One point is the brightest in the eye as on the object; this is the point of light: from it in all directions the existent parts advance or recede, by, before, behind each other; the two extremes of light and shade make a whole, which the local or essential colour defines,--its coalition with the demi-tint, the shade and reflexes, rounds,--and the correspondence of each colour with all, tunes. The principles that regulate the choice of colours are in themselves as invariable as the light from which they spring, and as the shade that absorbs them. Their economy is neither arbitrary nor phantastic. Of this every one may convince himself who can contemplate a prism. Whatever the colours be, they follow each other in regular order; they emerge from, they flow into each other. No confusion can break or thwart their gradations, from blue to yellow, from yellow to red; the flame of every light, without a prisma, establishes this immutable scale. From this theory you will not expect that I should enter into chemic disquisitions on the materials, or into technic ones on the methods of painting. When you are told that _simplicity and keeping_ are the basis of purity and harmony, that _one_ colour has a greater power than a combination of two, that a mixture of three impairs that power still more, you are in possession of the great elemental principles necessary for the economy of your palette. Method, handling, and the modes of execution are taught by trial, comparison, and persevering practice, but chiefly by the nature, of the object you pursue. The lessons of repetition, disappointment, and blunder, impress more forcibly than the lessons of all masters. Not that I mean to depreciate or to level the comparative value or inferiority of materials, or that instruction which may shorten your road to the essential parts of study; but he is as far from Nature who sees her only through the medium of his master, as he from colour who fancies it lies in costly, scarce, or fine materials, in curious preparations, or mouldy secrets, in light, in dark, in smooth, in rough, or in absorbent grounds: it may be in all, but is in none of these. The masters of ancient colour had for their basis only four, and this simplicity made Reynolds conclude that they must have been as great in colour as in form. He who cannot make use of the worst must disgrace the best materials; and he whose palette is set or regulated by another's eye, renounces his own, and must become a mannerist. There is no compendious method of becoming great; the price of excellence is labour, and time that of immortality. Colour, like Design, has two essential parts, Imitation and Style. It begins in glare, is caught by deception, emerges to imitation, is finished by style, and debauched by manner.