equidistant points as there are stakes in the corresponding lines of plan¬ tation ; we then fasten on these points wafers, or little circles of paper, of the colour of the flowers or the foliage of the plants, according to the desired effect-. By this means we can judge of the harmony of the colours of flowers with the different hues of green com¬ posing the mass, and thus rectify any defect in the plan before we begin to plant. The principles on which the preceding rules are founded are those of height, form, variety, facility of o 194 HARMONY AND CONTRAST OF COLOURS. development, and distinctness of view. Harmonious arrangement, with reference to these points, not being so exclusively the object of this work as the subject of colour, must be passed with this indication. Contrast of Colours. 581. This principle, regarded generally, is included in the preceding, since a difference in colour will render plants distinct which have numerous analogies; but viewed specially, it produces among perfectly dissimilar plants, effects which can only be obtained from colour; and it is then that the principle of contrast is to be taken into consideration. In the application of the law of contrast to the arrangement of flowers, we must never forget the diffe¬ rence between an assemblage forming a line of plants, and an assemblage of flowers belonging to plants of various heights, standing on different planes, so as to produce the effect of a picture. I have alluded to this before (551); for in a linear arrangement, for example, there is nothing more unpleasant than the blue flowers of the German iris, associated with the light violet of the lilac. But if we add to this association large tufts of alyssum saxatile, Persian iberis, and red tulips, so that the golden yellow, white, and deep red, appear on one plane, and the deep blue and the light violets on a more distant plane, we shall obtain general effects of a most agreeable kind. Repetition. 582. When a line of plants exhibits the repetition of the same species, and presents them regularly at the ARRANGEMENT OP PLANTATIONS. 195 same intervals, an effect is produced which, although very agreeable, is but little appreciated—for it is very rarely met with in gardens. It is especially the repeti¬ tion of a similar arrangement of colours that is agreeable, and which recommends the observance of this principle. Repetition of the same arrangement of plants of va¬ rious kinds, and of course distinct to view, contributes greatly to prolong the extent either of an alley or of a mass ; a si m i l ar general effect repeated a certain number of times becomes a standard, by means of which the eye judges the space to be greater than if it were bordered with individuals of the same species or variety equal in number to the former. This effect is carried to the utmost extent when the arrangement is composed of a certain number of tufts—five, for instance—placed between two trees, which rise above them, but not too high. Repetition and distinctness of view concur in pro¬ ducing an agreeable effect. 583. Variety, like every other principle, should never be carried too far, and it is a great mistake to suppose that plantations made without design, and which thus it might seem must be extremely diversified, produce in this respect more effect than those which have been arranged according to the principles of distinct view, contrast, and repetition. Whenever objects must have a certain superficial ex¬ tent, we gain nothing by multiplying varieties of them. Thus, the repetition of an arrangement of three colours, including white or black, will generally be more agree¬ able than that of an arrangement of five colours. Diversity of colours, pushed to the extreme, can only be permitted in a continuous border, or abed of different o 2 190 HARMONY AND CONTRAST OF COLOURS. varieties of the same species of flowers, as a border of larkspur, china aster, or anemones; but, for flowering shrubs, we shall gain everything by not indefinitely multiplying their colour, in a view which the eye can embrace at once. And as with colours so with forms, which must not be too diversified in the same arrange¬ ment. Symmetry. 581. We should deceive ourselves very much if we supposed the principle of symmetry to be excluded from landscape gardening. But, in order to perceive it or to put in practice, it is necessary to distinguish the sym¬ metry of similar parts, and the symmetry of parts merely corresponding. The former is that of two equal parts of one whole, as the two halves of a circle, of a square, of an equi¬ lateral or isosoceles triangle, &c.; while Symmetry of parts merely corresponding, is that of two parts of the same whole, which, without being equal, have the same form, or nearly so; such are the two tri¬ angular parts of the Mass 3, Plate IV. Or, that of two separate parts, more or less analogous in form, extent, or nature, which have a correspondence of position relatively to an intermediate object. Or, that of two masses or groups of trees, or of a mass and a group of trees which are presented, the one to the left, the other to the right. General Harmony. 585. In the general composition of a large landscape garden, it is not enough to have satisfied all these prin¬ ciples, if the different masses subordinated together, GENERAL PRINCIPLES. 197 which we shall now regard as individuals, as well as the various constructions of wood or of stone, are not com¬ bined by some harmonious relation suitable for satisfying the principles of general harmony. The isolated or subordinated masses near or distant from each other must be allied together by the same vegetable form or by analogous forms, or by the same arrangements of several species ; or, lastly, by the same colours of flowers or of foliage. By the aid of similar means, we ally the house and other buildings to the different parts of the garden. When the neighbouring masses, especially those formed near buildings, are not sufficiently allied toge¬ ther, or the perspective of their concentric or median lines is not satisfactory, we have recourse to a different line of vegetation, which cuts the first and thus adds to the general harmony. Thus, as I have so strongly in¬ sisted, when we decide to plant evergreens in a land¬ scape-garden, they must be distributed throughout the composition. Sixth Division. INTERVENTION OF THE PRECEDING PRINCIPLES IN THE JUDGMENT OF COLOURED OBJECTS, RELATIVELY TO THEIR COLOURS, CONSIDERED INDIVIDUALLY, AND TO THE MANNER IN WHICH THEY ARE ASSOCIATED. 586. In this division my object is purely critical. The positive conclusions at which I have arrived upon certain assortments of colours, so as to derive the best result from them under given circumstances, become rules, adapted to guide those who would judge a work of art in which such assortments occur. The generaliza¬ tions established in the preceding chapters, with the 198 HARMONY AND CONTRAST OF COLOURS. object of aiding tlie numerous artists who use colours, now critically considered, will serve as the basis of a conscientious and sound judgment upon the merit of any work in which these generalizations are concerned. They will, I trust, possess the double advantage of all the rules involved in the nature of such things; they guide the workman who does not disdain them, and they direct the critic who judges the work of which these rules govern some element. We cannot then refuse to recognise the utility of such an examination, both for artists and for the public, to whom they are more par¬ ticularly addressed, in the hope that a clear demonstra¬ tion of what is laudable or censurable will form such a public taste as, by preventing a reliance on first impres¬ sions, will lead to a sound judgment; and that we may not henceforth strive to enlist public suffrages by falling into unsuitable singularity, or by wandering from the truth. 