an aptitude to see in succession green, you turn your gaze upon a yellow, you will receive an impression resulting from a mixture of green and yellow, the latter colour being modified by the phantom-supplementary of the red. These curious phenomena explain many facts remarked by dealers in coloured stuffs, and often greatly inconvenience artists who, wishing to imitate exactly the colours of their models, work at them so long at a time as to become partially insensible to the true tones. The experience of dealers in coloured stuffs shows, that when a purchaser has for some time looked at a yellow fabric, and is then shown orange or scarlet stuffs, he takes them to be amaranth-red or crimson; for his eye, excited by the yellow, has acquired an aptitude to see violet, and in consequence all the yellow of the scarlet or orange stuff disappears, and he sees red, or a red tinged with violet. A second fact connected with the phenomenon of "accidental colour" is, that if there be presented to a buyer, one after another, a dozen pieces of red stuff, he will consider the last five or six less beautiful than those first seen, although the pieces be identically the same. "What is the cause of this error of judgment? It is that the eyes having seen six or seven red pieces in succession, are in the same condition as if they had been looking fixedly for the same period at a single piece of red stuff; so that they have a tendency to see the complementary of Red-that is to say, Green. This tendency necessarily enfeebles the brilliancy of the red of the later-seen pieces [by dashing it with green]. And in order that the merchant may not suffer by the fatigue of his customer's eyes, he must take care, after having shown the latter six or seven pieces of red, to present to him some green pieces, in order to restore the eyes to their normal state. If the sight of the green be sufficiently prolonged to exceed the normal state, the eyes will acquire a tendency to see red-in which case the last six pieces will appear more beautiful than the others."*

The leading fact involved in those

singular phenomena is, that whenever the visual sense has been long acted upon by a certain colour, nature at once relieves and gratifies itself by calling up a spectral colour which is the harmonious opposite of the one beheld. And this either simultaneously (as a fringe round the object, if it be small, or by blending with and modifying its hue, if large)—or in succession, after the coloured object is removed. These spectral hues, to use the common phrase, have no existence in the outer world, they exist only upon the retina of the eye; and are the result of the physical constitution acting in accordance with the wants of the animating Spirit within. We have no doubt, however as the laws of Matter and of Mind are identical, and as the former always tends to produce what the latter naturally desires-that a similar phenomenon does exist in the outer world, although too feebly to be discernible; and that the efflux of a certain kind of rays (say red) always tends to produce complementary vibrations (say green) in the surrounding ether. We know that this is the case with regard to sound; for whenever any note is produced, the surrounding particles of metal or air always produce a series of complementary notes called the harmonics. Maupertuis long ago maintained that, after having listened to any note, the mind expects to hear one of the harmonics of that note. He was unquestionably right; and if he had said that the mind actually does, in certain cases, hear in imagination the expected note, and is all the more shocked when a wrong note comes, he would have been still more correct. In optics, as we have seen, this mental process is most apparent, -any given colour never failing to excite on the retina, and suggest to the mind, a colour which is the harmonious complementary of the one beheld. Thus, in Colour, we have the Law of Sympathy or Harmony made visible in its operation on the mind, while in Sound we have it made most perceptible in the outer world; but we entertain no doubt that its operation in both cases is at once physical and

metaphysical, influencing alike the nature without and the nature within.

