The Tuning of Color cannot be left to Personal Whim. The wide discrepancies of red, yellow, and blue, which have been falsely taught as primary colors, can no more be tuned by a child than the musical novice can tune his instrument. Each of these hues has three variable factors (see page 14, paragraph 14), and scientific tests are necessary to measure and relate their uneven degrees of Hue, Value, and Chroma.

Visual estimates of color, without the help of any standard for comparison, are continually distorted by doubt, guess-work, and the fatigue of the eye. Hardly two persons can agree in the intelligible description of color. Not only do individuals differ, but the same eye will vary in its estimates from day to day. A frequent assumption that all strong pigments are equal in chroma, is far from the truth, and involves beginners in many mishaps. Thus the strongest blue-green, chromium sesquioxide, is but half the chroma of its red complement, the sulphuret of mercury. Yet ignorance is constantly leading to their unbalanced use. Indeed, some are still unaware that they are the complements of each other.[25]

[Footnote 25: See Appendix to Chapter III.]

It is evident that the fundamental scales of Hue, Value, and Chroma must be established by scientific measures, not by personal bias. This system is unique in the possession of such scales, made possible by the devising of special instruments for the measurement of color, and can therefore be trusted as a permanent basis for training the color sense.

The examples in Plates II. and III. show how successfully the tuned crayons, cards, and water colors of this system lead a child to fine appreciations of color harmony.

PLATE II.

COLOR STUDIES WITH TUNED CRAYONS IN THE LOWER GRADES.

Children have made every example on this plate, with no other material than the five crayons of middle hue, tempered with gray and black. A Color Sphere is always kept in the room for reference, and five color balls to match the five middle hues are placed in the hands of the youngest pupils. Starting with these middle points in the scales of Value and Chroma, they learn to estimate rightly all lighter and darker values, all weaker and stronger chromas, and gradually build up a disciplined judgment of color.

Each study can be made the basis of many variations by a simple change of one color element, as suggested in the text.

1. Butterfly. Yellow and black crayon. Vary by using any single crayon with black.

2. Dish. Red crayon, blue and green crayons for back and foreground. Vary by using the two opposites of any color chosen for the dish and omitting the two neighboring colors. See No. 4.

3. Hiawatha's canoe. Yellow crayon, with rim and name in green. Vary color of canoe, keeping the rim a neighboring color. See No. 4.

4. Color-circle. Gray crayon for centre, and five crayons spaced equidistant. This gives the invariable order, red, yellow, green, blue, purple. Never use all five in a single design. Either use a color and its two neighbors or a color and its two opposites. By mingling touches of any two neighbors, the intermediates are made and named yellow-red (orange), green-yellow, blue-green, purple-blue (violet), and red-purple. Abbreviated, the circle reads R, YR, Y, GY, G, BG, B, PB, P, RP.

5. Rosette. Red cross in centre, green leaves: blue field, black outline. Vary as in No. 2.

6. Rosette. Green centre and edge of leaves, purple field and black accents. Vary color of centre, keeping field two colors distant.

7. Plaid. Use any three crayons with black. Vary the trio.

8. Folding screen. Yellow field (lightly applied), green and black edge. Make lighter and darker values of each color, and arrange in scales graded from black to white.

9. Rug. Light red field with solid red centre, border pattern and edges of gray. This is called self-color. Change to each of the crayons.

10. Rug. Light yellow field and solid centre, with purple and black in border design. Vary by change of ground, keeping design two colors distant and darkened with black.

11. Lattice. Yellow with black: alternate green and blue lozenges. Vary by keeping the lozenges of two neighboring colors, but one color removed from that of the lattice.

For principles involved in these color groups, see Chapter III.

PLATE III.

COLOR STUDIES WITH TUNED WATER COLORS IN THE UPPER GRADES.

Previous work with measured scales, made by the tuned crayons and tested by reference to the color sphere, have so trained the color judgment that children may now be trusted with more flexible material. They have memorized the equable degrees of color on the equator of the sphere, and found how lighter colors may balance darker colors, how small areas of stronger chroma may be balanced by larger masses of weaker chroma, and in general gained a disciplined color sense. Definite impressions and clear thinking have taken the place of guess-work and blundering.

Thus, before reaching the secondary school, they are put in possession of the color faculty by a system and notation similar to that which was devised centuries ago for the musical sense. No system, however logical, will produce the artist, but every artist needs some systematic training at the outset, and this simple method by measured scales is believed to be the best yet devised.





Each example on this plate may be made the basis of many variants, by small changes in the color steps, as suggested in the text, and further elaborated in Chapter VI. Indeed, the studies reproduced on Plates II. and III. are but a handful among hundreds of pleasing results produced in a single school.[26]

1. Pattern. Purple and green: the two united and thinned with water will give the ground. Vary with any other color pair.

2. Pattern. Figure in middle red, with darker blue-green accent. Ground of middle yellow, grayed with slight addition of the red and green. Vary with purple in place of blue-green.

3. Japanese teapot. Middle red, with background of lighter yellow and foreground of grayed middle yellow.

4. Variant on No. 3. Middle yellow, with slight addition of green. Foreground the same, with more red, and background of middle gray.

5. Group. Background of yellow-red, lighter vase in yellow-green, and darker vase of green, with slight addition of black. Vary by inversion of the colors in ground and darker vase.

6. Wall decoration. Frieze pattern made of cat-tails and leaves,—the leaves of blue-green with black, tails of yellow-red with black, and ground of the two colors united and thinned with water. Wall of blue-green, slightly grayed by additions of the two colors in the frieze. Dado could be a match of the cat-tails slightly grayer. See Fig. 23, page 82.

7. Group. Foreground in purple-blue, grayed with black. Vase of purple-red, and background in lighter yellow-red, grayed.

For analysis of the groups and means of recording them, see Chapter III.

[Footnote 26: The Pope School, Somerville, Mass.]



CHAPTER V.

A PIGMENT COLOR SPHERE.[27]

How to make a color sphere with pigments.

(102) The preceding chapters have built up an ideal color solid, in which every sensation of color finds its place and is clearly named by its degree of hue, value, and chroma.



It has been shown that the neutral centre of the system is a balancing point for all colors, that a line through this centre finds opposite colors which balance and complement each other; and we are now ready to make a practical application, carrying out these ideal relations of color as far as pigments will permit in a color sphere[27] (Fig. 16).

[Footnote 27: Patented Jan. 9, 1900.]

(103) The materials are quite simple. First a colorless globe, mounted so as to spin freely on its axis. Then a measured scale of value, specially devised for this purpose, obtained by the daylight photometer.[28] Next a set of carefully chosen pigments, whose reasonable permanence has been tested by long use, and which are prepared so that they will not glisten when spread on the surface of the globe, but give a uniformly mat surface. A glass palette, palette knife, and some fine brushes complete the list.