587. If there exists a subject worthy of being studied critically on account of the frequency and variety of the cases it presents, it is unquestionably this; for whether we contemplate the works of nature or of art, their varied colours form one of the finest spectacles man is permitted to enjoy. Hence the desire of reproducing the coloured images of objects which excite our admira¬ tion or interest, has produced the art of painting. The imitation of the painter’s works has given birth to tapestry, and carpets, and mosaics; while the necessity for economically multiplying designs has led to orna¬ mental printing. The love of colour has also induced man to paint his dwelling and to dye his garments and household decorations. 588. The sight of colours, so simple a thing for the GENERAL PRINCIPLES. 199 greater part of mankind, is, according to some philoso¬ phers, a phenomenon entirely out of the domain of positive knowledge, inasmuch as they consider that it varies with the organization, and even the imagination, of individuals ; consequently, they think that it cannot be inferred that, because one man sees an object in a certain way, another will see it in like manner under the same external circumstances. They believe that no generalization, deduced from observation, can direct the artist with certainty, either in the art of seeing his model or in faithfully reproducing a coloured image of it: they also think that no useful physiological generalization can arise from a profound study of the modifications his organs experience from the sight of the colours that bodies present to him. I cannot admit that we ought to abstain from the study of a subject because it presents variable phe¬ nomena. All those who are engaged in the study of the positive sciences, should inquire for some fact capable of illus¬ trating the study of these phenomena. 589. I entered upon this study, not having spontane¬ ously chosen it, but because it appeared to me indis¬ pensable before pretending to establish a sound judgment on the beauty of the colours of the dyer. As soon as I felt the necessity for this study, in my capacity of Director of the Dyeing Department of the Royal Manu¬ factories, my first care was to discover if I saw colours as the generality of persons see them. I was soon per¬ fectly convinced that I did, and not till then did I venture to make my researches the objects of public lectures. These have been repeated before the students of the Polytechnic School. Certain questions addressed 200 HARMONY AND CONTRAST OF COLOURS. to my auditors to satisfy me that they saw the things I put before their eyes as I saw them myself, have, in the majority of cases, always proved them to be so, and yet my demonstrations were given in the reception-hall at the Gobelins,—a place ill adapted for the exhibition of the phenomena of contrast to a large audience. Certain observations by myself, tested by a great number of per¬ sons in my laboratory, and afterwards publicly exhibited, form the subject of this book; all who repeat my ex¬ periments will discover -whether my opinion is well- founded, or whether an opinion is correct which pretends that the sight of colours is not capable of giving a general positive result. Because some individuals have organs of sight so imperfect that they cannot distinguish green from red, or blue from grey, Arc., must we write our treatises on optics without mentioning either red, green, or blue, and cast away these colours from the palette of the painter? Truly human nature is but too limited to allow of our making such a sacrifice of our common organization to the infirmity of an individual. 590. In order to comprehend clearly how experiment and observation, after having disentangled the causes which exercise a determinate influence upon the sight of colours, led me to adopt the opinion that these phe¬ nomena are perfectly defined by the law of contrast and the conclusions therefrom, doubtless it will suffice to consider how i. Our former ignorance respecting the different states of the eye, which, in seeing colours, give rise to the phe¬ nomena of simultaneous, successive, and mixed con¬ trasts. And our former ignorance respecting the definite influence that the direct or diffused light of the sun exer- HISTORY OF THE AUTHOR’S INQUIRIES. 201 cises, according to its intensity, upon the colours of bodies, have led to the establishment of an opinion contrary to my own,—that is to say, the opinion that the same colour appears so diversely to different persons, and even to the same person, that nothing general or pre¬ cise can he deduced from the sight of coloured objects, 'with regard to their respective colours. 2 . To consider how the following have passively con¬ tributed to belief in this opinion. The limited number of ideas we have generally upon the modifications of coloured bodies, by their mutual mixtures; or in other terms, upon the colours resulting from these mixtures. The w T ant of a precise language to convey the impres¬ sions we receive from colours. Of recapitulating how the following causes have actively contributed to establish belief in this opinion. In exact ideas which are supposed to be estab¬ lished. 591. It is indisputable that if we are ignorant of the regularity with which the eye passes successively through stages, the extremes and the mean of which are very different, in viewing the colours which put the organ into the condition of perceiving the phenomenon of one of the three contrasts (77) we shall be led to consider the sight of colours as a very variable phenomenon, while the successive stages through which the organ passes being once distinguished, the variations of the phenomenon become perfectly definite. 592. If we are ignorant of the law of simultaneous contrast, we shall suppose that the same colour varies in tint according to the colour with which it may be asso¬ ciated ; and if we are ignorant that contrast affects the 202 HARMONY AND CONTRAST OF COLOURS. tone as well as tlie colour, we cannot explain how two similar colours (for instance, blue and yellow at the same depth of tone) will appear redder by juxtaposition ; while, if the blue is very deep relatively to the yellow, it will appear black, rather than violet, and the yellow will appear more green than orange. Finally, if we are ignorant of the effect of the brightness which a com¬ plementary can give to a dull colour, we cannot explain the great difference there is between the effect that a red ground has upon imitative gilt ornaments, and the effect of the same ground upon metallic gilt ornaments (384). 593. Doubtless, also, if it be not known that in a complex object, the eye can only see clearly at the same moment a small number of parts and that the same part may appear to different eyes with different modi¬ fications, according as it is seen juxtaposed with one or another colour, as in the instance given (407). 594. We might know the regularity of the successive states of the eye during the sight of coloured objects, and the law of simultaneous contrast of colours, and yet, if we were ignorant of the influence of various degrees of intensity of light in varying the colour of bodies and in rendering the modifications of contrast more or less evident, we should be led to believe in an indefinite variation in the aspect of colours; but this variation is perfectly defined by the following remarks:— If the direct light of the sun or diffused daylight illuminates a monochromous body unequally, the part most vividly lighted is modified as it would be if it received orange, and the modification appears the stronger the greater the difference of light on the parts (280) : thus the more intense the light, the more it gilds the body it illumines ; it is thus always easy to VALUE OF THE KNOWLEDGE OF CONTRAST. 203 foresee the effects of it when we know the result of the mixture of orange with various colours. 