be reduced to simpler terms: thus the equal proportionals 8, to both which the two ends of the needle or index point on the scale, are as unity, 1=1,— the simplest of all ratios, that of equality; and its colours are orange and blue,-literally the points of extreme hot and cold, which are, so to call them, the poles of harmony in colouring. This result is accidental, but it is a coincidence which evinces the truth of our process, and singularly comports with the rule of harmony in painting, which has been founded on sense or feeling, and requires that equality or balance of warm and cool colouring in a picture upon which tone so essentially depends.*

These are the only two contrasting colours which, like black and white, are equal powers: all other contrasts are perfect only when one of the antagonist colours predominates according to the proportions marked upon the scale. A line diagonally across the needle, or index, indicates the positions of the scale at which colours become most advancing and most retiring; and a like line perpendicularly across the scale points out all the middle colours. These three lines divide the entire scale into equal portions throughout.

Again, by the Scale of Chromatic Equivalents may be determined the proportions in which any three colours neutralize and harmonize each other: thus, as 3, 5, and 8, are these proportions of the primaries, yellow, red, and blue, so 8, 11, and 13, are those of the secondaries, orange, green, and purple. For the more readily finding the proportions of any three harmonizing colours on the scale, it is graduated all round, and divided into three equal parts, which are each subdivided into 32 degrees, numbered accordingly on the outward edge of the scale, and trisecting it all round, so that each colour of the scheme with its two harmonics are indicated by the same number, and the numbers corresponding on the inward edge show their proportions. In like manner may be found the proportions of six or nine harmonizing colours, &c. By causing this external circle of figures to move round the scale, it may be made to indicate the proportions of any number and variety of hues which harmonize; but this is unimportant for practice. This scheme is also a key to the whole science of nature in the painting of

* This balance and insensible union of hues and shades in painting, and of tones in music, the Greeks denominated by the same term, TONOS. "Tandem se ars ipsa distinxit, et invenit lumen atque umbras, differentia colorum alterna vice sese excitante: postea deinde adjectus est splendor, alius hic quam lumen; quem, quia inter hoc et umbram esset, appellaverunt róvov :" says PLINY, 1. xxxv. c. 5.

flowers, and it coincides therewith that the archetype of all floreal forms is triadic, consisting of the involution of triangles variously irradiated; the numbers of their rays or leaves being invariably 3, 4, or 5, or multiples thereof;―of which only by the by.*

By attention to these relations the student may approximate to a just conception of the powers of colours, and, assisted by of colours, and, assisted by a good eye, and a knowledge of his materials, may attain to a perfect application of them; by a like attention to these powers of colours the engraver too will be enabled to estimate those due additions of light or shade which may be necessary to compensate for the absence of colours in his performance; or, in other words, to represent them by their exact equivalents of light and shade.

It has been remarked as a common deficiency of young painters, that their figures, though well drawn, have wanted relief, and that the early works of Vandyke, Titian, and other great masters, have had the same deficiency; for the perfect management of light, shade, and colour, upon which relief depends, is ever of latest attainment, and some there are who never attain it. Yet others, unacquainted with the relations and powers of colours, and even wanting natural feeling therein, colour well by creating for themselves an artificial eye for colouring, and building on the taste and science of other masters, by constantly having a finely-coloured picture as a model while painting. This is nevertheless to be approved where science and nature are wanting, and has by persevering practice established both in the same person; for habit is art and second nature.

We may learn farther from these relations of colours, why dapplings of two or more colours produce effects in painting so much more clear and brilliant, than uniform tints produced by compounding the same colours ;why also, as justly remarked by Sir Joshua Reynolds, colours mixed deteriorate each other, which they do more by imperfectly neutralizing or subduing each other chromatically, than by any chemical action or discordance, though the latter is sometimes also to be taken into the account;-they impress too, on the good colourist, not only the necessity of using his colours pure, but that also of using pure colours; nevertheless, pure colouring and brilliancy differ as much from crudeness and harshness, as tone and harmony do from murkiness and monotony, though both these have been confounded by the injudicious.

* See farther, Exp. xxvIII. Chap. XXVI.

D

The power of colours in contrasting each other agrees with their correlative powers of light and shade, and is to be distinguished from their power individually on the eye, which is one of light alone: thus, although orange and blue are equal powers as respects each other, as respects the eye they are totally different and opposed; for orange is a luminous colour, and acts powerfully in irritating, while blue is a shadowy colour, and acts much less powerfully, or contrarily, in soothing that organ,-it is the same in various degrees with other colours; these powers resolve, therefore, ultimately into the same principles of light and shade in a sensible or latent

state.