[Footnote 28: See paragraph 65.]

(104) Here is a list of the paints arranged in pairs to represent the five sets of opposite hues described in Chapter III., paragraphs 61-63:—

Color Pairs. Pigments Used. Chemical Nature.

Red and Venetian red. Calcined native earth. Blue-green. Viridian and Cobalt. Chromium sesquioxide.

Yellow and Raw Sienna. Native earth. Purple-blue. Ultramarine. Artificial product.

Green and Emerald green. Arsenate of copper. Red-purple. Purple madder. Extract of the madder plant.

Blue and Cobalt. Oxide of cobalt with alumina. Yellow-red. Orange cadmium. Sulphide of cadmium.

Purple and Madder and cobalt. See each pigment above. Green-yellow. Emerald green See each pigment above. and Sienna.

(105) These paints have various degrees of hue, value, and chroma, but can be tempered by additions of the neutrals, zinc white and ivory black, until each is brought to a middle value and tested on the value scale. After each pair has been thus balanced, they are painted in their appropriate spaces on the globe, forming an equator of balanced hues.



(106) The method of proving this balance has already been suggested in Chapter IV., paragraph 93. It consists of an ingenious implement devised by Clerk-Maxwell, which gives us a result of mixing colors without the chemical risks of letting them come in contact, and also measures accurately the quantity of each which is used (Fig. 17).

(107) This is called a Maxwell disc, and is nothing more than a circle of firm cardboard, pierced with a central hole to fit the spindle of a rotary motor, and with a radial slit from rim to centre, so that another disc may be slid over the first to cover any desired fraction of its surface. Let us paint one of these discs with Venetian red and the other with viridian and cobalt, the first pair in the list of pigments to be used on the globe.

(108) Having dried these two discs, one is combined with the other on the motor shaft so that each color occupies half the circle. As soon as the motor starts, the two colors are no longer distinguished, and rapid rotation melts them so perfectly that the eye sees a new color, due to their mixture on the retina. This new color is a reddish gray, showing that the red is more chromatic than the blue-green. But by stopping the motor and sliding the green disc to cover more of the red one, there comes a point where rotation melts them into a perfectly neutral gray. No hint of either hue remains, and the pair is said to balance.

(109) Since this balance has been obtained by unequal areas of the two pigments, it must compensate for a lack of equal chroma in the hues (see paragraphs 76, 77); and, to measure this inequality, a slightly larger disc, with decimal divisions on its rim, is placed back of the two painted ones. If this scale shows the red as occupying 3-1/3 parts of the area, while blue-green occupies 6-2/3 parts, then the blue-green must be only half as chromatic as the red, since it takes twice as much to produce the balance.

(110) The red is then grayed (diminished in chroma by additions of a middle gray) until it can occupy half the circle, with blue-green on the remaining half, and still produce neutrality when mixed by rotation. Each disc now reads 5 on the decimal scale. Lest the graying of red should have disturbed its value, it is again tested on the photometric scale, and reads 4.7, showing it has been slightly darkened by the graying process. A little white is therefore added until its value is restored to 5.

(111) The two opposites are now completely balanced, for they are equal in value (5), equal in chroma (5), and have proved their equality as complements by uniting in equal areas to form a neutral mixture. It only remains to apply them in their proper position on the sphere.

(112) A band is traced around the equator, divided in ten equal spaces, and lettered R, YR, Y, GY, G, BG, B, PB, P, and RP (see Fig. 18). This balanced red and blue-green are applied with the brush to spaces marked R and BG, care being taken to fill, but not to overstep the bounds, and the color laid absolutely flat, that no unevenness of value or chroma may disturb the balance.

(113) The next pair, represented by Raw Sienna and Ultramarine, is similarly brought to middle value, balanced by equal areas on the Maxwell discs, and, when correct in each quality, is painted in the spaces Y and PB. Emerald Green and Purple Madder, which form the next pigment pair, are similarly tempered, proved, and applied, followed by the two remaining pairs, until the equator of the globe presents its ten equal steps of middle hues.

An equator of ten balanced hues.

(114) Now comes the total test of this circuit of balanced hues by rotation of the sphere. As it gains speed, the colors flash less and less, and finally melt into a middle gray of perfect neutrality. Had it failed to produce this gray and shown a tinge of any hue still persisting, we should say that the persistent hue was in excess, or, conversely, that its opposite hue was deficient in chroma, and failed to preserve its share in the balance.



(115) For instance, had rotation discovered the persistence of reddish gray, it would have proved the red too strong, or its opposite, blue-green, too weak, and we should have been forced to retrace our steps, applying a correction until neutrality was established by the rotation test.

(116) This is the practical demonstration of the assertion (Chapter I., paragraph 8) that a color has three dimensions which can be measured. Each of these ten middle hues has proved its right to a definite place on the color globe by its measurements of value and chroma. Being of equal chroma, all are equidistant from the neutral centre, and, being equal in value, all are equally removed from the poles. If the warm hues (red and yellow) or the cool hues (blue and green) were in excess, the rotation test of the sphere would fail to produce grayness, and so detect its lack of balance.[29]

[Footnote 29: Such a test would have exposed the excess of warm color in the schemes of Runge and Chevreul, as shown in the Appendix to this chapter.]

A chromatic tuning fork.

(117) The five principal steps in this color equator are made in permanent enamel and carefully safeguarded, so that, if the pigments painted on the globe should change or become soiled, it could be at once detected and set right. These five are middle red (so called because midway between white and black, as well as midway between our strongest red and the neutral centre), middle yellow, middle green, middle blue, and middle purple. They may be called the CHROMATIC TUNING FORK, for they serve to establish the pitch of colors, as the musical tuning fork preserves the pitch of sounds.

Completion of a pigment color sphere.

(118) When the chromatic tuning fork has thus been obtained, the completion of the globe is only a matter of patience, for the same method can be applied at any level in the scale of value, and a new circuit of balanced hues made to conform with its position between the poles of white and black.



(119) The surface above and below the equatorial band is set off by parallels to match the photometric scale, making nine bands or value zones in all, of which the equator is fifth, the black pole being 0 and the white pole 10.

(120) Ten meridians carry the equatorial hues across all these value zones and trace the gradation of each hue through a complete scale from black to white, marked by their values, as shown in paragraph 68. Thus the red scale is R1, R2, R3, R4, R5 (middle red), R6, R7, R8, and R9, and similarly with each of the other hues. When the circle of hues corresponding to each level has been applied and tested, the entire surface of the globe is spread with a logical system of color scales, and the eye gratified with regular sequences which move by measured steps in each direction.

