CHAPTER VIII.
_On the Application of the Law of Contrast to the Hypothesis 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, are 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 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 element yellow in common, lose it by juxtaposition. _The orange appears redder, and the green bluer._
2. _Orange and Indigo._—These colours having the element 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 element 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._
Plate 6.
1. _Orange and Red._—The orange loses red, and appears yellower; the red becomes bluer, to differ as much as possible from the orange.
[Illustration: PLATE VI.]
2. _Violet and Red._—The violet loses red, and appears 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 appears 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 appears yellower; the blue becomes redder, to differ as much as possible from the green.
7 _Violet and Blue._—The violet loses blue, and appears 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.—_Two Simple Colours._ (See 6, 7.)
1. _Red and Yellow._—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 appears 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 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._
1. _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 elements 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 incline to blue rather than to yellow.
SECTION II.
ON THE DISTINCTION BETWEEN SIMULTANEOUS, SUCCESSIVE, 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 experiments 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 that phenomena of modification which 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 phenomena observed when the eyes having looked for some time at one or more coloured objects, perceive, after having 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 understanding of the phenomena which maybe called _mixed contrast_; 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.
For want of this distinction, one of the branches of optics most fertile in applications, has not been treated with the clearness and precision which are necessary to show its importance to those who have not experimented upon it.
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 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 mixture 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 shut the left eye, and to look at the colour B with the right eye; when the sensation perceived 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 perceived, 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 sheet 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 repeated several times, 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 complementary 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 right eye, which has not been modified by the sight of red, being opened, it sees yellow, and it is possible that this yellow may appear more orange than it is really.
87. _If the left eye_ | _and had_ | _the latter would_ _had first seen_ | _afterwards 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.
116. I should observe that all these colours, at least to my eyes, did not undergo equally intense or equally continuous modifications. For instance, the modification 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 than that of orange and blue. The modification produced by the successive view of red and green, of green and red, 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 mention under a special name the phenomenon which I call _mixed contrast_, as it explains certain facts remarked by dealers in coloured fabrics, as well as the inconvenience felt by painters, who, wishing to produce an exact imitation of their models, look at them so long as to be unable to perceive their tones and modifications. I will mention 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; because 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 purchaser, 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 succession, 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 sufficiently 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.
PART THE SECOND.
ON THE APPLICATION OF THE LAW OF SIMULTANEOUS CONTRAST OF COLOURS.
INTRODUCTION.
120. Before entering into the details of these applications, 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 their modifications by the aid of diagrams. 3. A classification of the harmonies of colours. 4. A view of some arrangements of the primary colours with white, black, and grey.
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 ambiguity, 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 receiving from white, which _lowers_ its tone, or of black, which _heightens_ it.
124. The word SCALE will be applied to the assemblage 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 (149).
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, &c. 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 intensity for receiving black,” is absolutely essential to this definition; 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_. (150.) _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 _broken_ tones.
128. Artists, and especially painters and dyers, admit that the mixture of three primary colours, in a certain proportion, gives black; hence, when these three colours are so mixed that two predominate, black will result, formed from the union of the whole of the colour, which is in small quantity, within suitable proportions 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, Chromatometers, &c., for representing either by numbers or a rational nomenclature, colours and their modifications. They are generally founded on these three propositions:—1. 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 we know of no substance which exhibits pure colour; that is, which reflects only one kind of coloured rays, whether pure red, pure yellow, or pure blue. And since it is impossible to procure pure colouring 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?
[Illustration: PLATE VII.]
These chromatic tables, &c., point out mixtures which do not produce the results deducible from the principles on which they are said to be based.
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 brilliancy to the natural violet, green and orange colours of objects. This result would be explained by admitting 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 respective colours of these materials approach each other. For example, a mixture of blue and red inclines more to violet than a mixture of blue and yellow inclines to green, and that of red and yellow inclines still more to orange.
134. 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 complementary to each other, I have devised the following diagram (Plate 7). From a centre, _c_, I describe two circumferences, _y_ Y. I divide each of these by means of three rays, _c a_, _c b_, _c d_, into arcs of 120 degrees each. I divide the portion of each ray comprised between the two circles _y_ Y 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 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 surface _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 unequal lightness of the colours.
136. If each arc of 120° be divided into two of 60° and if radii pass through the points of division, beginning at _y_, there will be represented twenty tones of the orange, green, and violet scales, the colours at the extremities of each diameter being complementary to one another. Each arc of 60° might be divided 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.
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 _k_ 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 seventy-two scales just described. The number may be increased indefinitely, 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. Imagine a quadrant whose radius is equal to that of the circle, and arranged so as to turn upon an axis perpendicular to the plane of the circle. Divide this quadrant, 1st, by concentric arcs _y yʹ_, which coincide with the circles denoted by the same letters; 2nd, by ten radii, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10. Divide each of these radii into twenty parts, representing twenty tones, corresponding to the tones of the scales represented on the circle.
143. I suppose that the tenth radius comprises the gradations of normal black, covering 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, 8, 9, is formed of the mixture of black with the colour of any of the scales that the circle contains, and in such a proportion that the normal tone 15 of that scale is represented by the unit of surface covered with 1, or ¹⁰/₁₀ of red.
144. The tone 15 of the scale of the
1st Radius = ⁹/₁₀ of Red + ¹/₁₀ of Black. 2nd ” = ⁸/₁₀ ” + ²/₁₀ ” 3rd ” = ⁷/₁₀ ” + ³/₁₀ ” 4th ” = ⁶/₁₀ ” + ⁴/₁₀ ” 5th ” = ⁵/₁₀ ” + ⁵/₁₀ ” 6th ” = ⁴/₁₀ ” + ⁶/₁₀ ” 7th ” = ³/₁₀ ” + ⁷/₁₀ ” 8th ” = ²/₁₀ ” + ⁸/₁₀ ” 9th ” = ¹/₁₀ ” + ⁹/₁₀ ”
These proportions relate to the effect of the mixtures upon the eye, and not to the material quantity of the red and black substances.