595. The phenomena of simultaneous contrast being less evident in a very vivid light than in a weaker light (63), it follows that if we disregarded the difference in the effects, we should greatly deceive ourselves in our appreciation of the phenomena of contrast of similar colours. Simultaneous contrast, which tends to make the differently coloured parts appear as distinct as pos¬ sible, is carried to a maximum, precisely when the light being feeble, the eye requires the greatest contrast of colour to perceive distinctly the various parts upon which it is fixed. 596. We may perceive the modifications presented by bodies when lighted, and yet we may experience much difficulty in accounting for them, for want of knowing how to represent exactly the modifications which the coloured materials experience, in their colour, according as they receive light or white, shade or black; or according as they are mixed together. It is partly to make these modifications clearly known that I have designed the chromatic hemisphere (134, et seq.'). In describing it, I have attached less importance to its material realization than to the rational principle upon which it depends. On looking at the lines of this dia¬ gram independently of all colouring, we understand how any colour is reduced by white, deepened by black, and broken by black and white, and how, by mixture with a pure colour, it produces hues. I shall add sub¬ sequently some new considerations on the gradations of colour made with coloured materials. My object would not have been attained had not the chromatic hemisphere given me the means of 204 HARMONY AND CONTRAST OF COLOURS. representing, by a simple nomenclature, the modi¬ fications which a colour undergoes by the addition of white and black, modifications which produce the tones of its scale; those which it receives from black yielding broken scales, and those resulting from the addition of a pure colour, produce scales which are hues of the first colour. 597. Finally, to the definitions which I have given of the words tone, scale, hue, broken colours, I must add the distinction of the associations of colours into har¬ monies of analogy, and harmonies of contrast (172). I am convinced that all those who accept the small number of definitions I have given, will find much ad¬ vantage from them in accounting for the effects of colours, and in expressing their views to others. By their aid it will be easy to notice relations which might have escaped observation, or which, in the ab¬ sence of precise language, could not have been clearly communicated. 598. It would be ignoring a fact to attribute the opinion I have combated, exclusively to ignorance of what I have just recapitulated, or to believe, that in order to establish the contrary opinion, which I main¬ tain, it is sufficient to dissipate this ignorance. But I am satisfied with pointing out the error, with¬ out making the least pretension to overthrow it, other¬ wise than by stating what I believe to be the truth. 599. The study of the positive facts just reviewed, leads to a certainty in the view of colours which all may acquire who devote themselves to it. They will see how fruitful it is in applications, and that it is inde¬ pendent of every hypothesis, and that it would be im¬ possible to obtain this result, if there did not commonly JUDGMENT OF CONTIGUOUS COLOURS. 205 exist among men an average organization of tlie eye, which permits them to perceive in similar circumstances the same modifications, but with varied intensity of per¬ ception. 600. Having noticed the series of principles upon which my book is founded. I next consider these facts under the three following relations :— 1. The certainty they give in judging of the colour of an object. 2 . The certainty they give to our judgment in the various arts which address the eye by coloured ma¬ terials. 3 . The union they establish between the principles common to many arts, which speak to the eye as it were various languages, in employing different materials. 4 . The influence that the disposition of the spectator’s mind may have upon his judgment of a work of art. Section I. ON THE CONNEXION OF THE LAW OF SIMULTANEOUS CONTRAST OF COLOURS WITH THE JUDGMENT WE FORM UPON ALL COLOURED BODIES, UNDER THE RELATIONS OF THE RESPECTIVE BEAUTY OR PURITY OF THEIR COLOURS, AND OF THE EQUALITY OF THE DISTANCE OF THEIR TONES IF THESE BODIES BELONG TO THE SAME SCALE. 601. The most simple and general conclusion deduced from the law of contrast is certainly that which concerns the judgment we exercise, either by taste or profession, on a colour, whether presented by a coloured paper, a textile fabric, a glass, an enamel, a picture, &c. All those who have some experience in the matter consider 206 HARMONY AND CONTRAST OF COLOURS. one condition as essential to be fulfilled to avoid error, namely, that the colour concerning which we have to determine be compared with another colour analogous to it. If we are ignorant of the law of contrast, the result of this comparison is not exact, whenever the objects compared are not identical. I now proceed to demonstrate this by examples adapted to the application of the principle spoken of. Further, a more remote consequence of the law affords the means of knowing whether the tones of a scale of wool or silk are equidistant. ON THE COMPARISON OF TWO SAMPLES OF THE SAME COLOUR. 602. When we have to do with two patterns of any kind, which are related to the same colour, if there is no identity between the tints, we must take into account the contrast which exaggerates the difference : thus if the one be greenish-blue, it will make the other appear less green, or more indigo, or even more violet, than it really is ; and, reciprocally, the first will appear greener than when viewed alone ; the same with the reds, if one is more orange than the other, the latter will appear more purple, and the former more orange, tl an they really are. INFLUENCE OF A SURROUNDING COLOUR T PON ONE COLOUR WHEN COMPARED WITH ANOTHER. 603. Since the contrast of colours which are not analogous, tends to improve and purify them, it is evi¬ dent that whenever we would exercise a correct judg¬ ment upon the beauty of colours, after comparing them with the colours of objects analogous to the first, we must take into account the kind of work, and the manner INFLUENCE OF ONE COLOUR ON ANOTHER. 207 in which they are juxtaposed, if the objects compared are not the exact representation of the same subject. For, other things being equal, the same colours not blended, and which are not sufficiently analogous to in¬ jure each other, will certainly appear more beautiful disposed in contiguous bands than if each were seen on a ground which consisted of it exclusively, and which consequently produced only a single impression of colour upon the eye. Colours forming palms like those of Oriental shawls or patterns, as of Turkey car¬ pets, produce a much greater effect than if they were shaded or blended, as they generally are in paintings. Consequently, for example, in comparing a stripe of crimson in a Cashmere shawl of various stripes with the crimson of a French shawl, we must destroy the contrast of colours by placing around it a piece of grey or white paper, cut out so as to allow this stripe only to be seen, when the parts compared will be submitted to the same influence from the surrounding objects. 604. So, when we compare the colours of old tapestries, pictures, &c., with colours recently dyed or painted. Time acts very unequally, not only on the different kinds of colours of dyed stuffs, but also upon the tones of the same scale. Thus, the deep tones of certain scales,—those of violet, for example,—fade, while the deep blues of the indigo-blue scale, the deep tones of madder, kermes, cochineal, are permanent. Also, the light tones of the same scale fade during a time which has no sensible effect in altering its deep tones. Whence the colours which have most resisted the destructive action of time, being more isolated from each other, as well as deeper and less blended, appear to have more brilliancy. 