(121) Each meridian traces a scale of value for the hue in which it lies. Each parallel traces a scale of hue for the value at whose level it is drawn. Any oblique path across these scales traces a regular sequence, each step combining change of hue with a change of value and chroma. The more this path approaches the vertical, the less are its changes of hue and the more its changes of value and chroma; while, the nearer it comes to the horizontal, the less are its changes of value and chroma, while the greater become its changes of hue. Of these two oblique paths the first may be called that of a Luminist, or painter like Rembrandt, whose canvases present great contrasts of light and shade, while the second is that of the Colorist, such as Titian, whose work shows great fulness of hues without the violent extremes of white and black.

Total balance of the sphere tested by rotation on any desired axis.

(122) Not only does the mount of the color sphere permit its rotation on the vertical axis (white-black), but it is so hung that it may be spun on the ends of any desired axis, as, for instance, that joining our first color pair, red and blue-green. With this pair as poles of rotation, a new equator is traced through all the values of purple on one side and of green-yellow on the other, which the rotation test melts in a perfect balance of middle gray, proving the correctness of these values. In the same way it may be hung and tested on successive axes, until the total balance of the entire spherical series is proved.

(123) But this color system does not cease with the colors spread on the surface of a globe.[30] The first illustration of an orange filled with color was chosen for the purpose of stimulating the imagination to follow a surface color inward to the neutral axis by regular decrease of chroma. A slice at any level of the solid, as at value 8 (Fig. 10), shows each hue of that level passing by even steps of increasing grayness to the neutral gray N8 of the axis. In the case of red at this level, it is easily described by the notation R 8/3, R 8/2, R 8/1, of which the initial and upper numerals do not change, but the lower numeral traces loss of chroma by 3, 2, and 1 to the neutral axis.

[Footnote 30: No color is excluded from this system, but the excess and inequalities of pigment chroma are traced in the Color Atlas.]

(124) And there are stronger chromas of red outside the surface, which can be written R 8/4, R 8/5, R 8/6, etc. Indeed, our color measurements discover such differences of chroma in the various pigments used, that the color tree referred to in paragraphs 34, 35, is necessary to bring before the eye their maximum chromas, most of which are well outside the spherical shell and at various levels of value. One way to describe the color sphere is to suggest that a color tree, the intervals between whose irregular branches are filled with appropriate color, can be placed in a turning lathe and turned down until the color maxima are removed, thus producing a color solid no larger than the chroma of its weakest pigment (Fig. 2).

Charts of the color solid.

(125) Thus it becomes evident that, while the color sphere is a valuable help to the child in conceiving color relations, in uniting the three scales of color measure, and in furnishing with its mount an excellent test of the theory of color balance, yet it is always restricted to the chroma of its weakest color, the surplus chromas of all other colors being thought of as enormous mountains built out at various levels to reach the maxima of our pigments.

(126) The complete color solid is, therefore, of irregular shape, with mountains and valleys, corresponding to the inequalities of pigments. To display these inequalities to the eye, we must prepare cross sections or charts of the solid, some horizontal, some vertical, and others oblique.

(127) Such a set of charts forms an atlas of the color solid, enabling one to see any color in its relation to all other colors, and name it by its degree of hue, value, and chroma. Fig. 20 is a horizontal chart of all colors which present middle value (5), and describes by an uneven contour the chroma of every hue at this level. The dotted fifth circle is the equator of the color sphere, whose principal hues, R 5/5. Y 5/5, G 5/5, B 5/5, and P 5/5, form the chromatic tuning fork, paragraph 117.



(128) In this single chart the eye readily distinguishes some three hundred different colors, each of which may be written by its hue, value, and chroma. And even the slightest variation of one of them can be defined. Thus, if the principal red were to fade slightly, so that it was a trifle lighter and a trifle weaker than the enamel, it would be written R{5.1/4.9}, showing it had lightened by 1 per cent. and weakened by 1 per cent. The discrimination made possible by this decimal notation is much finer than our present visual limit. Its use will stimulate finer perception of color.

(129) Such a very elementary sketch of the Color Solid and Color Atlas, which is all that can be given in the confines of this small book, will be elsewhere presented on a larger and more complete scale. It should be contrasted with the ideal form composed of prismatic colors, suggested in the last chapter, paragraphs 98, 99, which was shown to be impracticable, but whose ideal conditions it follows as far as the limitations of pigments permit.

(130) Besides its value in education as setting all our color notions in order, and supplying a simple method for their clear expression, it promises to do away with much of the misunderstanding that accompanies the every-day use of color.

(131) Popular color names are incongruous, irrational, and often ludicrous. One must smile in reading the list of 25 steps in a scale of blue, made by Schiffer-Muller in 1772:—

A. a. White pure. b. White silvery or pearly. c. White milky. B. a. Bluish white. b. Pearly white. c. Watery white. C. Blue being born. D. Blue dying or pale. E. Mignon blue. F. Celestial blue, or sky-color. G. a. Azure, or ultramarine. b. Complete or perfect blue. c. Fine or queen blue. H. Covert blue or turquoise. I. King blue (deep). J. Light brown blue or indigo. K. a. Persian blue or woad flower. b. Forge or steel blue. c. Livid blue. L. a. Blackish blue. b. Hellish blue. c. Black-blue. M. a. Blue-black or charcoal. b. Velvet black. c. Jet black.

The advantage of spacing these 25 colors in 13 groups, some with three and others with but one example, is not apparent; nor why ultramarine should be several steps above turquoise, for the reverse is generally true. Besides which the hue of turquoise is greenish, while that of ultramarine is purplish, but the list cannot show this; and the remarkable statement that one kind of blue is "hellish," while another is "celestial," should rest upon an experience that few can claim. Failing to define color-value and color-hue, the list gives no hint of color-strength, except at C and D, where one kind of blue is "dying" when the next is "being born," which not inaptly describes the color memory of many a person. Finally, it assures us that Queen blue is "fine" and King blue is "deep."

This year the fashionable shades are "burnt onion" and "fresh spinach." The florists talk of a "pink violet" and a "green pink." A maker of inks describes the red as a "true crimson scarlet," which is a contradiction in terms. These and a host of other names borrowed from the most heterogeneous sources, become outlawed as soon as the simple color terms and measures of this system are adopted.

Color anarchy is replaced by systematic color description.



APPENDIX TO CHAPTER V.

Color schemes based on Brewster's mistaken theory.



Runge, of Hamburg (1810), suggested that red, yellow, and blue be placed equidistant around the equator of a sphere, with white and black at opposite poles. As the yellow was very light and the blue very dark, any coherency in the value scales of red, yellow, and blue was impossible.

Chevreul, of Paris (1861), seeking uniform color scales for his workmen at the Gobelins, devised a hollow cylinder built up of ten color circles. The upper circle had red, yellow, and blue spaced equidistant, and, as in Runge's solid, yellow was very light and blue very dark. Each circle was then made "one-tenth" darker than the next above, until black was reached at the base. Although each circle was supposed to lie horizontally, only the black lowest circle presents a level of uniform values.