That pressure upon the eye produces spectral colours, and that a sharp blow upon it makes us fancy we see a flash of light, is a fact known to everybody-but, like many another everyday phenomenon, its explanation has a good deal puzzled philosophers. Goethe attempted to explain it by the hypothesis that light resided in the eye, and came forth when thus strikingly appealed to; and Mr Field, taking fundamentally the same view, alleged that the eye secreted light, and thus gave it off. The real solution, as generally happens, is much simpler than the conjectured ones. All sense of light and colour, as we have said, is produced by ethereal vibrations upon the nerve of the eye; and the explanation of the above phenomenon is, that by pressure or concussion, the optic nerve is set a-vibrating, occasioning a sense of sight in the sensorium and mind. The brain is carefully protected by the hard covering of the skull, but if its particles happen to be set a-vibrating by a sharp dingling blow, the same sense of sight follows -as was recorded, for instance, in the case of the present Emperor of Austria, when violently struck with a poniard in the back part of the head by the Hungarian assassin at Vienna. In truth, all our sensations are produced by a vibratory motion in their respective nerves. The nerves peculiar to each organ, indeed, are susceptible of only one class of impressions-those of the eye, light and colours; those of the ear, sounds; those of the palate and nose, taste and smell. But this is simply owing to the fact that each requires a peculiar kind of matter to set it a-vibrat

ing; and if any one substance sufficed to set all of these various sets of nerves a-vibrating, it would at once produce all their varied phenomena. There is one substance, but one only, which has this power-namely, electricity; and its action, as is well known, actually does produce in all the organs of sense sensations peculiar to each in the eye, a flash of light; in the ear, sounds; in the nose, an odour; in the palate, a taste; in the skin, a pricking feeling—all in the same person and at the same moment of time.

Several attempts have of late years been made to construct a true science of colour-an important task, which has been long impeded by the unfortunate prevalence of the false theory of Beauty of which Lord Jeffrey was the cleverest expounder. The most successful of those inquirers into the nature of colour are Mr D. R. Hay, the appearance of whose Laws of Harmonious Colouring more than a quarter of a century ago, first gained public attention to this subject, and who has continued to develop his views in later and more costly works—and M. Chevreul, Member of the Institute of France, who has recently directed his able and pains-taking mind to this subject. This latter gentleman, who is favourably known for his discoveries in chemical science, was induced to devote his attention to Colour in consequence of his being appointed by his Government to superintend the dyeing department of the royal manufactories at the Gobelins. His work, accordingly, is purely scientific in its character, and by no means inviting to the general reader; but it contains a great deal of most valuable matter for those who are employed in work which requires taste in colouring.*

M. Chevreul's book, in fact, is an account of his researches on what he calls the Simultaneous Contrast of Colours. In his preface he says:"In endeavouring to discover the cause of the complaints made of the quality of certain pigments prepared in the dyeing laboratory of the Gobelins, I soon satisfied myself that if the complaints of the want of permanence in the light blues, violets, greys, and browns, were well founded, there were others-particularly those of the want of vigour in the blacks employed in making shades in blue and violet draperies-which had no foundation; for, after procuring blackdyed wools from the most celebrated French and other workshops, and perceiving that they had no superiority over those dyed at the Gobelins, I saw that the want of vigour complained of in the blacks was owing to the colour next to them, and was due to the phenomena of the contrast of colours." What, then, is this law of simultaneous contrast of colours? It is, that when we regard attentively two coloured objects at the same time, neither of them appears of the colour proper to it (that is to say, such as it would appear if viewed separately), but of a tint resulting from the proper colour and the complementary of the colour of the other object; and that, if the colours of the juxtaposed objects are not of the same tone, the lightest tone will be lowered, and the darkest tone will be heightened.

To explain. We know, from the phenomena of the spectral or "accidental" colours described above, that a red spot tends to diffuse over the surrounding space its complementary colour, green

That Green tends to diffuse Red

incline to orange, and the blue to green. If we take Yellow and Blue, the former will incline to orange, and the latter to violet. The fundamental reason of this phenomenon is, that each colour tends to diffuse its complementary hue over the colour or colours placed next to it. But this tendency is intensified by the physiological fact, that if any of our senses receives a double impression, one of which is vivid and strong but the other feeble, we do not perceive the latter; and that this is particularly the case when they are both of the same kind. For instance, if two knocks are given simultaneously at the opposite ends of a room, one very loud and the other weak, we only hear the strong one. Now, when red and blue are presented to the eye, the strength of the blue renders us insensible to any tinge of that colour which may be in the red, making the red yellower; and so with other colours. Nevertheless, the influence of this law in modifying juxtaposed colours must, we think, be little more than theoretical when compared with the far stronger influence exercised in this matter by the law of complementary colouring.