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 circle, whose plan comprehends the pure colours; the central space, black; and the intermediate space the pure colours, broken by the various proportions of black.
146. The 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. 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 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—1. _The Pure Colour never leaves its Scale._—The modification is in the direction of the radius of the circle—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 numbers. Thus admitting, with painters and dyers, that there are only three primary colours, and that by combining these two by two, we obtain all the pure complex colours; and by combining them in threes, all the broken 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 all 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 complementary with the contiguous colour. In fact, if there is no difficulty when the result is that of the non-complementary mixture with a simple colour, red, yellow, and blue, with a binary colour, orange, green, violet (using the language of painters, 76), 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, neutralises it.
153. _Examples._—1. Orange being added as a complementary to green, neutralises a portion of its blue, and consequently makes it appear less blue or more yellow.
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 subtracting from the binary colour a portion of its simple colour which is identical with that contiguous to it. Thus:—
1. Blue subtracted from Green, makes it appear more Yellow. 2. Blue ” ” Violet ” ” Red. 3. Red ” ” 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 developed 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 reproduce 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. 1. _That it represents all the Modifications resulting from the Mixture of Colours._—Thus any colour lowered by white and deepened with black may, retaining 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.
157. 2. Pure colours, by their mutual modifications, may produce an infinite variety of hues; for between two adjacent hues we may insert as many as we desire.
158. 3. The normal tone of a pure colour represented by a quantity equal to 1, covering the unit of surface, is the commencement of the normal tones and scales proceeding towards black; these normal tones being represented 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. _It affords the means of knowing the complementaries of every colour, since the names written 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 yellow_; 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 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 what 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 distinguishes 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 who use coloured materials of a definite size, 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 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, derives pleasure from looking 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 agreeable sensation, especially if the tones have equal and sufficiently numerous intervals; for example, from eighteen to thirty.
169. Third Case. _View of Different Colours, belonging 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 agreeable; 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, belonging 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 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 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 harmonies 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 approximating. 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 simultaneous 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.
SECTION IV.
_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, &c., will find advantage in consulting them.
175. The _ground_, as well as the interval between the colours, having influence upon their effect, all my observations were made with white, black, grey, and coloured circles, ⁴/₁₀ of an inch in diameter, separated by intervals of ⁴/₁₀ of an inch; thirteen circles arranged in a straight line forming a series.
176. 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.
177. The colours which have been under my notice are red, orange, yellow, green, blue, violet. Their differences in regard to brilliancy are so great as to admit of their being divided into two groups, one comprising red, orange, yellow, and bright green, the other blue and violet, which, with the same depth of tone, have not the brilliancy of the former. I shall call the first group _luminous colours_, and the second _sombre colours_. But the deep and broken tones of the _luminous scales_ may in many cases be assimilated to the sombre group, as the light tones of blue and violet may sometimes be employed as _luminous_ colours.
ARTICLE I.
_Colours with White._
Plate 8.
A. _Binary Assortments._
178. All the primary colours gain by their juxtaposition with white, but the binary arrangements which result from them are not equally agreeable; and it is to be remarked that the depth of tone of a colour has a great influence upon the effect of its assortment with white.
The binary assortments in the order of their greatest beauty, are as follows:—_light blue_ and white, _rose_ and white, _deep yellow_ and white, _bright green_ and white, _violet_ and white, _orange_ and white.
Dark blue and dark red produce, with white, too strong a contrast of tone to allow of their assortment being as agreeable as that of their light tones. On the contrary, yellow being a light colour, we must take the normal or deepest tone of yellow to produce its most beautiful effect. Dark green and violet contrast too much in tone with white for their combination to be as agreeable as those which are made with the light tones of these colours. The objection which can be made to the combination of orange and white is that of too much brilliancy; yet I should not be surprised to find that many persons preferred it to that of violet and white.
B. _Tertiary Assortments of Colours complementary to each other with White._
179. It is to me impossible to establish an order of beauty among binary combinations of primary complementary colours. I shall therefore only describe the effect of white interposed between the binary complementary assortments, or between each of the complementary colours.
[Illustration: PLATE VIII.]
180. 1. _Red and Green_ are of all complementary colours the most equal in depth; for red, as regards its brilliancy, is midway between yellow and blue; and in green these two extremes are united. 2. The arrangement, white, red, green, white, &c., is not decidedly superior to the preceding, at least when the colours are not deep. 3. The arrangement white, red, white, green, white, &c., seems to me inferior to the preceding.
181. 1. _Blue and Orange_ are more opposed to each other than red and green, because the least brilliant colour blue, is separated, while the most brilliant are combined in orange. 2. The arrangement, _white, orange, blue, white_, &c., is agreeable. 3. The arrangement, _white, orange, white, blue, white_ &c., is also agreeable.
182. 1. _Yellow and Violet_ form an arrangement which, as regards depth of tone, is most distinct, since the least intense or lightest colour, the yellow, is separated from the others. Because of this great contrast of tone, the deep, but pure, greenish-yellow combines better with light violet, than light yellow and deep violet. 2. The arrangement, _white, yellow, violet, white_, &c., appears to me inferior to the preceding arrangement (1). 3. The arrangement, _white, yellow, white, violet, white_, &c., seems to me inferior to 2.
C. _Ternary Assortments of Colours not complementary with White._
183. 1. Red and orange do not accord well. 2. The arrangement, _white, red, orange, white_, &c., is scarcely preferable. 3. The arrangement, _white, red, white, orange, white_, &c., is not so bad as the preceding, because white being favourable to all the colours, its interposition between the colours which injure each other, can only produce an advantageous effect.