There are yet other modes of contrast or antagonism in colouring, which claim the attention, and engage the skill of the colourist. That of which we have spoken is the contrast of hues, upon which depends the brilliancy, force, and harmony of colouring;-there is also the contrast of shades, to which belong all the powers of the chiar'-oscuro, which, though it is a part, and the simplest part of colouring only, and ought not to be separated from it, ranks as a distinct and is an important branch of painting, yet is the regimen of opposition in colours coincident with that of light and shade, or black and white; all that can be said of the latter may be said of the former, and he who excels in the one is in a considerable degree qualified to surpass in the other: indeed a just practice of light and shade might carry with it the reputation of good colouring, as it did in Rembrandt, while considerable knowledge of colouring, without the chiar'-oscuro, could not obtain the name of colourists for some eminent masters of the Italian schools. A third mode of contrast in colouring is that of warmth and coolness, upon which depends the toneing and general effect of a picture; besides which there is the contrast of colour and neutrality, the chromatic and achromatic, or of hue and shade, by the right management of which local colours acquire value, gradation, keeping, and connexion; whence comes breadth, aerial perspective, and the due distribution of grays and shadows in a picture.

This principle of contrast applies even to individual colours, and conduces greatly to good colouring, when it is carried into the variety of hue and tint in the same colour, not only as respects their light and shade, but also in regard to warmth and coolness, and likewise to colour and neutrality. Hence the judicious landscape-painter knows how to avail himself of warmth and coolness in the juxtaposition of his greens, as well as of their lightness

and darkness, or their brilliancy or brokenness, in producing the most beautiful and varied effects, which spring in other cases from a like management of blue, white, and other colours. These powers of a colour upon itself are highly important to the painter, and conduce to that gratification from fine colouring, by which a good eye is so mysteriously affected.

If we inspect the works of Nature closely, we shall find that they have no uniform tints, whether it be in the animal, vegetal, or mineral creation; -be it flesh or foliage, the earth or the sky, a flower or a stone, however uniform its colour may appear at a distance, it will when examined nearly, or even microscopically, be found constituted of a variety of hues and shades compounded with harmony and intelligence.

Transparency and opacity constitute another contrast of colouring, the first of which belongs to shade and blackness, the latter to light and whiteness;-even contrast has its contrast, for gradations, or intermedia, are antagonists to contrasts or extremes; and upon the right management of contrasts and gradation depends the harmony and melody, the breaks and cadences, the tone, effect, and expression of a picture; so that painting is an affair of judicious contrasting so far as it regards colour, if even it be not such altogether.

These contrasts may also be variously or totally conjoined; thus, in contrasting any colour, if we wish it to have light or brilliancy, we degrade, or cast its opposite into shade ;-if we would have it warm, we cool its antagonist;—and if transparent, we oppose it by an opaque contrary, and vice versa, &c. indeed, in practice, all these must be in some measure combined.

Such are some of the powers of contrast in colouring alone, and such the diversity of art upon which skill in colouring depends. It must not be forgotten, however, that contrasts or extremes, whether of light and shade, or of colours, become violent and offensive when they are not reconciled by the interposition of their media, or a mean which partakes of both extremes of a contrast; thus blue and orange in contrast become reconciled, softened in effect, and harmonized when a broken colour composed of the two is interposed; the same of other colours, shades, and contrasts.

Another important rule which belongs to the consideration of contrasts is, that that which holds of the one species, holds also of the others: hence the maxims of the chiar'-oscuro are applicable to contrasting colours; each have

their focus, should each mutually penetrate and diffuse,-be each repeated subordinately, that is, as principal and secondary, and mutually balance each other, &c. So much, indeed, is the management and mastery of colours dependent on the same principles as light and shade, that it might become a point of good discipline, for the perfect attainment thereof, after acquiring the use of black and white in the chiar'-oscuro, to paint designs in contrast; that is, with two contrasting colours only, in conjunction with black and white; for example, with blue and orange, previously to attempting the whole together. Black may even be dispensed with in these cases, because it may be compounded, since the neutral grey and third colours always arise from the compounding of contrasting colours, so that even flesh may be painted in this way; for example, with red and green alone, as Gainsborough is said to have done at one period of his practice. It is thus that one part of an art becomes a mirror to the rest.

By mixing his colours with white, the artist obtains what he has appropriately called his tints; by mixing colours with colours, he obtains compound colour or hues; finally, by mixing colours or tints with black, he gets what are properly called shades; yet these distinctions are very commonly confounded.

The foregoing classification of colours is an arrangement which exhibits a correct genealogy of their hues and shades in a general view, and enables us to comprehend the simplicity of relation which subsists among an infinity of hues, shades, and tints of colour, while it is calculated to give precision to language respecting colours, the nomenclature of which has ever been exceedingly arbitrary, mutable, and irrelative. The names of colours, consisting of terms imposed without general reference or analogy, according to views and fashions ever varying, are for the most part idiomatical and ambiguous in all languages; yet, boundless as is the variety of hues and compounds, the cultivated eye will readily distinguish the degrees of relation in every possible instance, to the preceding denominations of classes.

There are, however, some anomalous popular names of classes, which, being shades nearly allied to the tertiary colours, have been confounded. therewith, and being also of great practical importance merit the consideration of the colourist. These denominations comprehend all the combinations of the primary, secondary, and tertiary colours, with the neutral, black, or