208 HARMONY AND CONTRAST OF COLOURS. There are many pigments, as most of the lakes, which are in the same condition as compared with ultramarine, the oxides of iron, the blacks, Arc. On the Effect of Contrast upon the Browns and the Lights of most of the Scales of Wool and Silk employed in Tapestry and Carpets. 605. When we look at the whole effect of tones of most of the scales made use of in these manufactures, the phenomenon of contrast exaggerates the difference of colour observed between the extreme and the middle tones of the same scale. For instance, in the scale of indigo-blue, applied to silk, the lights are greenish, the browns are tinged violet, while the intermediate tones are blue ; but the difference of green and violet at the two extremes is augmented by the effect of contrast. So in the scale of yellow, the light tones appear greener, and the browns redder, than they really are. 606. In speaking of a difference existing between the deep and the light tones of most of the scales of wool and silk, which is exaggerated by contrast, I will add some remarks relative to the gradations the dyer produces. This gradation is very seldom perfect, as the light tones are exactly represented to the eye by the colour taken at its normal tone, reduced by white. Thus, a compound which at the normal tone is pure yellow, or slightly tinged with orange, will, by reduction, produce light tones of a greenish-yellow. An orange-red compound upon silk or wool will yield light tones tinged violet-red. To obtain a correct gradation, we must in most cases add to the weak tones a new coloured material, adapted to neu¬ tralize or weaken the defect spoken of. OF JUDGING WHETHER TONES ARE EQUIDISTANT. 209 GOT. Many of the colouring matters used in painting produce the same result when reduced with white. I do not speak here of changes which may be the effect of chemical action ; I allude only to those which result from an attenuation of the coloured material. For example, the normal tone of carmine is a much purer red than its light tones, which are evidently tinged with lilac. Ultramarine, so beautiful in itself, yields light tones which, with respect to the blue rays, appear to re¬ flect more violet rays than the normal tone. In conse¬ quence of these facts, it is difficult to colour the chro¬ matic diagram, because many trials must be made to obtain the modification of colour which yields the normal tone of a scale, by the addition of such coloured materials as will render the gradation correct. MEANS AFFORDED BY CONTRAST FOR ASCERTAINING WHETHER THE TONES OF A SCALE OF COLOUR ARE EQUIDISTANT. 608. Contrast, which augments the difference ex¬ isting between two tones of the same colour, affords the means of judging with greater certainty than could otherwise be done, whether the numerous tones of a scale are at the same distance from each other. Thus, if the tone 2, placed between 3 and 4, appears equal to the tone 1, it follows, if the tones are equidistant, that 3 placed between 4 and 5 will appear equal to 2; that 4 put between 5 and 6 will appear equal to 3, and so with the others. If the tones are too near together to yield this result, we must move them successively, not one degree, but two or three. This means of judging of the equality of distance that separates the tones of the same scale, is based upon the fact, that it is easier to v 210 HARMONY AND CONTRAST OF COLOURS. establish an equality than to estimate a difference between patterns of the same colour. OF THE BINARY ASSOCIATIONS OF COLOURS, CRITICALLY CONSIDERED. 609. In order to sum up in few words the gene¬ ralities which must serve as the bases of our judgment, not 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, we must consider combinations both of complementary and non-comple- mentary colours. 1st. Combination of Complementary Colours. This is the only association ivhere the colours mutually improve, strengthen, and purify each other without leaving their respective scales. This case is so advantageous to the associated colours, that the combination is also satisfactory when the colours are not absolutely complementary, also when they are made dull with grey. I therefore prescribe the com¬ plementary association when we have recourse to the harmonies of contrast in painting, in tapestry, in the arrangement of coloured-glass windows, in the assort¬ ment of hangings with their borders, in that of stuffs for furniture and clothing; and, lastly, in the arrange¬ ment of flowers in our gardens. 2nd. Combination of N'on-complementary Colours. The product of this combination is distinguished from the preceding in this,-—the complementary of the juxta¬ posed colours, differing from the other colour to which it is added, there must necessarily be a modification of hue in BINARY COMBINATIONS CRITICISED. 211 the two colours, as well as a modification of tone, if they are not taken at the same height. 610. Juxtaposed non-complementary colours can cer¬ tainly give rise to three different results :— 1. They may improve each other. 2 . The one may be improved, the other may lose some of its beauty. 3 . They may injure each other. The greater the distance between the colours, the more favourable will the juxtaposition be to their mu¬ tual contrast ; consequently, the more analogy they will have, and the more chances there are that the juxta¬ position may injure their beauty. 1. Two non-complementary colours improve each other by juxtaposition. 611. Yellow and blue are so dissimilar, that their contrast is always sufficiently great for their juxta¬ position 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, may be improved, while the latter may be injured. 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, neutralizing its excess of blue, rather improves than injures it. 3. Two non-complementary colours may injure each other. A violet and a blue are reciprocally injurious, when the first greens the second, and the latter neutralizes suffi¬ cient of the blue in the violet to make it appear faded. p 2 212 HARMONY AND CONTRAST OF COLOURS. It might also happen that although the colours juxta¬ posed be modified, neither gaining nor losing in beauty, that the one may gain without the other losing; lastly, that the one may neither gain nor lose, while the other loses. 612. In the association of two colours of equal tone, the depth of the tone may have some influence on the beauty of the association. For example, a deep indigo-blue and an equally deep red, gain by 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 the same scales, it may happen that the blue will become too green to be good as a blue, and that the red, ac¬ quiring orange, will be too yellow to be a pure red. 613. 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 purity the colour from whatever grey it may have. 614. It is very necessary for the correction of our judgment of these principles on the binary associations of colours, not to lose sight of all that precedes, con¬ cerning colours that are “ dead” (mat), or without gloss, and that their combination be considered independently of the form of the objects presenting them, for the two¬ fold reason, that the glossiness of the coloured surfaces, and the form of the bodies which these surfaces bound, may modify the effect of two associated colours; con¬ sequently, the analysis I have made of the optical INFLUENCE OF GLOSS AND FORM. 213 effects of colours would be incomplete without speaking of the possible influence of these causes. Influence of Gloss taken into consideration in the Effect of Contrast of two Colours. 615. The optical product of the juxtaposition of con¬ trasted flat colours is composed of two effects :—1. The effect which arises from each of the juxtaposed colours, by receiving the complementary of the colour contiguous to it, is thus strengthened or tinged agreeably, indepen¬ dently of any augmentation of gloss. 