184. _Red and Yellow_ accord pretty well, especially if the red is purple-red rather than scarlet, and the yellow rather greenish than orange. 2, The arrangement, white, red, yellow, white, is preferable to the preceding. 3. The arrangement _white, red, white, yellow, white_, is still better.
185. 1. _Red and Blue_ accord passably, especially if the red incline rather to scarlet than to crimson. Deep tones are preferable to light ones. 2. The arrangement _white, red, blue, white_, &c., is preferable to 1. 3. The arrangement _white, red, white, blue, white_, is preferable to the second.
186. 1. _Red and Violet_ do not accord well, yet they are found in some natural productions, as the sweet pea. 2. The arrangement _white, red, violet, white_, is not so bad as the preceding. 3. The arrangement _white, red, white, violet, white_, is preferable.
187. 1. _Orange and Yellow_ accord incomparably better than red and orange. 2. The arrangement _white, orange, yellow, white_, is agreeable. 3. The arrangement _white, orange, white, yellow, white_, is not so good as 2, and perhaps 1, because there is too much white.
188. 1. _Orange and Green_ do not accord well. 2. The arrangement _white, orange, green, white_, is preferable to 1. 3. The arrangement _white, orange, white, green, white_, is perhaps preferable to 2.
189. 1. _Orange and Violet_ accord passably, yet not so well as orange and green; the contrast, in the latter case, is greater than in the arrangement orange and violet. 2. The arrangement _white, orange, violet, white_, &c., is preferable to the preceding. 3. The arrangement _white, orange, white, violet, white_, &c., is preferable to 2.
190. 1. _Yellow and Green_ form an agreeable combination. 2. The arrangement _white, yellow, green, white_, &c., is still more agreeable. 3. The arrangement _white, yellow, white, green, white_, &c., is inferior to the preceding, and perhaps to the first. The inferiority of 3 seems to me to be caused by too much light for the _green_.
191. 1. _Yellow and Blue._ The arrangement of _yellow_ and _blue_ is more agreeable than that of _yellow_ and _green_, but it is less lively. 2. The arrangement _white, yellow, blue, white_, &c., is perhaps preferable to the preceding. 3. The arrangement _white, yellow, white, blue_, &c., is perhaps inferior to the preceding.
192. 1. _Green and Blue_ produce an indifferent effect, but better when the colours are deep. 2. The arrangement _white, green, blue, white_, &c., is preferable. 3. The arrangement _white, green, white, blue, white_, &c., has a still better effect, because the light is more equally distributed.
193. 1. _Green and Violet_, especially when light, form a combination preferable to the preceding, _green_ and _blue_. 2. The arrangement _white, green, violet, white_, &c., is not decidedly superior to the preceding. 3. The arrangement, _white, green, white, violet, white_, &c., is not decidedly superior to it.
194. 1. _Blue and Violet_ accord badly. 2. The arrangement, _white, blue, violet, white_, &c. is scarcely preferable to the preceding (1). 3. The arrangement _white, blue, white, violet, white_, &c., is not so bad as the preceding (2).
ARTICLE II.
_Colours and Black._
Plate 9. (Frontispiece.)
195. I do not know whether the use of black for mourning, prevents the use of it, in numberless cases, where it would produce excellent effects; it may be combined most advantageously, not only with sombre colours to produce the harmony of analogy, but also with light and brilliant colours to produce the harmony of contrast.
196. Chinese artists appear to have made excellent use of it, for I have often seen furniture, painting, ornaments, &c., where it has been most judiciously employed. I recommend those artists for whom this paragraph is particularly designed, to attend to the following observations, not doubting that many will be profitable to them.
A. _Binary Combinations._
197. No combination of primary colours with black is disagreeable, but there exists among these a generic difference of harmony, which is not shown, at least to nearly the same degree, in the binary combinations of white with the same colours. In fact the brilliancy of white is so predominant, that whatever may be the difference of lightness or brilliancy observed between the various associated colours, there will always be the harmony of contrast, according to what has been said (44-52) of the influence of white in raising the tone and augmenting the intensity of the colour adjacent to it.
198. If the binary combinations of black be examined in this point of view, it will be seen that the deep tones of all the scales, and even of the blue and violet scales (which are not, properly speaking, deep), form with it harmonies of analogy and not of contrast. So likewise do the unbroken tones of the _red, orange, yellow-green_ scales, and the very light tones of the violet and blue scale. We may add, according to what has been said (55), that the combinations of _black_ with sombre colours, such as _blue_ and _violet_, whose complementaries, orange and _greenish-yellow_, are luminous, may diminish the contrast of tone if the colours be juxtaposed with _black_ or one not far from it, and in this case the _black_ loses much of its vigour.
199. _Blue_ and _Black, Violet_ and _Black_, make combinations which may be employed successfully when only dark colours are required. The first is superior to the second.
200. Light combinations which exhibit the harmonies of contrast, appear to me in the order of beauty thus:—
_Red_ or _Rose_ and _Black_, _Orange_ and _Black, Yellow_ and _Black_, lastly, _Bright Green_ and _Black_. As to yellow, I repeat that it must be brilliant and intense, inasmuch as black tends to impoverish its tone.
B.—_Ternary Combinations of Colours mutually Complementary with Black._
201. 1. _Red, Green_, &c. 2. _Black, Red, Green, Black_, &c. This arrangement being quite different from the former, it is difficult to decide respecting their comparative beauty. 3. _Black, Red, Black, Green, Black_, &c., appear to me inferior to the preceding, because there is too much black.
202. 1. _Blue, Orange_, &c. 2. _Black, Blue, Orange, Black_. I prefer the first to the second; the proportion of dark colour being too strong relatively to the _orange_. 3. _Black, Blue, Black, Orange, Black_, &c. This pleases me less than the first.