Yellow values increase their luminosity thrice as fast as purple values, so that each circle should tilt at an increasing angle, and the upper circle of strongest colors be inclined at 60deg. to the black base. Besides this fault shared with Runge's sphere, it falls into another by not diminishing the size of the lower circles where added black diminishes the chroma.

Desire to make colors fit a chosen contour, and the absence of measuring instruments, cause these schemes to ignore the facts of color relation. Like ancient maps made to satisfy a conqueror, they amuse by their distortion.

Brewster's mistaken theory underlies these schemes, as is also the case with Froebel's gifts, whose color balls continue to give wrong notions at the very threshold of color education. As pointed out in the Appendix to Chapter III., the "red-yellow-blue" theory inevitably spreads the warm field of yellow-red too far, and contracts the blue field, so that balance of color is rendered impossible, as illustrated in the gaudy chromo and flaming bill-board.

These schemes are criticised by Rood as "not only in the main arbitrary, but also vague"; and, although Chevreul's charts were published by the government in most elaborate form, their usefulness is small. Interest in the growth of the present system, because of its measured character, led Professor Rood to give assistance in the tests, and at his request a color sphere was made for the Physical Cabinet at Columbia.



CHAPTER VI.

COLOR NOTATION.

Suggestion of a chromatic score.



(132) The last chapter traced a series of steps leading to the construction of a practical color sphere. Each color was tested by appropriate instruments to assure its degree of hue, value, and chroma, before being placed in position. Then the total sphere was tested to detect any lack of balance.

(133) Each color was also written by a letter and two numerals, showing its place in the three scales of hue, value, and chroma. This naturally suggests, not only a record of each separate color sensation, but also a union of these records in series and groups to form a color score, similar to the musical score by which the measured relations of sound are recorded.

(134) A very simple form of color score may be easily imagined as a transparent envelope wrapped around the equator of the sphere, and forming a vertical cylinder (Fig. 21). On the envelope the equator traces a horizontal centre line, which is at 5 of the value scale, with zones 6, 7, 8, and 9 as parallels above, and the zones 4, 3, 2, and 1 below. Vertical lines are drawn through ten equidistant points on this centre line, corresponding with the divisions of the hue scale, and marked R, YR, Y, GY, G, BG, B, PB, P, and RP.

(135) The transparent envelope is thus divided into one hundred compartments, which provide for ten steps of value in each of the ten middle colors. Now, if we cut open this envelope along one of the verticals,—as, for instance, red-purple (RP), it may be spread out, making a flat chart of the color sphere (Fig. 22).

Why green is given the centre of the score.

(136) A cylindrical envelope might be opened on any desired meridian, but it is an advantage to have green (G) at the centre of the chart, and it is therefore opened at the opposite point, red-purple (RP). To the right of the green centre are the meridians of green-yellow (GY), yellow (Y), yellow-red (YR), and red (R), all of which are known as warm colors, because they contain yellow and red. To the left are the meridians of blue-green (BG), blue (B), purple-blue (PB), and purple (P), all of which are called cool colors, because they contain blue. Green, being neither warm nor cold of itself, and becoming so only by additions of yellow or of blue, thus serves as a balancing point or centre in the hue-scale.[31]

[Footnote 31: To put this in terms of the spectrum wave lengths, long waves at the red end of the spectrum give the sensation of warmth, while short waves at the violet end cause the sensation of coolness. Midway between these extremes is the wave length of green.]



(137) The color score presents four large divisions or color fields made by the intersection of the equator with the meridian of green. Above the centre are all light colors, and below it are all dark colors. To the right of the centre are all warm colors, and to the left are all cool colors. Middle green (5G 5/5) is the centre of balance for these contrasted qualities, recognized by all practical color workers. The chart forms a rectangle whose length equals the equator of the color sphere and its height equals the axis (a proportion of 3.14:1), representing a union and balance of the scales of hue and of value. This provides for two color dimensions; but, to be complete, the chart must provide for the third dimension, chroma.

(138) Replacing the chart around the sphere and joining its ends, so that it re-forms the transparent envelope, we may thrust a pin through at any point until it pierces the surface of the sphere. Indeed, the pin can be thrust deeper until it reaches the neutral axis, thus forming a scale of chroma for the color point where it enters (see paragraph 12). In the same way any colors on the sphere, within the sphere, or without it, can have pins thrust into the chart to mark their place, and the length by which each pin projects can be taken as a measure of chroma. If the chart is now unrolled, it retains the pins, which by their place describe the hue and value of a color, while their length describes its chroma.

Pins stuck into the score represent chroma.

(139) With this idea of the third color dimension incorporated in the score we can discard the pin, and record its length by a numeral. Any dot placed on the score marks a certain degree of hue and value, while a numeral beside it marks the degree of chroma which it carries, uniting with the hue and value of that point to give us a certain color. Glancing over a series of such color points, the eye easily grasps their individual character, and connects them into an intelligible series.

(140) Thus a flat chart becomes the projection of the color solid, and any color in that solid is transferred to the surface of the chart, retaining its degrees of hue, value, and chroma. So far the scales have been spoken of as divided into ten steps, but they may be subdivided much finer, if desired, by use of the decimal point. It is a question of convenience whether to make a small score with only the large divisions, or a much larger score with a hundred times as many steps. In the latter case each hue has ten steps, the middle step of green being distinguished as 5G-5/5 to suggest the four steps 1G, 2G, 3G, 4G, which precede it, and 6G, 7G, 8G, and 9G, which follow it toward blue-green.



The score preserves color records in a convenient shape.

Such a color score, or notation diagram, to be made small or large as the case demands, offers a very convenient means for recording color combinations, when pigments are not at hand.



(141) To display its three dimensions, a little model can be made with three visiting cards, so placed as to present their mutual intersection at right angles (Fig. 24).

5G 5/5 is their centre of mutual balance. A central plane separates all colors into two contrasted fields. To the right are all warm colors, to the left are all cool colors. Each of these fields is again divided by the plane of the equator into lighter colors above and darker colors below. These four color fields are again subdivided by a transverse plane through 5G 5/5 into strong colors in front and weak colors beyond or behind it.

(142) Any color group, whose record must all be written to the right of the centre, is warm, because red and yellow are dominant. One to the left of the centre must be cool, because it is dominated by blue. A group written all above the centre must have light in excess, while one written entirely below is dark to excess. Finally, a score written all in front of the centre represents only strong chromas, while one written behind it contains only weak chromas. From this we gather that a balanced composition of color preserves some sort of equilibrium, uniting degrees of warm and cool, of light and dark, and of weak and strong, which is made at once apparent by the dots on the score.

