Yellow light

“ Yellow is of the nature of simple light; blue, connected with simple shade; but red is an entirely abstract color. It is red to which the color-blind are blind, as if to show us that it was not necessary merely for the service or comfort of man, but that there was a special gift or teaching in this color. Observe, farther, that it is this color which the sunbeams take in 318 passing through the earth’s atmosphere. The rose of dawn and sunset is the hue of the rays passing close over the earth. It is also concentrated in the blood of man. ”

“ As I said before, the eye becomes dulled with regard to the yellow light, and thus sees Nature again in its normal coloring. The small quantity of blue light which is excluded by the yellow glass produces no sensible difference, as the difference is equalized by a diminution of sensibility with regard to yellow. ”

“ In the autumn, nearly all leaves show brilliant patches of colour.
In borrowing Nature’s colours to set forth our ideas, we have become possessors of a mighty vehicle of expression. With yellow, we can speak of life, light, cheer and vitality. Red tells of fire, heat, blood, excitement and passion. Blue indicates coolness, quiet and restraint. In choosing green for its most universal colour, Nature harmonizes life and restraint, warmth and coolness, as represented by the component blue and yellow. ”

“ Yellow being the colour of the sun and of corn and gold, represents riches, generosity, and light. Red stands between the dark and the lively colours, and represents warmth and animation, dignity, splendour, life, love, and joy. ”

“ When daylight struggles with candle- or lamp-light, one may notice that upon the white cloth of a dinner-table the light is blue and the shadows yellow or orange—the orange deepening as with the fading daylight the blue grows deeper, until the colour of the light and the shadow change places. The same principle may be noticed in firelight, but the redder the flame the greener will be the shadows. ”

“ Blue is existence. It is darkness seen through light; a contrasting of existence and nothingness. Yellow is relation. In yellow light we see the relation of objects in the clearest way. Red is feeling. When we see red, we are thrown back on our personal feelings.... ”

“ They discovered not only that in green the shadow is tinged with blue, but that blue is the direct result of the yellow-orange of light. Every one nowadays has noticed that, in looking fixedly at a green, it appears now bluish, now yellowish; just as in listening to an orchestra we can, by focusing our attention, hear predominantly the bass or the treble. So the Impressionists observed that in the most luminous colour there is a proportion of absorption, and that in the darkest shadow there exists some reflection. ”

“ We are familiar with the effects of red which are stimulating, exciting, or irritating. The toreador, recognizing this principle, waves a flaming red mantle before the bull. Blue has an exactly opposite effect. It quiets and soothes, and when it runs into violet, it becomes depressing. Experiment with purple lights and you will find that they give a note of gloom, mystery, or of impending disaster. Yellow is the color that brings gaiety and light-heartedness, as you will recall when you contrast your own feelings on a sunshiny day and on a gray day. ”

“ But the colour of light depends on its wave-length, precisely as the tone of sound depends on its wave-length. The waves producing red light are longer than those producing orange light, these are longer than the waves producing yellow light; and so the wave-lengths shorten down from yellow to green, thence to blue, to indigo, and finally to violet. Thus if a body shining86 in reality with a pure green colour, approached the observer with a velocity comparable with that of light, it would seem blue, indigo, or violet, according to the rate of approach ”

“ Whilst with increasing density of the air the blue of the sky brightens up and gradually passes over into white, the yellow of the sun gradually darkens and finally gives way to complete absence of light. ”

“ The kerchief about her shoulders over a light chemise rivals the rainbow. I try to fix my eyes on some predominating colour, but when I decide that it is yellow, in will blaze a green stronger than the yellow, and then huge red roses splash their lurid colour into the yellow and green, and royal purple and blue daisies and magenta buttercups career around in wild indifference as to conventional form and tint. ”

“ The combination of simple blue and yellow lights of suitable relative luminosities results in the formation of white or neutral light. If the blue is a little in excess, the combined light will be of a bluish tint; if the yellow is in excess, the combination will have a yellowish tint. It will never contain any trace of green. The combination of simple spectral blue and yellow is easily effected by the colour-patch apparatus, and the result will be found to bear out what has been said. ”

“ In lighting it is important to recognize the tendency of color toward neutrality. For example, a warm yellow light soon disappears as a hue and only its subtle influence is left; however, a yellow vase still appears yellow because it is contrasted with objects of other colors. In the case of colored light the light falls upon everything visible, and if there is no other light-source of another color with which to contrast it, its color appears gradually to fade. ”

“ This also explains the circumstance that a landscape, illuminated by bright white clouds, appears more yellow in general hue than when the clouds are not bright, though still retain-in their whiteness, the strong white light stimulating more powerfully the sets of nerves concerned in the production of yellow. ”

“ It is noticeable, however, that the white light resulting from the combination of blue and yellow, though it cannot be distinguished by the eye from ordinary white light, is yet possessed of very different properties. Most coloured objects when illuminated by it have their hues greatly altered; a piece of ribbon, for example, which in common light is bright red, will appear when held in the blue-yellow light to be of a dark slate colour, almost black. ”

“ The undulations which produce the phenomenon of blue light are supposed to be smaller and more rapid than those which give rise to the phenomenon of yellow light. The undulations from which yellow light results, are again quicker and more limited in their range of motion than those from which red light results; while those which give rise to heat are less frequent, and traverse a wider space than do any of the undulations on which the colored rays depend. ”

“ All kinds of artificial light impart some of their yellow to all colours, and while this kind of illumination improves the brilliancy of yellow and yellowish-reds, or of such colours as lie closely to yellow in the chromatic circle, it dulls and saddens blues, bluish-greens, and violet-blues, or in other words, the colours that are more distantly removed from the orange-yellow in the chromatic circle. ”

