The fugitive colours do less injury in the shadows than in the lights of a picture, because they are employed purer and in greater body in the shadows, and are, therefore, less liable to decay by the action of light and by mixture; and, by partially fading, they balance any tendency to darken, to which the dead colouring of earthy and metallic pigments is disposed.

The foregoing circumstances, added to the variableness of pigments by nature, preparation, and sophistication, have often rendered their effects equivocal, and their powers questionable; all which considerations enforce the expediency of using colours as pure and free from unnecessary mixture as possible; for simplicity of composition and management is equally a maxim of good mechanism, good chemistry, and good colouring. Accordingly, in the latter respect, Sir Joshua Reynolds gives it as a maxim, that the less pigments are mixed, the brighter they appear; the causes of which we have mentioned already. His words are: "Two colours mixed together will not preserve the brightness of either of them single, nor will three be as bright as two: of this observation, simple as it is, an artist who wishes to colour bright will know the value." - Note xxxvii. to Dufresnoy's " Art of Painting."

There prevail, notwithstanding, two principles of practice on the palette, opposed to each other - the one, simple; the other, multiple. That of simplicity consists in employing as few pigments, etc. as possible; according to the extreme of which principle the three primary colours are sufficient for every purpose of the art. This is the principle of composition in colouring, the opposite of which may be called the principle of aggregation, and is in its extreme that of having as many pigments, if possible, as there are hues and shades of colour.

On the first plan every tint requires to be compounded; on the latter, one pigment supplies the place of several, which would be requisite in the first case to compose a tint; and as the more pigments and colours are compounded, the more they are deteriorated or defiled in colour, attenuated, and chemically set at variance, while original pigments are in general purer in colour as well as more dense and durable than compound tints, there appear to be sufficient reasons for both these modes of practice; whence it may fairly be inferred, that a practice composed of both will be best, and that the artist who aims at just and permanent effects should neither compound his pigments to the dilution and injury of their colours, when he can obtain pure intermediate tints in single, permanent, original pigments, nor yet multiply his pigments unnecessarily with such as are of hues and tints he can safely compose extemporaneously of original colours upon his palette. This will require experience; and to facilitate the acquisition of such experience is one of the objects of this work.

Examples are to be found of each of these modes in the practice of the most eminent artists; and if the records left us of their palettes prove the fact, the mode of Rubens, Teniers, Hogarth, and Wilson, was more or less that of simplicity. With respect to Sir Joshua Reynolds, we have been assured by his favourite pupil, the venerable Northcote, who was every way interested in remarking and remembering his methods, that however he might have been betrayed by his materials, his practice in using them was regulated by that breadth, simplicity, and generality which marked his philosophic mind, and that hence he placed no expletive tints upon his palette, nor did he torture his colours with the palette-knife or pencil: by which judicious practice, his pictures, notwithstanding partial failures, have triumphed over the imperfection of his materials, and such of his works as have been preserved will remain to posterity with a permanence of hue not inferior to those of any of his great predecessors; while there is a grace and refinement in all his productions, that insure lasting esteem to those even of which the colouring may have partially flown, owing to the employment of the carmine of cochineal and orpiment with blue-black in the formation of his tints; which three, with black and white, constituted the ordinary setting of his palette, till he was forced very unwillingly to give up the two first for vermilion and Naples yellow, which he afterwards continued to employ as long as he painted. Ru-bens's advice to his pupils, preserved by the Chevalier Mechel, is that of the utmost simplicity; thus, in the painting of flesh, he says: "Paint your high lights white; place next to it yellow, then red, using dark red as it passes into shadow; then with a brush filled with cool grey, pass gently over the whole until they are tempered and sweetened to the tone you wish." To materialize this advice according to the improvements of the modern palette, take for the first colour flake-white or the best white lead; for the second, cool lemon or warm Naples yellow; for the third, cool or warm vermilion broken into shadow with madder carmine and manganese, or Cappagh, brown; and for the last, mineral grey, i. e. ultramarine ashes. With these, and with a horror of black even when painting a Negro, following the advice of Rubens and Reynolds, it will be an artist's own fault if he do not paint flesh that is at once natural, beautiful, and durable.

Vandyke's practice was similar to his master's; and such also was that of Correggio, who painted his flesh with the three primary colours, loaded or embossed his lights, and moderately softened them into his mezzotints, carefully preserving his shadows uncontaminated with white. There is indeed ever something in simplicity which associates it with grace, truth, beauty, and excellence: - " O Bister, meek of Truth, To my admiring youth Thy sober aid and native charms infuse I The flow'rs that sweetest breathe, Though beauty cull'd the wreath, Still ask thy hand to range their order'd hues." Collins: Ode to Simplicity. The practice of Sir Thomas Lawrence and the late Mr. Owen affords examples of the aggregate mode, which is well suited also to the painters of flowers and subjects of natural history; and many of the ablest living artists practise in the middle mode, which is certainly less dangerous in respect to permanence.