(143) A single color, like that of a violet, a rose, or a buttercup, appears as a dot on the score, with a numeral added for its chroma. A parti-colored flower, such as a nasturtium, is shown by two dots with their chromas, and a bunch of red and yellow flowers will give by their dots a color passage, or "silhouette," whose warmth and lightness is unmistakable.

The chroma of each flower written with the silhouette completes the record. The hues of a beautiful Persian rug, with dark red predominating, or a verdure tapestry, in which green is dominant, or a Japanese print, with blue dominant, will trace upon the score a pattern descriptive of its color qualities. These records, with practice, become as significant to the eye as the musical score. The general character of a color combination is apparent at a glance, while its degrees of chroma are readily joined to fill out the mental image.

(144) Such a plan of color notation grows naturally from the spherical system of measured colors. It is hardly to be hoped, in devising a color score, that it should not seem crude at first. But the measures forming the basis of this record can be verified by impartial instruments, and have a permanent value in the general study of color. They also afford some definite data as to personal bias in color estimates.

(145) This makes it possible to collect in a convenient form two contrasting and valuable records, one preserving such effects of color as are generally called pleasing, and another of such groups as are found unpleasant to the eye. Out of such material something may be gained, more reliable than the shifting, personal, and contradictory statements about color harmony now prevalent.



CHAPTER VII.

COLOR HARMONY.

Colors may be grouped to please or to give annoyance.

(146) Attempts to define the laws of harmonious color have not attained marked success, and the cause is not far to seek. The very sensations underlying these effects of concord or of discord are themselves undefined. The misleading formula of my student days—that three parts of yellow, five parts of red, and eight parts of blue would combine harmoniously—was unable to define the kind of red, yellow, and blue intended; that is, the hue, value, and chroma of each of these colors was unknown, and the formula meant a different thing to each person who tried to use it.

(147) It is true that a certain red, green, and blue can be united in such proportions on Maxwell discs as to balance in a neutral gray; but the slightest change in either the hue, value, or chroma, of any one of them, upsets the balance. A new proportion is then needed to regain the neutral mixture. This has already been shown in the discussion of triple balance (paragraph 82).

(148) Harmony of color has been still further complicated by the use of terms that belong to musical harmony. Now music is a measured art, and has found a set of intervals which are defined scientifically. The two arts have many points of similarity; and the impulses of sound waves on the ear, like those of light waves on the eye, are measured vibrations. But they are far apart in their scales, and differ so much in important particulars that no practical relationship can be set up. The intervals of color sensation require fit names and measures, ere their infinite variety can be organized into a fixed system.

(149) Any effort to compare certain sounds to certain colors soon leads to the wildest vagaries.

Harmony of sound is unlike harmony of color.

(150) The poverty of color language tempts to a borrowing from the richer terminology of music. Musical terms, such as "pitch, key, note, tone, chord, modulation, nocturne, and symphony," are frequently used in the description of color, serving by association to convey certain vague ideas.

(151) In the same way the term color harmony, from association with musical harmony, presents to the mind an image of color arrangement,—varied, yet well proportioned, grouped in orderly fashion, and agreeable to the eye. But any attempt to define this image in terms of color is disappointing. Here is a beautiful Persian rug: why do we call it beautiful? One says "because its colors are rich." Why are they rich? "Because they are deep in tone." What does that mean? The double-bass and the fog-horn are deep in tone, but not necessarily beautiful on that account. "Oh, no," says another, "it is all in one harmonious key." But what is a key of color? Is it made by all the values of one color, such as red, or by all the hues of equal value, such as the middle hues in our color solid?

(152) Certainly it is neither, for the rug has both light and dark colors; and, of the reds, yellows, greens, and blues, some are stronger and others weaker. Then what do we mean by a key of color? One must either continue to flounder about or frankly confess ignorance.

(153) Musical harmony explains itself in clear language. It is illustrated by fixed and definite sound intervals, whose measured relations form the basis of musical composition. Each key has an unmistakable character, and the written score presents a statement that means practically the same thing to every person of musical intelligence. But the adequate terms of color harmony are yet to be worked out.

Let us leave these musical analogies, retaining only the clue that a measured and orderly relation underlies the idea of harmony. The color solid which has been the subject of these pages is built upon measured color relations. It unites measured scales of hue, value, and chroma, and gives a definite color name to every sensation from the maxima of color-light and color-strength to their disappearance in darkness.

(154) Must not this theoretical color solid, therefore, locate all the elements which combine to produce color harmony or color discord?[32]

[Footnote 32: Professor James says there are three classic stages in the career of a theory: "First, it is attacked as absurd; then admitted to be true, but obvious and insignificant; finally it is seen to be so important that its adversaries claim to be its discoverers."]

(155) Instead of theorizing, let us experiment. As a child at the piano, who first strikes random and widely separated notes, but soon seeks for the intervals of a familiar air, so let us, after roaming over the color globe and its charts, select one familiar color, and study what others will combine with it to please the eye.

(156) Here is a grayish green stuff for a dress, and the little girl who is to wear it asks what other colors she may use with it. First let us find it on our instrument, so as to realize its relation to other degrees of color. Its value is 6,—one step above the equator of middle value. Its hue is green, G, and its chroma 5. It is written G 6/5.

(157) Color paths lead out from this point in every direction. Where shall we find harmonious colors, where discordant, where those paths most frequently travelled? Are there new ones still to be explored?

(158) There are three typical paths: one vertical, with rapid change of value; another lateral, with rapid change of hue; and a third inward, through the neutral centre to seek the opposite color field. All other paths are combinations of two or three of these typical directions in the color solid.

Three typical color paths.



(159) 1. The vertical path finds only lighter and darker values of gray-green,—"self-colors or shades," they are generally called,—and offers a safe path, even for those deficient in color sensation, avoiding all complications of hue, and leaving the eye free to estimate different degrees of a single quality,—color-light.

(160) 2. The lateral path passes through neighboring hues on either side. In this case it is a sequence from blue, through green into yellow. This is simply change of hue, without change of value or chroma if the path be level, but, by inclining it, one end of the sequence becomes lighter, while the other end darkens. It thus becomes an intermediate between the first and second typical paths, combining, at each step, a change of hue with a change of value. This is more complicated, but also more interesting, showing how the character of the gray-green dress will be set off by a lighter hat of Leghorn straw, and further improved by a trimming of darker blue-green. The sequence can be made still more subtle and attractive by choosing a straw whose yellow is stronger than the green of the dress, while a weaker chroma of blue-green is used in the trimming. This is clearly expressed by the notation thus: Y 8/7, G 6/5, BG 4/3, and written on the score by three dots and their chromas,—7, 5, and 3 (see Fig. 23).

(161) 3. The inward path which leads by increase of gray to the neutral centre, and on to the opposite hue red-purple, RP 4/5, is full of pitfalls for the inexpert. It combines great change of hue and chroma, with small change of value.