The effect of _black_ with _blue_ and _orange_ is inferior to that of _white_.
203. 1. _Yellow, Violet_, &c. 2. _Black, Yellow, Violet_, &c. 3. _Black, Yellow, Black, Violet, Black_, &c. The second is superior to the third, because the proportion of sombre colours with the _yellow_ is too strong in the latter. The first appears to me superior to the second.
C.—_Ternary Combinations of Colours not Complementary with Black._
204. 1. _Red, Orange_, &c. 2. _Black, Red, Orange, Black_, &c. 3. _Black, Red, Black, Orange, Black_, &c. As orange and red injure each other, there is an advantage in separating them by black. The third arrangement is preferable to the second; and both are preferable to those in which _black_ is replaced by _white_.
205. 1. _Red, Yellow_, &c. 2. _Black, Red, Yellow, Black_. 3. _Black, Red, Black, Yellow, Black_, &c. The two last arrangements appear to me superior to the first, and many persons would prefer them to the arrangement in which _white_ replaces _black_. I cannot too strongly recommend the arrangement 2 and 3 to artists, for whom these observations are especially designed.
206. 1. _Red, Blue_, &c. 2. _Black, Red, Blue, Black_. 3. _Black, Red, Black, Blue, Black_, &c. No. 2 is preferable to No. 3, because there are too many sombre colours in the latter, and because these differ too much from the _red_. The effect of _black_ upon the binary arrangement, _red_ and _blue_, is inferior to that of _white_.
207. 1. _Red, Violet_, &c. 2. _Black, Red, Violet, Black_, &c. 3. _Black, Red, Black, Violet, Black_, &c. The _red_ and _violet_ injure each other, it is therefore advantageous to separate them by _black_; but the latter does not produce so good an effect as _white_. It is difficult to say whether No. 3 is preferable to 2; because, if there be in the latter _red_ near _violet_, this defect is more than compensated in 3, by the predominance of sombre colours over the _red_.
208. 1. _Orange-Yellow_, &c. 2. _Black, Orange-Yellow_, &c. 3. _Black, Orange, Black, Yellow, Black_, &c. The _orange_ and _yellow_ being very luminous, the _black_ allies itself to them very well in the arrangement 2 and 3; and if the arrangement, _white, orange, yellow, white_, be preferred to No. 2, I think that in the arrangement 3, the _black_ produces a superior effect to the _white_.
209. 1. _Orange, Green_, &c. 2. _Black, Orange, Green_, &c. 3. _Black, Orange, Black, Green, Black_, &c. _Black_ combines well with _orange_, and with _bright green_. In like manner it combines well with _orange_ and _yellow_. If, in the arrangement 2, _white_ be preferred to _black_, I think it cannot be in 3. I recommend to artists the combination of _black_ with the binary arrangements _orange_ and _yellow, orange_ and _green_.
210. 1. _Orange, Violet_, &c. 2. _Black, Orange, Violet, Black_, &c. 3. _Black, Orange, Black, Violet, Black_, &c. _Black_ does not combine so well as _white_ with _orange_ and _violet_, because the proportion of dark colours relatively to _orange_, a very vivid colour, is too great.
211. 1. _Yellow, Bright Green_, &c. 2. _Black, Yellow, Green, Black_, &c. 3. _Black, Yellow, Black, Green, Black_, &c. _Yellow_ and _light green_ being luminous colours, _black_ combines very well with them; and if in the arrangement 2 the effect of _white_ be preferred to that of _black_, I think that it cannot be in the arrangement 3.
212. 1. _Yellow, Blue_, &c. 2. _Black, Yellow, Blue, Black_, &c. 3. _Black, Yellow, Black, Blue, Black_, &c. If the arrangement 2 be preferable to 3, I think it inferior to 1. The _black_ does not appear to combine so well as the white in the group _yellow_ and _blue_.
213. 1. _Green, Blue_, &c. 2. _Black, Green, Blue, Black_, &c. 3. _Black, Green, Black, Blue, Black_, &c. Although _green_ and _blue_ do not well accord, yet the combination with _black_ is not decidedly advantageous. Because of the augmentation of the proportion of sombre colours, the _white_ has a superior effect to the _black_.
214. 1. _Green, Violet_, &c. 2. _Black, Green, Violet, Black_. 3. _Black, Green, Black, Violet, Black_, &c. If the _black_ unite better with _green_ and _violet_ than with _green_ and _blue_, yet these ternary combinations are inferior to the binary combinations; and inferior to the ternary combination where it is replaced by _white_.
215. 1. _Blue, Violet_, &c. 2. _Black, Blue, Violet, Black_, &c. 3. _Black, Blue, Black, Violet, Black_, &c.
216. Although _blue_ and _violet_ are colours which do not accord well, and although there is an advantage in separating them, yet it must be remembered that _black_ in isolating them, does not relieve their sombre colour, but, on the other hand, the harmony of the arrangements of 2 and 3 is more agreeable as a harmony of analogy than the harmony of contrast presented by _white_ with the same colours. Thus there are cases in which the assemblage of _black, blue_, and _violet_, may be advantageous, when it is desired to produce diversified, but not striking effects.
ARTICLE III.
_Colours with Grey_.
Plate 10.
[Illustration: PLATE X.]
217. All the primary colours gain purity and brilliancy by the proximity of grey; yet the effects are far from being like or even analogous to those which result from the proximity of the same colours with white. This will not create surprise, if it be remembered that while white preserves the character of each colour and exalts it by contrast, it can never be taken for a colour properly so called; grey, on the contrary, may be; it happens that the latter makes with the most sombre colours, as blue, violet, and deep tones in general, assortments which belong to the harmonies of analogy; while, with colours naturally brilliant, such as red, orange, yellow, and the light tones of green, they form analogies of contrast. But, although white contrasts more with sombre colours than with those that are naturally luminous, there is not observed between white and those two kinds of colours the difference observable between grey and the same colours. This result confirms what I have said of the binary combinations of black. (203.)
