this analogy ceases, if it be true, as philosophers have argued and poets sung, that—

"Nature,

The art of heav'n, the order of this frame,—

Is only Music in another name."

CATHARINE Phillips.

In furnishing or setting the palette philosophically, harmonically, and upon principle, according to the preceding relations, it is necessary to supply it with pure blue, red, and yellow;—to oppose to these an orange, of a hue that will neutralize the blue -green, of a hue that will neutralize the red — and purple, of a hue that will neutralize the yellow; and so and so on to black and white that also neutralize each other. As in nature, the general colour of the sky is blue, and the colour of light is always opposite to that of the sky and shade, the white which is to represent light should be tinged with the orange of the palette sufficiently to neutralize the predominant coldness of black; and pure neutral white may thus be reserved as a local colour, by which term is understood, technically, the natural colour of an object unvaried by distance, reflection, or any other circumstance interfering with distinct vision, although, properly speaking, local colours are subject to all the relations and effects of the places they occupy in a composition, whether of light,

shade, colour, reflection, or distance; and the term is sometimes understood in this latter sense, and upon this their management depends.

This principle of setting a palette requires that all the colours should be as much as possible in contrast and accordance; and a palette thus tuned or set will afford facilities and conduct to harmonious colouring in ways as various, under the eye of taste and judgment, as the melodies and harmonies which music can elicit, through the genius of the composer, from a fine-toned and well-tuned instrument. It is admitted, nevertheless, that an able hand, guided by fine sense and a judicious mind, may realize fine effects in either art with irregular and inferior means; and granting also that such setting of a palette is theoretical, it is nevertheless not a false refinement, since it is founded in nature, and assimilates with the most approved general practice, and the constant aim of the most eminent colourists; we offer it therefore only as consequent to the relations of which we have been treating.

Such observances may, notwithstanding, we repeat, be held unnecessary to the few in whom the perceptions of sense are so powerful, that, with little of the aid of intellect and less of science, they operate and produce with the grace and certainty of nature, as it were by instinct, compared with which the productions of science are mere mimickry. This is the inspiring principle called ge

nius, in which we recognise Divinity; to be fraught with which in perfection is to be above human rule, to mark an æra, and to give canons to art. But though indisposed with some to deny such principle altogether, we admit it to be, in perfection, of the rarest occurrence only, and hold that most excellences of human art have been the joint results of application and rule or science; -or, in other words, of true theory and assiduous practice combined. It has hence been objected that rules are but fetters to genius; and it may be remarked that they enable men of little ability to produce considerable works mechanically; and both these have some truth when rules are used without their reasons: but reason does not fetter genius; on the contrary, genius itself is latent reason operating by natural rules unconsciously.

The foregoing principle of contrast in colours is of so wide an application in practice, that there is scarcely a case of the employment of colours to which it is not of importance, and a treatise thereon might be swelled without limit; but the principle, which is sufficiently simple, and obvious to common attention, is of such easy application, that enlargement thereon is needless to the intelligent artist and manufacturer, nor can it easily escape his observation in the most delicate cases; as, for instance, in irredescent or dubious colours, which occur in the plumage of birds and in innumerable natural objects, and are imitated in

what are called shot-silks, &c., in all which they captivate vision by their beauty when duly contrasted and related as they always are in nature, although often disgustingly compounded in art when unresolved blues and greens, orange and yellow, &c. are associated, producing dissonance instead of that irredescence which arises from the natural chords and consonances of colours so analogous to the chords and cadences of the æolian lyre. These principles are especially applicable to the rendering unapparent or faint colours very apparent, by opposing to them strong contrasting colours, whereby the eye is rendered sufficiently sensitive to discern them.

CHAPTER IV.

ON THE PHYSICAL CAUSES OF COLOURS, &c.

"The mind of Leonardo was, however, too active and capacious to be contented solely with the practical part of his art; nor could it submit to receive as principles, conclusions, though confirmed by experience, without first tracing them to their source, and investigating their causes, and the several circumstances on which they depended."—Hawkins's Life of Da Vinci, p. 19.

In treating of pigments, there is no speculation more natural than the inquiry, What are the physical causes of colour in general? We shall not, therefore, pass it over unnoticed, more especially because the right explanation of many effects and appearances, both of colour and vision, in which the artist is concerned depend upon its solution, though it is a question of undoubted difficulty, which has never been satisfactorily answered; being perhaps too abstract and elementary to admit of sensible demonstration, and therefore incapable of popular solution. Hence the theory of colours has varied with the changes of philosophy, and the fashions of the mind.

According to common apprehension, colours are inherent or substantial qualities of bodies, or

F