Let us give a few more examples of the changes produced by the contrast of colours :

Red and White.-Green, the complementary of Red, is added to the White. The Red appears more brilliant and deeper.

Orange and White.-Blue, the complementary of Orange, is added to the White. The Orange appears brighter and deeper.

Green and White.-Red, the complementary of Green, is added to the White. The Green appears brighter and deeper.

Blue and White.-Orange, the complementary of Blue, is added to the White. The Blue appears brighter and deeper.

Take the same colours in juxtaposition with black:

Red and Black.-Green, uniting with the Black, causes it to appear less reddish. The Red appears lighter or less brown, more oranged.

Orange and Black.-Blue, uniting with the Black, the latter appears less rusty, or bluer. The Orange appears brighter and yellower, or less brown.

Green and Black.-Red, uniting with the Black, the latter appears more violet

1. Take Red, and place it in contact with orange-red, and the former will appear purple, and the latter become more yellow. But if we put the Red in contact with a purple-red, the latter will appear bluer, and the former yellower or orange. So that the same Red will appear purple in the one case, and orange in the other.

2. Take Yellow, and place it beside an orange-yellow, the former will appear greenish, and the latter redder. But if we put the Yellow in contact with a greenish-yellow, the latter will appear greener, and the former more orange. So that the same Yellow will incline to green in the one case, and to orange in

the other.

3. Take Blue, and put it in contact with a greenish-blue, the first will incline to violet, and the second will appear yellower. But put the Blue beside a violet-blue, and the former will incline to green, and the latter will appear redder. So that the same Blue will in one case appear violet, and in the other greenish. "Thus we perceive," says M. Chevreul, "that the colours which painters term simple or primary-namely, Red, Yellow, and Blue-pass insensibly, by virtue of their juxtaposition, to the state of secondary or compound colours. For the same Red becomes either purple or orange according to the colour placed beside it, the same Yellow becomes either orange or green, and the same Blue either green or violet."

Ignorance of this law of contrast has given rise to many a dispute between drapers and manufacturers. M. Chevreul had several instances of this in his own experience. Certain drapers, he tells us, having given to a calicoprinter some cloths of a single colour -red, violet, and blue-upon which they wished black figures to be printed, complained that upon the red cloths he had put green patterns, upon the violet cloths greenish-yellow ones, and upon the blue orange-brown or copper-coloured ones, instead of the black figures which had been ordered. To convince them that they had no

ground for complaint, M. Chevreul took the cloths, and surrounded the patterns in such a way as to conceal the ground; upon which the designs appeared as black as could be desired. And still further to convince the malcontent drapers, he placed some cuttings of black cloth upon stuffs coloured red, violet, and blue; whereupon the cuttings appeared of the same hue as the printed designs-i. e., of the colour complementary to the ground; although the same cuttings, when placed upon a white ground, were of a beautiful black. In the models of tapestries for furniture we often err in the same way as these drapers did-namely, by neglecting to preserve a contrast between the ground and the dominant colour of the subjects placed upon it. For instance, if it is a crimson ground, ornamented with a wreath of flowers, the greater part of the flowers ought to be blue, yellow, and white. If we place red flowers upon such a ground, they will tend to become orange rather than purple, and ought to have a fringe of green leaves contiguous to the ground. On the contrary, when the ground is of a greenish hue, red and rose-coloured flowers must predominate over the others; and when the ground is of the hue of dead leaves, the blue, violet, white, and rose flowers detach themselves completely.