A.—_Binary Combinations._
218. _Grey and Blue, Grey and Violet_, form arrangements of which the harmony of analogy is agreeable, yet less so than that of _black_ with the same colours.
219. _Grey and Orange, Grey and Yellow_, _Grey and Bright Green_, form equally agreeable arrangements of harmony of contrast; perhaps they are less so than those in which _grey_ is replaced by _black_.
220. _Grey and Rose_ are a little dull and inferior to _Black and Rose_. All the binary arrangements of _grey_, except, perhaps, that of _orange_, are inferior to those of _white_.
B.—_Ternary Combinations of Complementary Colours with Grey_.
221. _Red_, _Green_, _&c_.—1. _Red, Green_, &c. 2. _Grey, Red, Green, Grey_, &c. 3. _Grey, Red, Grey, Green, Grey_, &c. 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_, &c. 2. _Grey, Blue, Orange, Grey_. 3. _Grey, Blue, Grey, Orange, Grey_, &c. I prefer the first arrangement to the two others.
223. _Yellow and Violet._—1. _Yellow, Violet_, &c. 2. _Grey, Yellow, Violet, Grey_, &c. 3. _Grey, Yellow, Grey, Violet, Grey_, &c. Although the arrangements 2 and 3 are lighter than the arrangements in which _grey_ is replaced by _black_, yet the binary arrangement appears to me preferable to the ternary.
C.—_Ternary Assortments of Colours not Complementary to each other with Grey._
224. _Red and Orange._—1. _Red, Orange_, &c. 2. _Grey, Red, Orange, Grey_, &c. 3. _Grey, Red, Grey, Orange, Grey_, &c. The arrangements 2 and 3 are preferable to the binary. The third is preferable to the second. In short, the grey produces, with _red_ and _orange_, a better effect than _white_, but the effect is inferior to that of _black_.
225. _Red and Yellow._—1. _Red, Yellow_, &c. 2. _Grey, Red, Yellow, Green_, &c. 3. _Grey, Red, Grey, Yellow, Grey_, &c. Although the grey combines well with the _red_ and the _yellow_, it has not so decidedly advantageous an effect as _black_ in the binary arrangement.
226. _Red and Blue._—1. _Red, Blue_, &c. 2. _Grey, Red, Blue, Grey_, &c. 3. _Grey, Red, Grey, Blue, Grey_, &c. The arrangement 2 is preferable to 3. I dare not say to 1. The effect of grey is inferior to that of _white_.
227. _Red and Violet._—1. _Red, Violet_, &c. 2. _Grey, Red, Violet, Grey_, &c. 3. _Grey, Red, Grey, Violet, Grey_, &c. The assortment 3 appears to me superior to 2, and the second to the first; but it is difficult to say whether _grey_ is superior to _black_. I am certain it is superior to _white_.
228. _Orange and Yellow._—1. _Orange, Yellow_, &c. 2. _Grey, Orange, Yellow, Grey_, &c. 3. _Grey, Orange, Grey, Yellow, Grey_, &c. The assortment 3 appears to me preferable to 2; the harmony of contrast is less intense than with _black_. The assortment 3 is, perhaps, superior to the assortment of _white, orange, white, yellow, white_.
229. _Orange and Green._—1. _Orange, Green_, &c. 2. _Grey, Orange, Green, Grey_, &c. 3. _Grey, Orange, Grey, Green, Grey_, &c. Grey combines well with _orange_ and _green_, but it does not contrast so agreeably as _black_ or _white_.
230. _Orange and Violet._—1. _Orange, Violet_, &c. 2. _Grey, Orange, Violet, Grey_, &c. 3. _Grey, Orange, Grey, Violet, Grey_, &c. The binary assortment appears to me preferable to the other two. The assortment 2 is preferable to 3. If the _grey_ is a little dull with _orange_ and _violet_, it has not the same disadvantage as _black_, in causing too great a predominance of sombre colour.
231. _Yellow and Green._—1. _Yellow, Green_, &c. 2. _Grey, Yellow, Green, Grey_, &c. 3. _Grey, Yellow, Grey, Green, Grey_, &c. _Grey_ combines well with _yellow_ and _green_, but the assortments 2 and 3 are a little dull, and inferior to those in which _black_ replaces _grey_.
232. _Yellow and Blue._—1. _Yellow, Blue_, &c. 2. _Grey, Yellow, Blue, Grey_, &c. 3. _Grey, Yellow, Grey, Blue, Grey_, &c. The two assortments, two and three, are inferior to the first. The _grey_ is heavy to _yellow_ and _blue_; its effect is inferior to that of _white_, and perhaps also to that of _black_.
233. _Green and Blue._—1. _Green, Blue_, &c. 2. _Grey, Green, Blue, Grey_, &c. 3. _Grey, Green, Grey, Blue, Grey_, &c. _Grey_, in its combination with _green_ and _blue_, has not the same objection as _black_, but it has an inferior effect to _white_.
234. _Green and Violet._—1. _Green, Violet_, &c. 2. _Grey, Green, Violet, Grey_, &c. 3. _Grey, Green, Grey, Violet, Grey_, &c. _Grey_ is not employed advantageously with _green_ and _violet_, it is inferior to _white_ in the ternary arrangements, and perhaps I should also give preference to _black_.