2. The effect arising from gloss in the two juxtaposed colours. Here it may be remarked that associations which I have not prescribed, such as red with violet, or blue with violet, have a fine effect in the plumage of certain birds and butterflies; for, in these natural associations, the effect arising from the addition of the complementaries to each, which would injure the flat colours, is entirely insensi¬ ble in surfaces which acquire metallic brilliancy from their organic structure. Finally, I shall add, that it would be necessary, before raising the objection, to demonstrate that the same red, associated with green, the same violet associated with yellow, and the same blue associated with orange, equally glossy, would be less effective than in natural assortments. Influence of Form taken into consideration in the Effect of Contrast of two Colours. 616. Elegance of form, the arrangement of the parts, their symmetry, the effects of light and shade, and the association of ideas which may connect this form with an agreeable recollection, will prevent the perception of the ill effect of two associated colours, even when not 214 HARMONY AND CONTRAST OF COLOURS. glossy. Thus, for example, in flowers, combinations, which would not produce a good effect upon two plain surfaces, are very beautiful. For example, the flower of the sweet pea, which has the combination of red and violet. 617. The critic must be directed by the considerations here summed up :— 1. The kind of association : the greater the difference between the colours, the more they beautify each other; and, inversely, the less difference there is, the more they will tend to injure one another. 2 . The equality in depth of tone. 3 . The difference of tone, the one being deep, the other light. 4 . The glossiness of the surfaces which reflect the colours to the eye. 5 . The form of the coloured body. OF THE COMPLEX ASSOCIATIONS OF COLOURS, REVIEWED CRITICALLY. 618. It is evident that the rules prescribed forjudg¬ ing of a colour, and the associations of two colours, in an absolute manner, must serve for judging under the colours of an association, however complex it may be. We shall consider the masses of colours which are upon the same plane, the extent which each occupies, and the harmony which unites them together. On submitting to a similar examination the colours on the other planes, we can then look at the colours of the latter. The critic who is well satisfied with seeing clearly at the same time, only a very small number of the objects COMPLEX ASSOCIATIONS CRITICISED. 215 that a picture presents to him and who is also accus¬ tomed to examine a coloured composition in this man¬ ner, is in the position of a person who reads in suc¬ cession writing on the same side of a sheet of paper; one series of lines crossing the first at right angles, and the third composed of lines running diagonally across the paper. The critic must review the ensemble of the picture as to its colours, and then, being attentive to their particular and general associations, he will be in a condition to enter into the thought of the painter, and to see whether he has employed the most suitable har¬ monies to express it; but this subject belongs to the following chapter, although it is easier to form with opposed colours than with neighbouring colours binary assortments favourable to the associated colours, yet, when a great number of pure and brilliant colours are employed, it is more difficult to harmonize them than if we produced the effect with a small number of colours, which would involve only the harmony of analogy, or that of scale, or of hue. 619. Although harmony of contrast most favourably causes two colours to impart value to each other, yet, when we desire to derive the greatest advantage from a union of numerous brilliant colours in any work—a a picture, for instance,—this diversity presents some difficulties in the general harmony, which a smaller number of colours, and especially of brilliant colours, would not present. It is, therefore, evident that, if we compare two effective pictures, well adapted to be judged under the relation of colour (other things being equal), the one which presents more harmony of contrast of colour will have the greater merit, on account of the difficulty overcome in the employment of the colours ; 216 HARMONY AND CONTRAST OF COLOURS. but it must not be inferred that the painter of the other picture is not a colourist; for the art of colouring is composed of several elements, and the talent of opposing pure colours to each other, is only one of these ele¬ ments. 620. Let us now consider the relations existing be¬ tween the subjects of painting and the harmonies they admit of. We know that the more pictures address the eye by numerous contrasts, the more difficulty the spec¬ tator experiences in fixing his attention ; especially if the colours are pure, varied, and skilfully distributed upon canvas. It results, therefore, from this, that these colours, being much more vivid than the flesh tints, the painter who wishes that his idea should be found in the expression of his figures, and who, deeming this part of his art superior to the rest, is convinced that the eyes of most people ignorant of the art of seeing, being carried away by their first impressions, are incapable of return¬ ing from these to receive others ;—the painter, I say, who knows all this, and is conscious of his power, will be restrained in the use of harmonies of contrast, and pro¬ digal of the harmonies of analogy. But he will not derive advantage from these harmonies, especially in a subject covering a vast space filled with human figures, as the “ Last Judgment” of M. Angelo, unless he avoids confusion by correct drawing, by a distribution of the figures in groups, skilfully distributed over the canvas, so that they may cover it almost equally, yet without cold symmetry. The eye of the spectator must embrace all these groups easily, and seize the respective posi¬ tions ; while in looking into one of them he must dis¬ cover a variety which will invite his attention to other groups. PAINTING IN FLAT TINTS. 217 621. The painter who fails to gain the effects of the physiognomies, &c., in having recourse to the harmonies of analogy, will not have the same advantage in fixing general attention, as the painter who employs the har¬ monies of contrast. The harmonies of contrast of colour are especially applicable to scenes (illumined by a too-vivid light), representing fetes, ceremonies, &c., which may be sober without being mournful; they are also applicable to large subjects, comprising groups of men animated with various passions. The result of this view is, that the critic must never compare the colouring of two large compositions without taking into account the difference which may exist in the suitableness of each subject with one kind of harmony more than with the other. Painting in the Flat Tints. 622. To apply painting in flat tints to historical, por¬ trait, and landscape painting—in a word, to the imita¬ tion of any object of which we can produce a faithful representation, would be going back to the infancy of art ; but to abandon it to practise exclusively the system of painting where all the modifications of light are repro¬ duced according to the rules of chiaro-’scuro, would be an error which can be demonstrated beyond question. 1. That, in every instance in which a picture must be placed at such a distance from the spectator that the de¬ tails of chiaro-’scuro will not be visible, we must have recourse to flat tints,—not neglecting, however, to use masses of light and shade adapted to give relief, if it is considered suitable. 