(162) If any other color point be chosen in place of gray-green, the same typical paths are just as easily traced, written by the notation, and recorded on the color score.

These paths trace sequences from any point in the color solid.

(163) In the construction of the color solid we saw that its scales were made of equal steps in hue, value, and chroma, and tested by balance on the centre of neutral gray. Any step will serve as a point of departure to trace regular sequences of the three types. The vertical type is a sequence of value only. It is somewhat tame, lacking the change of hue and chroma, but giving a monotonous harmony of regular values. The horizontal type traces a sequence of neighboring hues, less tame than the vertical type, but monotonous in value and chroma. The inward type connects opposite hues by a sequence of chroma balanced on middle gray, and is more stimulating to the eyes.

(164) These paths have so far been treated as made up of equal steps in each direction, with the accompanying idea of equal quantities of color at each step. But by using unequal quantities of color, the balance may be preserved by compensations to the intervals that separate the colors (see paragraphs 109, 110).

Unequal color quantities compensated by relations of hue, value, and chroma.

(165) Small bits of powerful color can be used to balance large fields of weak chroma. For instance, a spot of strong reddish purple is balanced and enhanced by a field of gray-green. So an amethyst pin at the neck of the girl's dress will appear to advantage with the gown, and also with the Leghorn straw. But a large field of strong color, such as a cloth jacket of reddish purple, would be fatal to the measured harmony we seek.

(166) This use of a small point of strong chroma, if repeated at intervals, sets up a notion of rhythm; but, in order to be rhythmic, there must be recurrent emphasis, "a succession of similar units, combining unlike elements." This quality must not be confused with the unaccented succession, seen in a measured scale of hue, value, or chroma.

Paper masks to isolate color intervals.

(167) A sheet of paper large enough to hide the color sphere may be perforated with three or more openings in a straight line, and applied against the surface, so as to isolate the steps of any sequence which we wish to study. Thus the sequence given in paragraph 160—Y 8/7, G 6/5, BG 4/3—may be changed to bring it on the surface of the sphere, when it reads Y 8/3, G 6/5, BG 5/5. A mask with round holes, spaced so as to uncover these three spots, relieves the eye from the distraction of other colors. Keeping the centre spot on green, the mask may be moved so as to study the effect of changing hue or value of the other two steps in the sequence.

(168) The sequence is lightened by sliding the whole mask upward, and darkened by dropping it lower. Then the result of using the same intervals in another field is easily studied by moving the mask to another part of the solid.

(169) Change of interval immediately modifies the character of a color sequence. This is readily shown by having an under-mask, with a long, continuous slit, and an over-mask whose perforations are arranged in several rows, each row giving different spaces between the perforations. In the case of the girl's clothing, the same sequence produces quite a different effect, if two perforations of the over-mask are brought nearer to select a lighter yellow-green dress, while the ends of the sequence remain unchanged. To move the middle perforation near the other end, selects a darker bluish green dress, on which the trimming will be less contrasted, while the hat appears brighter than before, because of greater contrast.

(170) The variations of color sequence which can thus be studied out by simple masks are almost endless; yet upon a measured system the character of each effect is easily described, and, if need be, preserved by a written record.

Invention of color groups.

(171) Experiments with variable masks for the selection of color intervals, such as have been described, soon stimulate the imagination, so that it conceives sequences through any part of the color solid. The color image becomes a permanent mental adjunct. Five middle colors, tempered with white and black, permit us to devise the greatest variety of sequences, some light, others dark, some combining small difference of chroma with large difference of hue, others uniting large intervals of chroma with small intervals of hue, and so on through a well-nigh inexhaustible series.

(172) As this constructive imagination gains power, the solid and its charts may be laid aside. We can now think color consecutively. Each color suggests its place in the system, and may be taken as a point of departure for the invention of groups to carry out a desired relation.

(173) This selective mental process is helped by the score described in the last chapter; and the quantity of each color chosen for the group is easily indicated by a variable circle, drawn round the various points on the diagram. Thus, in the case of the child's clothes, a large circle around G 6/5 gives the area of that color as compared with smaller circles around Y 8/7 and BG 4/3, representing the area of the straw and the trimming.

(174) When the plotting of color groups has become instinctive from long practice, it opens a wide field of color study. Take as illustration the wings of butterflies or the many varieties of pansies. These fascinating color schemes can be written with indications of area that record their differences by a simple diagram. In the same way, rugs, tapestries, mosaics,—whatever attracts by its beauty and harmony of color,—can be recorded and studied in measured terms; and the mental process of estimating hues, values, chromas, and areas by established scales must lead the color sense to finer and finer perceptions.

The same process serves as well to record the most annoying and inharmonious color groups. When sufficient of these records have been obtained, they furnish definite material for a contrast of the color combinations which please, with those that cause disgust. Such a contrast should discover some broad law of color harmony. It will then be in measured terms which can be clearly given; not a vague personal statement, conveying different meanings to each one who hears it.

Constant exercise needed to train the color sense.

(175) Appreciation of beautiful color grows by exercise and discrimination, just as naturally as fine perception of music or literature. Each is an outlet for the expression of taste,—a language which may be used clumsily or with skill.

(176) As color perception becomes finer, it discards the more crude and violent contrasts. A child revels in strong chromas, but the mark of a colorist is ability to employ low chroma without impoverishing the color effect. As a boy's shrieks and groans can be tempered to musical utterance, so his debauches in violent red, green, and purple must be replaced by tempered hues.

(177) Raphael, Titian, Velasquez, Corot, Chavannes, and Whistler are masters in the use of gray. Personal bias may lead one colorist a little more toward warm colors, and another slightly toward the cool field, in each case attaining a sense of harmonious balance by tempered degrees of value and chroma.[33]

[Footnote 33: "Nature's most lively hues are bathed in lilac grays. Spread all about us, yet visible only to the fine perception of the colorist, is this gray quality by which he appeals. Not he whose pictures abound in 'couleurs voyantes,' but he who preserves in his work all the 'gris colores' is the good colorist."

Translation from J. F. Rafaelli, in Annales Politiques & Litteraires.]

(178) It is not claimed that discipline in the use of subtle colors will make another Corot or Velasquez, but it will make for comprehension of their skill. It is grotesque to watch gaudily dressed persons going into ecstasies over the delicate coloring of a Botticelli, when the internal as well as the external evidence is against them.

(179) The colors which we choose, not only in personal apparel, but in our rooms and decorations, are mute witnesses to a stage of color perception.

If that perception is trained to finer distinctions, the mind can no longer be content with coarse expression. It begins to feel an incongruity between the "loud" color of the wall paper, bought because it was fashionable, and the quiet hues of the rug, which was a gift from some artistic friend. It sees that, although the furniture is covered with durable and costly materials, their color "swears" at that of the curtains and wood-work. In short, the room has been jumbled together at various periods, without any plan or sense of color design.