235. _Blue and Violet._—1. _Blue, Violet_, &c. 2. _Grey, Blue, Violet, Grey_, &c. 3. _Grey, Blue, Grey, Violet, Grey_, &c. The remarks made (218) in the assortment of _black_ with _blue_ and _violet_ are applicable to the arrangement with grey, taking into account the difference of tone which exists between _grey_ and _black_.
_Recapitulation._
236. I will now give a summary of the observations which appear the most striking on reading the foregoing paragraphs, premising, however, that I do not pretend to establish laws fixed upon scientific principles, but to state general propositions which express my own peculiar taste.
237. 1st. _In the harmony of contrast the complementary arrangement is superior to every other._
The tones must be as nearly as possible of the same depth to produce the finest effect. The complementary arrangement in which white associates most advantageously, is that of blue and orange, and that of yellow and violet is the least advantageous.
238. 2nd. _The Primaries, Red, Yellow, and Blue associated in pairs assort better together, as a harmony of contrast, than an arrangement formed of one of these primaries, and of a binary colour in juxtaposition with it, having the same primary as one of its elements._
_Examples._
Red and Yellow accord better than Red and Orange. Red and Blue ” ” Red and Violet. Yellow and Red ” ” Yellow and Orange. Yellow and Blue ” ” Yellow and Green. Blue and Red ” ” Blue and Violet. Blue and Yellow ” ” Blue and Green.
239. 3rd. _The arrangement of Red, Yellow, or Blue with a binary colour containing the former, contrasts the better, as the simple colour is essentially more luminous than the binary._
Whence it follows, that in this arrangement, it is an advantage for the red, yellow, or blue to be of lower tone than the binary colour.
_Examples._
Red and Violet accord better than Blue and Violet. Yellow and Orange ” ” Red and Orange. Yellow and Green ” ” Blue and Green.
240. 4th. _When two colours accord badly together, it is always advantageous to separate them by White._
In this case it is more advantageous to place each colour next to white, than in an assortment where the two colours are together beside white.
241. 5th. _Black never produces a bad effect when it is associated with two luminous colours. It is therefore often preferable to White, especially in an assortment where it separates the colours from each other._
_Examples._
1. Red and Orange.
Black is preferable to white in the arrangements 2 and 3 of these two colours. 2. Red and Yellow. 3. Orange and Yellow. 4. Orange and Green. 5. Yellow and Green.
Black, with all these binary assortments, produces harmony of contrast.
242. 6th. _Black in combination with sombre colours, such as blue and violet, and with broken tones of luminous colours, produces harmony of analogy, which, in many instances, may have a good effect._
The harmony of analogy of black, associated with blue and violet, is preferable to the harmony of contrast of the assortment white, blue, violet, white, &c., the latter being too crude.
243. 7th. _Black does not accord so well with two colours, one of which is luminous, the other sombre, as when it is associated with two luminous colours. In the first instance the combination is so much the less agreeable as the luminous colour is more brilliant._
With all the following assortments Black is inferior to White. 1. Red and Blue. 2. Red and Violet. 3. Orange and Blue. 4. Orange and Violet. 5. Yellow and Blue. 6. Green and Blue. 7. Green and Violet.
With the assortment yellow and violet, if it is not inferior to white, it produces only a mediocre effect.
244. 8th. _Although Grey never produces exactly a bad effect in its association with two luminous colours, yet in most cases its assortments are dull, and it is inferior to Black and White_.
Among the assortments of two luminous colours, there are scarcely any besides those of red and orange with which grey associates more happily than white. But it is inferior to it, as also to black, in the arrangements red and green, red and yellow, orange and yellow, orange and green, yellow and green. It is also inferior to white, with yellow and blue.
245. 9th. _Grey, in combining with sombre colours, such as Blue and Violet, and with broken tones of luminous colours, produces harmonies of analogy, which have not the vigour of those with black; although the colours do not combine well together, it has the advantage of separating them from each other._
246. 10th. _When Grey is associated with two colours, one of which is luminous the other sombre, it will perhaps be more advantageous than White, if this produces too strong a contrast of tone; on the other hand, it may be more advantageous than Black, if that increases too much the proportion of sombre 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, &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 assortment white, blue, white, violet, white, &c., is preferable to the assortment white, blue, violet, white, &c., because the separation of the brilliant from the sombre is more equal in the first than in the second. I should add that this is somewhat more symmetrical as to the position of the two colours, and the principle of symmetry influences our judgment of things more than is generally recognised. It is also in conformity with the above, that the assortment black, red, black, orange, black, &c., is preferable to the assortment black, red, orange, black, &c.
250. Some remarks appear to me also necessary to prevent false deductions from the above propositions. In the preceding examples, the colours, including white, black, and grey, are supposed to occupy an equal extent of surface, and to be placed at equal distances apart, for without these conditions the results will be different; for example, I have preferred the assortment white, red, white, yellow, white, to the assortment white, red, yellow, white. There are some cases in which the latter is preferable to the former, as in the arrangement of flowers in gardens, especially yellow and rose flowers, which present less coloured surface than the white flowers with which they are associated.
251. I have spoken of the good effects of black and green separated, and I may add that green designs upon a black ground are also agreeable; but it does not follow that black lace upon a green stuff will have a good effect, at least on the optical quality of black, for this acquires a rusty tint, which resembles a faded colour.
252. The more colours are opposed, the easier it is to assort them; because they do not experience by their mutual juxtaposition, any modification which renders them disagreeable, as generally happens to colours which are very nearly alike. Must we then conclude that with two colours which have in this case been indicated to an artist to be employed, with some liberty to modify them, he should endeavour to increase the effect of contrast rather than that of analogy? Certainly not; for frequently the latter is preferable to the former. For example:—Take orange-red and a pure red, instead of increasing the yellow in the orange-red, or of giving a violet hue to the red, it sometimes will be preferable to incline towards the harmony of scale or of hue, by endeavouring to make the orange one of the light tones of a scale whose red will be brown.