2 . That, in every case where the picture is necessary 218 HA.RMONY AND CONTRAST OF COLOURS. to the decoration of an object, flat tints are preferable to chiaro-’scuro, because the use of the object almost always prevents the picture which ornaments it from being clearly seen under all circumstances. Thus painting in flat tints is preferable to the other— For ornamenting boxes, tables, screens, which, from the various positions their use requires, only allow to be seen a part of the pictures which decorate them; or, if the paintings are entirely visible, as those of a screen, they will be presented relatively to the daylight in a manner quite different from each other, on account of these various positions of their parts ; For decorating curved surfaces, as those of vases, the surfaces of which are never plain. 3 . That the qualities peculiar to painting in flat tints are Purity of outline ; Regularity and elegance of forms; Beautiful colours properly assorted. Whenever suitable, the most vivid and the most con¬ trasting colours may be advantageously employed. Simplicity in the whole, so as to render clear and distinct view easy. OF THE ARTS WHICH ADDRESS THE EYE BY EMPLOYING COLOURED MATERIALS OF A CERTAIN SIZE, CONSIDERED RELATIVELY TO THE PHYSICAL CONDITION OF THESE MATERIALS, AND TO THE PECULIARITY OF THE ART EMPLOYING THEM. 623. If we examine paintings with sufficiently power¬ ful magnifiers, we shall see that the coloured material, far from being continuous in all its parts, is in separate PRINCIPLES INVOLVED IN TAPESTRIES, ETC. 219 particles, and consequently, if the naked eye does not perceive them separately, it is because they are too small. In fact, the coloured threads (elements of tapestries and carpets), and rigid coloured prisms (elements of mosaics), which are visible to the naked eye, may be reduced to such a state of division, and so mixed and combined, that at the distance from which we view them united they appear as a uniform coloured surface.as if painted ; whence the possibility of making, with these elements, works which correspond to those painted in chiaro-’scuro; but it will be easier to execute such as correspond with flat tints. TAPESTRIES, CARPETS, MOSAICS, AND COLOURED GLASS WINDOWS, CORRESPONDING TO PAINTINGS IN CHIARO- ’3CURO. Tapestries with Human Figures. 624. Tapestries with human figures derive their origin from the taste of mankind for painting. They had adorned churches, palaces, and castles, before they appeared in simple dwellings. From the filamentous condition of the elements con¬ stituting them, their size, the direction the weaver gives them in twisting the weft upon each thread of the warp, results a coloured image presenting two systems of lines cutting each other at right angles. From this structure it results,—that a tapestry will not produce the effect of a painting (the surface of which is entirely uniform), if the spectator does not view it from a point sufficiently distant; so that, these lines ceasing to be visible, the de¬ lineation which separates each part of the design from the contiguous parts, will appear like the delineations of 220 HARMONY AND CONTRAST OF COLOURS. a painting, as much so as the indentations of the outlines which are oblique to the weft will permit. Hence the objects represented by it must be large, of various colours, forming harmonies of contrast rather than harmonies of analogy. 62 5. Every model which does not fulfil the previous conditions is bad, and as, in pictures which have not been painted with the intention of being reproduced hr tapestry, it is difficult to meet with the union of pure outline with harmonies of colours sufficiently numerous and contrasted, it follows that what would be very ad¬ vantageous to the art, is the execution of pictures in¬ tended to serve exclusively as models, painted broadly, so as to resemble, in some degree, painting in flat tints. The weaver not having, at least at present, models painted on this system, has to make, not only, as we say, a translation, but also a free and not a literal translation, of the model; and it is this, in my opinion, which dis¬ tinguishes the artist-weaver from the mere workman. Far from contending, then, with painting, the weaver, on the contrary, must study the circumstances in which he should yield in the struggle, so that he may avoid the difficulties with the means at his disposal; and when, especially, he must deviate from his model. Tapestries for Furniture. 626. The preceding consideration respecting the size of objects that figured tapestries should reproducers not applicable to tapestry for furniture, seeing that the threads of the warp produce lines which, far from being- disagreeable, are often imitated by the paperstainer. 627. These fabrics being intended for chairs, couches. CRITICAL REMARKS ON TAPESTRY. 221 curtains, screens, ainters, 94. Green, complementary to red, 15, 17, IS, 20 ; to violet, 44. Green and black, effects of juxtaposition of, 20. Green and blue, change by juxtaposition, 27; assortments of with white, 53 ; with black, 58 ; with grey, 62. Green and grey, effects of juxtaposition of, 22. Green and violet, change by juxtaposition, 26 ; assortments of with white, 53 ; with black, 58. Green and white, effects of their juxtaposition, 18. Green and yellow, change by juxtaposition, 27. Green draperies, 170. Green light, modifications produced by, 71. Greenish yellow, complementary to violet, 3, 16, 17, 21. Greenish yellow and black, effects of juxtaposition of, 20. Greenish yellow and white, effects of their juxtaposition, IS. Grey, juxtaposition of coloured bodies with, 21; assortments of different colours with, 58,63 et seq .; its association with luminous and sombre colours, 65, 66. Grounds, black, of paper-hangings, 125 ; various-coloured ones, 126-135. Grove, definition of a, 187. H. Hair, black, colours of bonnets suited for, 176. Hair, fair, colours of bonnets suited for, 175. Hair and head-dresses of women, colours of the, 168. Hangings, coloured, for the interior of a house, 152-7; colour of the wainscoting, relation to the, 155. Harmonies of contrast, 48, 217; analogy of in gardening, 182, 183, 184. Harmony of colours, 46; distinct kinds of, 48; law of, 95 ; between masses of trees in gardening and plantations, 192. Harmony and contrast of colours, 1 et seq. (See Colours.) Head-dresses of women, colours of the, 171; effect of upon the complexion, 171-4. Hieroglyphics, Egyptian, colouring of, 139. Horticulture, applications of colour to, 179 ; how to derive the greatest advantage from the various colours of flowers, 180 ; assortments of flowers, so far as they relate to the harmonies of contrast of colours, 1S1; contrast of hues, 182; harmonies of analogy, 182, 183 ; assortments of INDEX. 233 plants, 1S4; distribution of trees, 185 ; lines of plants, 187,188; homo¬ geneous masses of plants, 189 ; varied and isolated masses, 190 ; har¬ mony between masses distant from each other, 192 ; arrangement of plantations, 1S3 ; symmetry and general harmony, 196 ; general prin¬ ciples of, 197 et seq. Houses,decorations for'the interior of, 152; hangings, 152-7; cornices, 157 ; chairs, sofas, &c., ib.; on decorating the different rooms of the, 159; and their appropriate assortments, 160 ; carpets, 161; pictures, 162. Hues, definition of, 34, 35; harmony of, 48; harmony of contrast, ib.; harmonies of contrast in flowers, 182 ; analogy of, 183. Human figures, tapestries for, 219. I. Imitation of colouring, 101. Indigo, complementary to orange-yellow, 3, 16, 17. Indigo and black, effects of juxtaposition of, 21. Indigo and grey, effects of juxtaposition of, 22. Indigo and red, changed by juxtaposition, 27. Indigo and violet, changed by juxtaposition, 27. Indigo and white, effects of their juxtaposition, 19. Interiors of buildings, painters of, 101; various assortments of colours in, 143; stuffs with the wood of seats, ib. ; frames for pictures and engrav¬ ings, ib.; of churches, 147; of museums and galleries, 149 ; of houses, 152 et seq.; when the walls are panelled, or covered with marble or stucco, 163. J. Juxtaposition of colours, 11,211,212; of coloured surfaces with white, 18; with black, 19; with grey, 21; of coloured bodies belonging to the same group of coloured rays, 24. L. Landscape, colours used in, 95 ; in paper-hangings, 121-3. Landscape gardening, 179. (See Horticulture.) Light, different rays of, 1; its combinations of colour, 55. Light, modifications of, 69 et seq. Light, influence of on printed or written paper, 137 ; contrast of tone in, 138. Lights of wool and silk employed in tapestry and carpets, effects of con¬ trast on the, 208. Lines of plants, their arrangement, 187, 188. Luminous colours, 50 ; their association with black, 64 ; with grey, 6-5, 66. M. Marbles, in the interior of a building, assortment of colours for, 164. Men’s clothing, colours of, 165, 166. Mixed contrast of colours, 29-33, 88. Mixtures, of the three primary colours, 108. 