(180) Good taste demands that a room be furnished, not alone for convenience and comfort, but also with an eye to the beauty of the various objects, so that, instead of confusing and destroying the colors, each may enhance the other. And, when this sense of color harmony is aroused, it selects and arranges the books, the rugs, the lamp shade, the souvenirs of travel and friendship, the wall paper, pictures, and hangings, so that they fit into a color scheme, not only charming to the eye at first glance, but which continues to please the mind as it traces out an intelligent plan, bringing all into general harmony.

(181) Nor will this cease when one room has been put to rights. Such a coloristic attitude is not satisfied until the vista into the next apartment is made attractive. Or should there be a suite of rooms, it demands that, with variety in each one, they all be brought into harmonious sequence. Thus the study of color finds immediate and practical use in daily life. It is a needed discipline of color vision, in the sense that geometry is a discipline of the mind, and it also enters into the pleasure and refinement of life at every step. Skill or awkwardness in its use exerts as positive an influence upon us as do the harmonies and discords of sound, and a far more continuous one. It is thought a defect to be unmusical. Should it not be considered a mark of defective cultivation to be insensitive to color?

(182) In this slight sketch of color education it has been assumed that we are to deal with those who have normal perceptions. But there are some who inherit or develop various degrees of color-blindness; and a word in their behalf may be opportune.

(183) A case of total color-blindness is very rare, but a few are on record. When a child shows deficient color perception,[34] a little care may save him much discomfort, and patient training may correct it. If he mismatches some hues, confuses their names, seems incapable of the finer distinctions of color, study to find the hues which he estimates well, and then help him to venture a little into that field where his perception is at fault. Improvement is pretty sure to follow when this is sympathetically done. One student, who never outgrew the habit of giving a purplish hue to all his work, despite many expedients and the use of various lights and colored objects to correct it, is the single exception among hundreds whom it has been my privilege to watch as they improved their first crude estimates, and gained skill in expressing their sense of Nature's subtle color.

[Footnote 34: See Color Blindness in Glossary.]

(184) To sum up, the first chapter suggests a measured color system in place of guess-work. The next describes the three color qualities, and sketches a child's growth in color perception. The third tells how colors may be mingled in such proportions as to balance. After the impracticability of using spectral color has been shown in the fourth chapter, the fifth proceeds to build a practical color solid. The sixth provides for a written record of color, and the last applies all that has preceded to suggestions for the study of color harmony.

(185) Wide gaps appear in this outline. There is much that deserves fuller treatment. But, if the search for refined color and a clearer outlook upon its relations are stimulated by this fragmentary sketch, some of its faults may be overlooked.





PART II.

A COLOR SYSTEM AND COURSE OF STUDY BASED ON THE COLOR SOLID AND ITS CHARTS.

Arranged for nine years of school life.

GLOSSARY OF COLOR TERMS.

Taken from the Century Dictionary.

INDEX

(by paragraphs).





A COLOR SYSTEM WITH COURSE OF STUDY BASED ON THE COLOR SOLID AND ITS CHARTS

See Chapter II.

Copyright, 1904, by A. H. Munsell.



A COLOR SYSTEM AND COURSE OF STUDY

BASED ON THE COLOR SOLID AND ITS CHARTS, ADAPTED TO NINE YEARS OF SCHOOL LIFE.

Gr. Grade Ill. Illustration App. Application Mat. Materials

==================================================================== Gr. Subject. Colors Studied. Ill. App. Mat. + -+ -+ -+ -+ - 1. HUES Red. R. Sought in Borders Colored of Yellow. Y. Nature and crayons color. Green. G. and Art. Rosettes. and Blue. B. papers. Purple. P. + -+ -+ -+ -+ - 2. HUES Yellow-red. YR. Sought in Borders Colored of Green-yellow. GY. Nature and crayons color. Blue-green. BG. and Art. Rosettes. and Purple-blue. PB. papers. Red-purple. RP. + -+ -+ -+ -+ - 3. VALUES Light, middle, Sought in Design. Color of and dark R. Nature sphere. color. " " Y. and Art. " " G. " " B. " " P. + -+ -+ -+ -+ - 4. VALUES 5 values of YR.} Sought in Design. Charts. of " " " GY.} Nature color. " " " BG.} and Art. " " " PB.} " " " RP.} 9/, 7/, 5/, 3/, 1/. + -+ -+ -+ -+ - 5. CHROMAS 3 chromas of R5/. Sought in Design. Charts. of " " " Y5/. Nature color. " " " G5/. and Art " " " B5/. " " " P5/. + -+ -+ -+ -+ - 6. CHROMAS 3 chromas of YR5/. Sought in Design Color of " " " GY5/. Nature Tree. color. " " " BG5/. and Art. " " " PB5/. " " " RP5/. " " " R7/ and R3/.} " Y7/ " Y3/.} " G7/ " G3/.} " B7/ " B3/.} " P7/ " P3/.} + -+ -+ -+ -+ - 7. To OBSERVE IMITATE & WRITE color by HUE, VALUE, and CHROMA " " Paints. + - 8. QUANTITY of color. Pairs of equal area and unequal area " " Paints. Balanced by HUE, VALUE, and CHROMA. + - 9. QUANTITY of color. Triads of equal area and unequal area " " Paints. Balanced by HUE, VALUE, and CHROMA. ====================================================================

Copyright, 1904, by A. H. Munsell.

STUDY OF SINGLE HUES AND THEIR SEQUENCE. Two Years.

FIRST GRADE LESSONS.

1. Talk about familiar objects, to bring out color names, 2. as toys, flowers, clothing, birds, insects, etc. 3. Show soap bubbles and prismatic spectrum. 4. Teach term HUE. Hues of flowers, spectrum, plumage of birds, etc. 5. Show MIDDLE[35] RED. Find other reds. 6. Show MIDDLE YELLOW. Find other yellows, and compare with reds. 7. Show MIDDLE GREEN. Find other greens, " with reds and yellows. 8. Show MIDDLE BLUE. Find other blues, " with preceding hues. 9. Show MIDDLE PURPLE. Find other purples, " with preceding hues. 10-15. Review FIVE MIDDLE HUES,[35] match with colored papers, and place in circle. 16-20. Show COLOR SPHERE. Find sequence of five middle hues. Memorize order. 21. Middle red imitated with crayon, named and written by initial R. 22. Middle yellow " " " " by initial Y. 23. Middle green " " " " by initial G. 24. Middle blue " " " " by initial B. 25. Middle purple " " " " by initial P. 26-30. Review, using middle hues[35] in borders and rosettes for design.

Aim.—To recognize sequence of five middle hues. To name, match, imitate, write, and arrange them.

SECOND GRADE LESSONS.