253. In conformity with this manner of observing, when we would avoid the bad effect of two adjacent colours by white, black, or grey, we must see whether, instead of a harmony of contrast, it may not be better to obtain the harmony of analogy.
254. Finally, when we bring into combination not normal grey, but a coloured grey, we are always sure of obtaining an effective harmony of contrast by taking a grey coloured with a complementary of that opposed to it. Thus an orange-grey or carmelite-brown or maroon has a good effect with light blue.
FIRST DIVISION.—IMITATION OF COLOURED OBJECTS WITH COLOURED MATERIALS IN A STATE OF INFINITE DIVISION.
INTRODUCTION.
255. Coloured materials, such as Prussian blue, chrome-yellow, vermilion, &c., are infinitely divided, so to speak, either when ground pure, or mixed with a white material, in a gummy or oily liquid.
The reproduction of the images of coloured objects with these pigments is called the _Art of Painting_.
256. There are two systems of Painting—the one consists in representing as accurately as possible upon a flat surface an object in relief in such a way that the image makes an impression upon the eye of the spectator similar to that which the object itself would produce. This is termed the _Art of Chiaro-’scuro_.
257. There is a means of imitating coloured objects much simpler in its facility of execution than the preceding. It consists in tracing the outline of the different parts of the model, and in colouring them uniformly with their peculiar colours. There is no relief, no projection; it is the plane image of the object, since all the parts receive a uniform tint: this system of imitating is _Painting in Flat Tints_.
PAINTING ON THE SYSTEM OF CHIARO-’SCURO.
258. Are the modifications perceived in a single coloured object, for example, in a blue or red stuff, &c., indeterminable, when these draperies are seen as draperies of a vestment or furniture, with more or less distinct folds, or are they determinable, in given circumstances? This is a question of which I am about to attempt a solution.
259. Firstly, let us distinguish three circumstances in which modifications of colours may be observed:—
1. Modifications produced by coloured lights falling upon the model.
2. Modifications produced by two different lights—as, for example, the light of the sun and diffused daylight—each illuminating different parts of the same object.
3. Modifications produced by diffused daylight.
260. We will suppose that in the two first cases the lighted surfaces are plane, and that all their superficial parts are homogeneous, and in the same conditions, except that of light. In the third case, we shall consider the position of the spectator viewing an object lighted by diffused daylight, the surface of which is not so disposed as to act equally in all its parts upon the light which it reflects to the eye of the spectator.
261. Modifications produced by coloured lights.
Red rays falling on Black make it appear Purple-black. ” White ” Red. ” Red ” Redder. ” Orange ” Redder. ” Yellow ” Orange. ” Deep Green ” Red-black. ” Light Green ” Reddish-grey. ” Light Blue ” Violet. ” Violet ” Purple.
262. Modifications produced by Orange light.
Orange rays falling on— Black make it appear Maroon, or Carmelite-brown. White ” Orange. Orange ” More vivid. Red ” Scarlet. Yellow ” Yellow-orange. Light Green ” Yellow-green. Deep Green ” Rusty-green. Light Blue ” Orange-grey. Deep Blue ” Grey, slightly Orange-grey. Indigo Blue ” Orange-maroon. Violet ” Red-maroon.
263. Modifications produced by Yellow light.
Yellow rays falling on— Black make it appear Yellow-olive. White ” Light Yellow. Yellow ” Orange-yellow. Red ” Orange. Orange ” Yellower. Green ” Greenish-yellow. Light Blue ” Yellow-green. Deep Blue ” Green-slate. Indigo ” Orange-yellow. Violet ” Yellow-maroon.
264. Modifications produced by Green light.
Green rays falling on— Black make it appear Greenish-brown. White ” Green. Green ” More intense and brilliant. Red ” Brown. Orange ” Faint Yellow, a little Green. Green ” Greener, according to its depth. Indigo ” Dull Green. Violet ” Bluish-green Brown.
265. Modifications produced by Blue light.
Blue rays falling on Black make it appear Blue-black. Black ” White ” Blue. ” ” Blue ” More vivid. ” ” Red ” Violet. { Brown, having a ” ” Orange ” { pale tint of Violet. Blue ” Yellow ” Green. ” ” Green ” Blue-green. ” ” Indigo ” Dark-blue Indigo. ” ” Violet ” Dark-blue Violet.
266. Modifications produced by Violet light.
{Very faint Violet rays falling on Black make it appear {Violet-black. ” ” White ” Violet. ” ” Violet ” Deeper Violet. {Red-violet ” ” Red ” {Purple. ” ” Orange ” Light Red. {Brown, with a ” ” Yellow ” {very slight tint {of Red. ” ” Green ” Light Purple. {Fine Blue ” ” Blue ” {Violet. {Deep Blue ” ” Indigo ” {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 exposing 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.
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 daylight.
_An object lighted partly by the sun, and partly by diffused 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 I., fig 4) and place in the middle a piece of black wire _f, fʹ_; then put parallel to this, and in the middle between A and B, two wires _e, eʹ_ and _g, gʹ_, of about three-tenths of an inch in width. The extremity _gʹ_ is fixed upon a perpendicular plane, so high, that all the part B _f, fʹ_ may be in shadow.
272. 1. _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 _aʹ_, as the portion _b_ is bluer than the portion _bʹ_.
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 _aʹ_, as _b_ is more grey and duller than _bʹ_.
274. 3. _If the stuff is yellow_, A is more vivid, more orange than B; _a_ is more so than _aʹ_, as _b_ is duller than _bʹ_.
275. 4. _If the stuff is green_, A is less blue or more yellow than B; and _a_ is of a yellower green than _aʹ_, as _b_ is bluer than _bʹ_.