234 INDEX. Modifications of coloured light, 69, 70 et seq.; of white light, 75 et seq. Mosaics, corresponding to paintings in chiaro-’scuro, 219, 222 ; in flat tints, 224. Museums, on the interior decoration of, 149, 151. N. Natural History, museums of, on the interior decoration of, 151. Noil-complementary colours, combination of, 210, 211. O. Opposition of colours, 67. Orange complementary to blue, 3, 16, 17, 18, 20 ; placed in juxtaposition with scarlet-red, 24 ; complementary to green, 43 -, to violet, 44 ; effects of its predominance in a picture, 100. Orange and black, effects of juxtaposition of, 20. Orange and blue, mixture of for coloured threads, 106. Orange and green, change by juxtaposition, 26. Orange and green, assortments of with white, 52 ; with black, 57 ; with grey, 61. Orange and grey, effects of juxtaposition of, 22. Orange and indigo, change by juxtaposition, 26. Orange and red, change by juxtaposition, 26. Orange and violet, assortments of with white, 52; with black, 57 ; with grey, 61. Orange and white, effects of their juxtaposition, 18. Orange and yellow, change by juxtaposition, 27; assortments of with white, 52 ; with black, 57 ; with grey, 61. Orange draperies, 171. Orange light, modifications produced by, 70. Orange-yellow, complementary to indigo, 16, 17, 21. P. Painters, Ancient, of Italy, their excellences, 87. Painting, Art of, 69 -, two systems of—-chiaro-’scuro and flat tints, ib .; on colouring in, 82 ; of aerial perspective, S3; harmony of the colours, 85, 95; simultaneous contrast of colours in, 87; modification of light, 89; application of the law of contrast, 97-99 ; distribution of colours, 101; painters of interiors, ib. ; imitation of coloured objects, 102 (see Gobelins Tapestry); difference of from tapestry, 111; relations existing between the subjects of, and the harmonies they admit of, 216 ; in the flat tints, 217; in chiaro-’scuro tapestries, carpets, mosaics, and coloured glass windows, corresponding to, 219 et seq. Panelling in the interior of a building, assortment of colour for, 163. Paper, printed or written, influence of light on, 137 ; contrast of tone, 13S. Paper-hangings, colours for printing, 118, 121; designs for, 121; simul¬ taneous contrast of colours in relation to, 121, 123, 124 ; borders, 123, 130-3 ; black ground, 125 ; various coloured grounds, 126 et seq.; me¬ tallic gilt ornaments, 126, 129 ; printed or written characters, 136. INDEX, 235 Park, definition of a, 187. Picture Galleries, on the interior decoration of, 150. Pictures in the interior of buildings, assortment of colours for, 145; as¬ sortment of, for the interior of a house, 162. Plantations, arrangements of, 193 ; lines of, ib. Plants, Ornamental, art of arranging according to the colours of their flowers, ISO, 181 ; assortments of, according to the harmonies of contrast and analogy, 1S2, 183 ; according to their foliage, 184 ; distribution of, 185; lines of, 1ST, 188; screens of, 188, 189; masses of, 1S9, 190; dif¬ ferent names of, when employed to form a landscape, forest, wood, park, grove, group, thicket, &c., 186, 187; isolated ones, 190 ; arrange¬ ment of into plantations, 193 et seq.; repetition of the same species, 194,195; variety of arrangement, 195; symmetry of parts, and their general harmony, 196. Portrait Painting, predominating colour in, 97 ; hints respecting the colour of the drapery, 1G9-171 ; results of dress and complexion applicable to, 178 ; dissimulating a tint of the complexion, ib. Position, varied, effects of, 75. Prepossessions, influence of, 225. Primary Colours, 25, 36; arrangements of, 63; binary mixture of, 104; mixture of, in such proportions that they do not become neutralized, 108. Printing in colours, 118 ; of calico patterns and paper hangings, 118, 121, 123 ; of carpets, 161. Pure colours, modifications of, 42, 45. R. Kays of solar light, 1. Kays, Coloured, juxtaposition of coloured bodies with, 24. Heading, on the assortment of colours for, by diffused daylight, 138. Ked, complementary to green, 3, 15, 16, 18, 20; placed in contact with orange-red, 24 ; its arrangement with a binary colour, 63. Red and black, effects of juxtaposition of, 20. Ked and blue, change of by juxtaposition, 27 ; assortments of with white, 52; with black, 56 ; with grey, 60; mixture of, for coloured threads, 105. Red and green, assortments of with white, 51 ; with black, 55 ; with grey, 59 ; mixture of, for coloured threads, 106. Red and grey, effects of the juxtaposition of, 21. Ked and violet, assortments of with white, 52 ; with black, 56 ; with grey, 61. Ked and white, effects of their juxtaposition, 18. Red and yellow, change by juxtaposition, 27 ; assortments of with white, 52 ; with black, 56 ; with grey, GO ; mixture of for coloured threads, 104. Reflection, laws of, 75. Kose-red draperies, 169. S. Savonnerte carpets, 102, 222. Scales of colours, definition of, 31; chromatic, 36 et seq.; their different tone 3 , 47 ; harmony of, 48 ; harmony of contrast of, ib.; of wool and silk employed in tapestry and carpet, 208. School of painters, 226. Screen of plants, 187, 188. 236 INDEX. Sculpture Galleries, on the interior decoration of, 150. Seats in the interior of buildings, assortment of colours for, 143. Secondary colours, 25, 26. Shrubs, small masses of, designated a bed, 187. Sight of colours, 198, 200. Silk employed in tapestry and carpets, effect of contrast upon the browns and lights of, 208. Simple colours, pass by juxtaposition into compound colours, 25. Simultaneous contrast of colours, 4, 8, 9, 10, 29 ; application of the law of, 34 ; in painting, 87 ; in calico-printing, 119, 121; principles of, 205. Skin, the coloured rays which may reflect upon the, 171. Skins, copper-coloured, black, or olive, assortment of dress suited for each, 177. Sofas, colour of, for harmonizing with the interior of a house, 157. Solar light, rays of, 1. Sombre colours, 50 ; proportion of to luminous ones, 66. Spotty, use of the term, 101. Stained glass windows, 113 et seq ., 147. (See Glass.) Stripes, Coloured, juxtaposition of, 24. Stuffs, Coloured, modifications of, 78, 79 ; in the interior of buildings, assort¬ ment of colours for, 143. Successive contrast of colours, 29. Sun, modifications produced by the light of the, 73. T. Tapestries, 102 ; of the Gobelins andof Beauvais,102,'104; qualities which they must possess, 111; difference of from the Beauvais, 113 ; principle of contrast in the production of, 109 ; difference of, from painting. 111; requisites for assimilating it to painting, 112 ; patterns for, ib. ; effect of contrast on the browns and lights of, 20S; principles involved in the colours of, 219 ; with human figures, 219, 224 ; for furniture, 220, 224 ; critical remarks on, 221; corresponding to paintings in chiaro-’scuro, 219 ; in flat tints, 224. Ternary assortments of colours, 50, 51, 59. Ternary combinations of colours complementary with black, 55; not com¬ plementary, 56. Textile fabrics, colour-printing on, 118. Thickets of trees, different kinds of, 187. Threads, coloured to make mixtures of, 102, 104 et seq.; red and yellow, ib.; red and blue, 105 ; yellow and blue, ib. ; mixture of complementary colours, 105. Tint of the complexion, how to dissimulate it in portrait painting, 178,179. Tone, contrast of, 4; experimental demonstrations, 7 ; the height of to be considered, 66 ; contrast of on written or printed paper, 13S. Tones, definition of, 34; of the same scale of colour, 47; of the scales of wool and silk, judging their equidistance, 209. Trees, assortment of in gardens according to the colour of their foliage, 184; distribution and planting of, in masses, 185 ; different terms applied to groups of, when employed to form a landscape, 186, 187; harmony between masses of, 192. INDEX. 