“ Helmholtz has revealed the cause of the green produced by a mixture of blue and yellow pigments. No natural colour is pure. A blue liquid, or a blue powder, permits not only the blue to pass through it, but a portion of the adjacent green. A yellow powder is transparent not only to the yellow light, but also in part to the adjacent green. Now, when blue and yellow are mixed together, the blue cuts off the yellow, the orange, and the red; the yellow, on the other hand, cuts off the violet, the indigo, and the blue. ”

“ Its colors, then, come from the play of sun-light among the yellow and violet substances distributed very curiously under its wrinkled skin. It passes from orange to yellow, from green to blue, through a series of wavering and rainbow-like shades, determined by the state of the light's radiation. Darkness blanches it, twilight gives it the most delicate marbled tints, the sun turns it dark. A part of the skin bruised or rubbed remains black, without growing white in the dark. ”

“ You know people are always calling yellow things golden, even when they are not at all the colour of gold, which, even unalloyed, is not a bright yellow. That shows that delightful yellows are not very positive, and that, as aforesaid, they need gleaming materials to help them. The light bright yellows, like jonquil and primrose, are scarcely usable in art, save in silk, whose gleam takes colour from and adds light to the local tint, just as sunlight does to the yellow blossoms which are so common in Nature. ”

“ The reason the sun has always looked yellow is that you could never see that blue portion of its spectrum. Remember, a thing gets bluer and bluer as it gets hotter. First we have red hot, bright red, yellow, white, then the electric arc is so hot that it gives blue light. ”

“ Thus the yellow spectrum of the setting sun thrown on the luminous sky, becomes blue, and changes with the colour or brightness of the clouds on which it appears. The red part of light being capable of struggling through thick and resisting mediums which intercept all other colours—is likewise the cause why the sun appears red when seen through a fog,—why distant light, though transmitted through blue or green glass, appears red—why lamps at a distance, seen through the smoke of a long street, are red, while those that are near, are white. ”

“ From the light being tinged with yellow, the half-tone partakes of the same warmth, which gives a greenish tint even to his grey tones. This conduct conveys an emanation of the principal light passing over the more delicate shadows. ”

“ For example, if one looks at the blue sky, notably at noon-time, on the side away from the sun, or at the morning or evening sky, shining yellow and red, one quickly becomes conscious of how our eyes take hold of the particular contribution which Light and Dark make to one or other of the two colour appearances. ”

“ The pale tints of electric lights, which make every face in a room look ghastly, will affect quite as disastrously every soft color in the furnishings. In ordinary gaslight a pair of white gloves looks yellow, and we have seen Welsbach lamps which threw out a violet-blue illumination, depressing in the extreme. Under a yellow glow, blues, greens, violets and purples are greatly changed. Under a violet glow, yellows and greens are ruined. To see all colors in about the same value that they possess by daylight one must have a light in which no color tone is apparent. ”

“ But without light there can be no colour, for there is no material, so to speak, from which to manufacture it. White light, as we have said before, is made up of red, blue, and yellow, and it is by the absorption of one or all of these that all tints are formed. The surface of a poppy leaf has the power of absorbing all the blue and a little of the yellow, reflecting the whole of the red and the remainder of the yellow, the mixture of the two forming scarlet. ”

“ Firstly then you notice, when a fragment of sodium is placed in a platinum spoon and introduced into a Bunsen's flame, an intensely yellow light is produced. It corresponds in refrangibility with the yellow band of the spectrum. Like our tuning-fork, it emits waves of a special period. When the white light from the electric lamp is sent through that flame, you will have ocular proof that the yellow flame intercepts the yellow of the spectrum ”

“ It is now, therefore, universally acknowledged, that the light of the sun, which to us seems perfectly homogeneal and white, is composed of no fewer than seven different colours, namely Red, Orange, Yellow, Green, Blue, Indigo and Violet. A body which appears of a red colour has the property of reflecting the red rays more powerfully than any of the others; a body of a green colour reflects the green rays more copiously than rays of any other colour, and so of the orange, yellow, blue, purple and violet. ”

“ That radiant energy which is wholly of a wave-length of maximum visibility, or, in other words, excites the sensation of yellow-green, is the most efficient in producing luminous sensation. Of course, no illuminants are available which approach this theoretical ideal and it is not likely that this would be a practical ideal. Under monochromatic yellow-green light the magical drapery of color would disappear and the surroundings would be a monochrome of shades of this hue. Having no colors with which to contrast this color, the world would be colorless. ”

“ A wave of a certain velocity and length gives us a certain sensation which we call blue; another awakens the sensation we call yellow. The two series of waves, mingling, produce a new sensation which we call green. The necessity of reflection for the production of these sensations is evident. The mingled waves have no color in their incident flow; but, striking some object, these waves become separated, some being absorbed, and the reflected ones produce the peculiar sensation we call color.
We know that these varying conditions of light which affect us as color have an absolute being. ”

“ Still more important are the changes of hue which coloured [Pg 51] surfaces, and even the pure colours of the spectrum, undergo under the influence of a brighter or dimmer light. As the luminous source is brought nearer, violet takes a bluish tinge, green tends to become a whitish yellow, and red a brilliant yellow. ”

“ By such means it is possible to imitate the phenomena of the firmament; we can produce its pure blue, and cause it to vary as in nature. The milkiness which steals over the heavens, and enables us to distinguish one cloudless day from another, can be produced with the greatest ease. The yellow, orange, and red light of the morning and evening can also be obtained: indeed the effects are so strikingly alike as to suggest a common origin—that the colours of the sky are due to minute particles diffused through the atmosphere. ”