276. 5. _If the stuff is blue_, A is less violet and more green than B; and _a_ is greener than _aʹ_, as _b_ is more violet or less green than _bʹ_.
277. 6. _If the stuff is indigo_, A is redder or less blue than B; and _a_ is redder than _aʹ_, as _b_ is deeper or bluer than _bʹ_.
278. 7. If the stuff is violet, A is less blue than B; and _a_ is redder than _aʹ_ as _b_ is bluer than _bʹ_.
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 I., fig. 5) upon the partition _b_, of a chamber receiving diffused daylight by a window _f_: 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 positions 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 reflected by a surface all the parts of which are not in the same position relatively to the eye of the spectator._
281. Distant bodies are rendered perceptible to the eye only in proportion as they radiate or reflect, or 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 of 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 homogeneous 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.
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 perceive 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 imperceptible.
_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 uniformly 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 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 decided 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 less bright and of dark colours.
_Example 5._—There are some stuffs which appear to be of two tones of the same scale of colour, and sometimes also of two tones of two contiguous scales, although 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 direction 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 spectator, 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 simultaneous 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, contiguous 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 towards a window which admits daylight, and a person clothed in a new blue coat, dyed with indigo or Prussian blue, be at the window, the eye will see one part of the coat will appear different from the other part, because the nap of the cloth is disposed in a contrary direction; one being of a fine blue, while the other is of an orange-grey, by the effect of contrast 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 position by wear, the cloth becoming dull and soiled, the coloured light is reflected irregularly from all points; and the effect is either absolutely destroyed or 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 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, &c. (belonging to the same scale)—of a skein of silk or wool, placed upon an easel, that one-half of the same skein presents to the eye the threads disposed in a contrary direction to those of the other half. The half of the skein which does not reflect coloured light to the eye, appears tinted with the complementary of the other half which does reflect it.
290. Fourth modification in a stuff presenting a dark and a light tone belonging to the same scale.
If we place in juxtaposition a dark tone and a light tone of the same scale, well assorted, the light tone will appear of the colour complementary to the scale to which it belongs. This modification is too important to allow me to pass it over hastily.
291. When we look for several seconds on a fabric dyed with a coloured ground, and on which therefore patterns intended to be white, but which, owing to the imperfection of the process employed, have received a light tone of the colour of the ground, the patterns will appear of the colour complementary to the latter. Thus, upon a ground of yellow-chromate of lead, they will appear violet; upon a ground of orange-chrome, they will appear blue; upon a green ground, rose, &c. To dispel the illusion, and to recognise the true tint of the pattern, it is only necessary to cover the ground with a white paper so perforated as to leave visible only the pattern coloured like the ground. The influence of a dark tone upon a feeble tone is such, that not only is the latter neutralized, but the place it occupies upon the cloth appears also tinted with its complementary colour.
292. From the preceding observations it follows that there may be a printed cotton, the design of which, although coloured, will appear to most eyes white, and not of the complementary of the ground. For those eyes which see it thus, the perception of the phenomenon of contrast will correct the imperfection of the art of the calico-printer.
293. In the Lectures upon Contrast, which I delivered in 1836, at the Gobelins, I remarked, that in applying paper (cut for the purpose) upon the lights of a blue drapery of the Virgin in a tapestry representing the Holy Family, after Raphael, they appeared of a light blue, although, when they were seen surrounded with darker tones, they appeared of an orange tint.
294. We can conceive without difficulty that if the modification is not manifested with monochromous objects of vivid colours, as yellow, scarlet, &c., it is because that part of the surface of these objects which reflects the least light to the eye, always reflects enough of its peculiar colour to neutralize the complementary which the coloured light of the illuminated portion tends to develop. I believe that this effect tends to enfeeble the coloured light of the shaded part.
295. Although, in this chapter, I do not propose to treat of the modifications shown by coloured stuffs with white designs; yet, as it is a case so connected with the preceding considerations, I cannot avoid mentioning them in this place.
296. If we observe a sky-blue silk with white flowers, the weft of which is in an opposite direction to the weft of the blue ground, we shall see the flowers white, if they are placed in the most favourable manner to receive the white light reflected by them; while, in the contrary position, we shall see these flowers absolutely orange. There is still much white light reflected, but it is not sufficiently vivid to neutralize the development of the complementary of the ground.
PAINTING ON THE SYSTEM OF FLAT TINTS.
297. In painting by flat tints, the colours are neither shaded, blended together, nor modified by the coloured rays coming from the surrounding parts of the picture.
In pictures which belong to this kind of painting, the representation of the model is reduced to the observance of linear perspective, to the employment of vivid colours in the nearer parts, and of pale and grey colours in the more distant.
If the choice of contiguous colours has been made conformably to the law of simultaneous contrast, the effect of the colour will be greater than if it had been painted on the system of chiaro-’scuro.
298. In every instance where painting is an accessory, and not a principal feature, painting in flat tints is in every respect preferable to the other kind.
299. The essential qualities of painting in flat tints necessarily reside in the good choice of colours and well drawn outlines. These outlines contribute to render the impressions of colours stronger and more agreeable, when, circumscribing forms clothed in colours, they concur with them in suggesting to the mind a graceful object, when even the imitation of it does not give a faithful representation.
300. We may, in conformity with what has been said, consider that painting in flat tints may be advantageously employed,
1. When the objects represented are at such a distance that the finish of an elaborate picture would disappear.
2. When a picture is an accessory, decorating an object whose use would forbid too elaborate finish, and which would also be too costly. Such are the paintings which ornament screens, work-boxes, tables, &c.; in this case the objects preferable as models, are those whose beauty of colours and simplicity of form are so remarkable as to attract the eye by simplicity of outline, and by vivid colours: such are birds, insects, flowers, &c.
SECTION III.
ON COLOURING IN PAINTING.