237 V. Vandyke, masterpieces of, 99. Violet, complementary to greenish-yellow, 1C, 17, IS, 20; placed in juxta¬ position with scarlet-red, 24. Violet and black, effects of juxtaposition of, 21; combinations of, 55. Violet and blue, change by juxtaposition, 27. Violet and grey, effects of juxtaposition of, 22. Violet and red, change by juxtaposition, 26. Violet and white, effects of their juxtaposition, 19. Violet draperies, 170. Violet light, modifications produced by, 72. W. Wainscoting for the interior of buildings, 151; colour of, 155, 156. White, juxtaposition of coloured surfaces with, 18 ; modifications of, 19 ; assortments of different colours with, 50, 63; ternary assortments of colours not complementary with white, 51. White draperies, 171. White light, various modifications of, 75 et seq. Windows, of coloured glass, 113 et seq., 219, 223 ; in churches, 147, 149 of white glass, 148,149. Women’s clothing, colours of, 167 ; assortment of colours in, according to complexion, 177. Wood, in the interior of a building, assortments of colours for, 164. Wood, definition of a, 186. Wool, employed in tapestry and carpets, effect of contrast upon the browns and lights of, 208. Y. Yellow, placed beside’orange-yellow, 24 ; its arrangement with a binary colour, 63. Yellow and blue, changed by juxtaposition, 27; assortments of with white, 53; with black, 57; with grey, 62; mixture for coloured threads, 105. Yellow and green, assortments of with white, 53 ; with black, 57 ; with grey, 61. Yellow and grey, effects of juxtaposition of, 22. Yellow and violet, assortments of with white, 51; with black, 56 ; mixture of, for coloured threads, 107. Yellow draperies, 170. Yellow light, modifications produced by, 71. Yellowish-green, complementary to violet, 19. Yellowish-orange, complementary to indigo, 19. THE END. LOEBON : SAVIBB AND 1DWARB9, PRINTERS, CHANDOS STBEET, COVENT GABBEN. fteto writ ftri» (Etiitkis PUBLISHED BY GEORGE ROUTLEDGE AND CO. In 1 vol. demy 8vo, 3s. 6d. cloth gilt, or 3s. limp cloth. pURIOSITIES OF INDUSTRY.—THE APPLIED ''- /l SCIENCES. By Geobge Dodd, Author of “ Days at the Factories.” “ The title ‘ Cariosities of Industry ’ will pretty clearly explain itself. Many pro¬ cesses are curious without being novel, many are both novel and curious. Many reveal to us the store of strange and valuable things which science presents to those who know how to apply it in aid of industry ; many arise out of the discovery of new materials, and many more by new applications of old materials. Of all such are these ‘ Curiosities ’ composed.” Or each Treatise sold separately, bound in cloth limp, 6d. each. Contents or the Sebxes— viz.:— 1. Glass and its Manufacture. 9. Printing, its Modern Varieties. 2. Iron and its Manufacture. j 10. Cotton and Flax, a Contrast. 3. Wood and its Application. ! 11. Corn and Bread, what they Owe to 4. CaleulatingandEegisteringMachines. , Machinery. 5. India-Rubber and Gutta Pereha. 12. A Ship in the 19th Century. 6. Industrial Applications of Electricity. 13. Eire and Light—Contrivances for 7. Gold in the Mine, the Mint, and the \ their Production. Workshop. j 14. Wool and Silk, Pur and Feathers. 8. Paper, its Applications and its Novel- 15. The Chemistry of Manufactures. ties. ! 16. Steam Power and Water Power. In fcap. 8vo, price 2s. cloth extra. DUCATIONAL LECTURES delivered at St. Martins -Li Hall, Long Acre, London, by many distinguished Authors. “These Lectures are produced in the cheapest possible form, that the valuable information they contain may be brought within the reach of every person in the land; they are deserving the attention of every one who takesgan interest in the now all-important subject of education. They have been published with and under the sanction of the Council of the Society of Arts.” In royal 32mo, price 8d. cloth, strongly bound; or in roan plain, 3d. ; or in roan with gilt edges, Is. JOHNSON’S POCKET DICTIONARY OF THE ^ ENGLISH LANGUAGE. Improved Edition, with the addition of three thousand words. In 1 vol. fcap. 8vo, price 2s. cloth extra. DOMESTIC COOKERY. By Mrs. Rundell. A New Edition of this Popular Book. Formed upon Principles of Economy, and adapted to the U3e of Private Families. With Ten Illustrations. New Books and New Editions. In 1 vol. fcap. 8vo, price 5s. cloth, 600 pp. THE TREASURY OF MEDICINE; or, Every One’s ~L Medical Guide. By John James, M.D. <£ This is a new and valuable work, containing directions on the diseases of men, women, and children; on bathing, diet, regimen for the sick, &c.; on climate and mineral waters for invalids and travellers ; with especial advice to emigrants of all classes; forming a book of reference invaluable to clergymen, parents, English resi¬ dents abroad, captains of ships, emigrants. It embodies the professional experience of full forty years; and the contents are the results of not only mere reading, and of close continued attention to all proposed improvements in medical art and science, but also of a practical bed-side experience, accumulated both in public and private practice during many years, the writer having served as physician to three dispen¬ saries and to two hospitals.’* In fcap. 8vo, price Is. 6d, cloth extra. H OME BOOK OF HOUSEHOLD ECONOMY; or, Domestic Hints for Persons of Moderate Income. Containing useful directions for the proper Labours of the Kitchen, the House, the Laundry, and the Dairy. The Eighth Thousand, Revised and En¬ larged. In demy 18mo, price Is. cloth, or Is. 6d. roan embossed. M ASTER’S READY RECKONER, The Ninth Edition, Revised and Improved, with additional Tables of Interest, Com¬ mission Wages, Per Centage, and Profit, Time, Weights, and Measures. By John Heaton. “ The present editor has most carefully inspected the whole work, and believes it to be perfect in every calculation; it may therefore be relied upon as a most correct and useful work.” In royal 32mo, cloth, Gd., or roan, Is. rPHE TRADESMAN’S READY CALCULATOR, for J- Masons, Plasterers, Slaters, Painters, &c. The chief design of this work is to furnish, at a cheap rate, an easy method of calculating the square contents of all kinds of work, where measurements are taken. Tables of wages are also added. In fcap. 8vo, price Is. 6d. cloth. \ NEW LETTER WRITER, for the use of Ladies and LA Gentlemen ; embodying letters on the simplest matters of life, and on various subjects, with applications for Situations, &c. “ In the present day, when education is so rapidly progressing, a superior work on the subject of ‘ Letter Writing’ is obviously needed. The old works of the kind were obsolete in diction, exaggerated, and unnatural—frequently to a ludicrous excess—in their thoughts. And the topics upon which they professed to give speci¬ mens were not well chosen. A writer, in a recent number of Parker’s ‘ National Miscellany,’ has expressed a hope that every Englishman will soon be able to write his own name, and that ‘ putting one’s mark’ may be confined to the backs of sheep. The editor of this present little manual ventures to hope for a still more onward ‘ march of intellect,’ when the art of writing a plain, straightforward, and gram¬ matical letter, whether on business or friendship, shall be a matter of course.” London ; GEORGE ROUTLEDGE & Co., Fabrtngdon-Street. NO 1488 C52 1857 ThJ, Chevreul, The laws of contrast of colour »in mill llllll 3 3125 00161 BKS «■ E. (Mlc = and the! 3567