It is important that painters should understand this Law of Contrast in colouring. Suppose, for instance, a painter have to imitate two contiguous stripes of red and blue upon a white ground. He perceives them changed in hue, by the mutual effect of each upon the other, the red becoming more and more orange as it approaches the blue, and the latter more and more green as it approaches the red; but if he understands the law of contrast, he will know at once how to treat the illusion, and will produce the true effect by making his stripes respectively of a simple blue and a simple red, reduced in some parts by light or by shade. Whereas, if he does not understand the secret of the illusion, he will proceed to paint the stripes of a greenish-blue and yellowish-red, and so produce a false and exaggerated effect, from not knowing that the greenish and yellowish hues

of the stripes are merely the result of red and blue coming together, and that they will reproduce themselves on his canvass if he makes the one stripe simple red and the other simple blue.

Another point which it is most important that artists should bear in mind is, that if, after working long at one part of a picture, they turn their eyes to another part, that other part will not appear of its own colour, but of a hue resulting from a blending of the complementary colour of the first part of the picture with the actual colour of the second. For instance, if they have been painting a lady's red mantle, and then turn to look at the face, the complexion will appear of a greenish hue, which if the artist ignorantly reproduce on his canvass, he will most grievously sin against the truth, and deservedly earn the grievous displeasure of his fair sitter. In truth, so important is it to thoroughly understand the action of the "accidental colours," that it is a fact that even artists who are gifted with a fine eye for colour will produce poor effects if they make their sittings too long at a time. An ignorance of this law, and a habit of long sittings (things which generally go together, for no one who understands the former will indulge in the latter), will produce even with naturally fine colourists a colouring dull and inferior to that of artists who, though less finely organised, give way more to first impressions; or in other words, who take in the impression of the model more rapidly, before their eye has had time to become fatigued, and who do not too frequently return to their work to modify it, to efface, and to repaint, a process which infallibly produces a poor effect, and makes the Colouring "muddled." It is good for artists, then, as well as for other men, to know to "let well alone;" and by some members of the profession we know, the maxim is much needed.

We do not generally make a sufficient use of colour as a beautifier of our dwellings. This is partly owing to the fact that the physical organisation of northern nations is not so susceptible to the impressions of colour as is that of southern nations, even though these latter be intellectually our inferiors. It is in tropical countries, where light is most dazzling, that co

lour is most gorgeous and abundant. These are the native climes of the sapphire, the diamond, and the emerald,-of sunsets unspeakably gorgeous, and of night-skies through the azure of whose transparent depths the eye wanders upwards until it loses itself as if on the threshold of other worlds. The savannahs there are covered with perennial flowers; the pillared forests are linked in a maze of beauty by the scarlet and other brilliant blossoms of the trailers that hang in festoons from tree to tree; and the green mantle of earth flashes everywhere into colours beneath the flood of sunshine which keeps all nature a-pulsing to the rhythm of its subtle and inconceivably rapid vibrations. Colour, like its parent light, dies away towards the Poles; and as the constitution of nations is ever in harmony with the region where they dwell, the susceptibility of us hyperboreans to colour is far inferior to that of the race who produce the magic dyes of India, or the still nobler one who built the glowing walls of the Alhambra. Even our next-door neighbours the French beat us hollow in the art and use of colour; and we do not think we overstate the case when we say, that there is no civilised people on the earth who do not equal or excel us in a taste and passion for colour.

We are too fond of paleness, colourlessness, in our interiors. We shrink from bright colours, because we do not know how to use them, and believe we show taste when we have produced an effect which is simply commonplace. With M. Chevreul for our guide, let us offer a word or two upon this subject. We shall begin with the more grand and artistic parts of a mansion, and then come quickly down to remarks which may be as interesting to the single gentleman with his triplet of rooms in the Temple, as to the more stately occupants of palatial edifices. Enter a gallery of sculpture, and see what hints about colour there suggest themselves. Here we have our old friend the Venus de Medici - showing the perfection of physical beauty, but with as little as possible of the divine either in her head or attitude. Next to her, in not uncongenial contiguity, is Dan