1-3. Review sequence of five middle hues.[35] 4. Show a hue INTERMEDIATE between red and yellow. Find it in objects. 5. Compare with red and yellow. 6. Recognize and name YELLOW-RED. Match, imitate, and write YR. 7-8. Show GREEN-YELLOW between green and yellow. Treat as above, and write GY. 9-10. Show BLUE-GREEN between blue and green. " " and write BG. 11-12. Show PURPLE-BLUE between purple and blue. " " and write PB. 13-14. Show RED-PURPLE between red and purple. " " and write RP. 15-20. Make circle of ten hues. Place Intermediates, and memorize order so as to repeat forward or backward. Match, imitate, and write by initials. 21-25. Find sequence of ten hues on COLOR SPHERE. Compare with hues of natural objects. 26-30. Review, using any two hues in sequence for borders and rosettes.

Aim.—To recognize sequence of ten hues, made up of five middle[35] hues and the five intermediates. To name, match, write, imitate, and arrange them.

[Footnote 35: The term MIDDLE, as used in this course of color study, is understood to mean only the five principal hues which stand midway in the scales of VALUE and CHROMA. Strictly speaking, their five intermediates are also midway of the scales; but they are obtained by mixture of the five principal hues, as shown in their names, and are of secondary importance.]

STUDY OF SINGLE VALUES AND THEIR SEQUENCE. Two Years.

THIRD GRADE LESSONS.

1. Review sequence of ten hues. 2. Recognize, name, match, imitate, write, and find them 3. on the COLOR SPHERE. Also in objects. 4. Teach use of term VALUE. Color value recognized apart from color hue. 5. Find values of red, lighter and darker than the middle value already familiar. 7. THREE VALUES of RED. Find on sphere. Name as LIGHT, MIDDLE, and DARK values of red. 8. THREE VALUES of RED. Imitate with crayons, and write them as 3, 5, and 7. 9. THREE VALUES of YELLOW. Compare with above. 10. Recognize, name, match, and imitate with crayons. 11. THREE VALUES of GREEN. Compare, and treat as above. 12. Find on sphere and in objects. 13. THREE VALUES of BLUE. " " 14. 15. THREE VALUES of PURPLE. " " 16. 17-20. Review, combining two values and a single hue for design.[36]

Aim.—To recognize a sequence combining three values and five middle hues. To name, match, imitate, and arrange them.

[Footnote 36: These ten lessons in this and succeeding grades are devoted to color perception only. Their application to design is a part of the general course in drawing, and will be so considered in the succeeding grades. Note that, although thus far nothing has been said about complementary hues, the child has been led to associate them in opposite pairs by the color sphere. (See Chapter III., p. 76.)] [[Error for "paragraph 76"]]

FOURTH GRADE LESSONS.

1. Review sequence of three values in each of the five middle hues. 2. To recognize, name, match, imitate, and 3. find them on sphere and in objects. 4. Show FIVE VALUES of RED. Find them on large color sphere. 5. Number them 1, 3, 5, 7, 9. Match, imitate, and write. 6. Show FIVE VALUES of BLUE-GREEN. " " " Treat as above and review. 7. Show FIVE VALUES of PURPLE-BLUE compared with Yellow. Treat as above and review. 8. Show FIVE VALUES of RED-PURPLE " Green. Treat as above and review. 9. Show FIVE VALUES of YELLOW-RED " Blue. Treat as above and review. 10. Show FIVE VALUES of GREEN-YELLOW " Purple. Treat as above and review.

Aim.—To recognize sequences combining five values in each of ten hues. To name, match, imitate, WRITE, and arrange them.

STUDY OF SINGLE CHROMAS AND THEIR SEQUENCES. Two Years.

FIFTH GRADE LESSONS.

1. Review sequences of hue and value. Find them on the color sphere. Name, match, imitate, write, and arrange them by hue and value. 2. Teach use of term CHROMA. Compare three chromas with three values of red. Name them WEAK, MIDDLE, and STRONG chromas. Find in nature and art. 3. THREE CHROMAS of RED. Compare with three of blue-green. 4. Show COLOR TREE. Suggest unequal chroma of hues. 5. THREE CHROMAS of YELLOW. Compare with three chromas of purple-blue. 6. THREE CHROMAS of GREEN. " " red-purple. 7. THREE CHROMAS of BLUE. " " yellow-red. 8. THREE CHROMAS of PURPLE. " " green-yellow. 9. Arrange five middle hues in circle, described as on the surface of the Color Sphere (middle chroma), with weaker chromas inside, and stronger chromas outside, the sphere. 10. Review,—to find these sequences of chroma in nature and art.

Aim.—To recognize sequences combining three chromas, middle value, and ten hues. To name, match, imitate, and arrange them.

SIXTH GRADE LESSONS.

1. Review sequences combining three chromas, five hues, and middle value. Find on Color Tree, name, match, imitate, and arrange them. 2. THREE CHROMAS of LIGHTER and DARKER RED. Compare with middle red. 3. Write " " " " as a fraction, chroma under value, using 3, 5, and 7. Thus R 5/7. 4. Find CHROMAS of LIGHTER RED, and compare with darker blue-green. 5. THREE CHROMAS of LIGHTER and DARKER YELLOW, with purple-blue. 6. " " " " GREEN, " red-purple. 7. " " " " BLUE, " yellow-red. 8. " " " " PURPLE, " green-yellow. 9. Colors in nature and art, defined by hue, value, and chroma. Named, matched, imitated, written, and arranged by Color Sphere and Tree. 10. Review,—to find sequences combining three chromas, five values, and ten hues.

Aim.—To recognize sequences of chroma, as separate from sequences of hue or sequences of value. To name, match, write, imitate, and arrange colors in terms of their hue, value, and chroma.

COLOR EXPRESSION IN TERMS OF THE HUES, VALUES, AND CHROMAS.

SEVENTH GRADE LESSONS.

1. Review sequences of hue (initial), value (upper numeral), & chroma (lower numeral). 2. " " " " 3. Exercises in expressing colors of natural objects by the NOTATION, 4. and tracing their relation by the spherical solid. 5. REDS in Nature and Art, imitated, written, and traced by the spherical solid. 6. YELLOWS in Nature and Art, " " by the spherical solid. 7. GREENS in Nature and Art, " " by the spherical solid. 8. BLUES in Nature and Art, " " by the spherical solid. 9. PURPLES in Nature and Art, " " by the spherical solid. 10. ONE COLOR PAIR selected, defined, and arranged for design. (See note 4th Grade.)

Aim.—To define any color by its hue, value, and chroma. To imitate with pigments and write it.

EIGHTH GRADE LESSONS.

1. Review sequences, and select colors which balance. Illustrate the term. 2. BALANCE of light and dark,—weak and strong,—hot and cold colors. 3. RED and blue-green balanced in hue, value, and chroma, with EQUAL AREAS. 4. YELLOW and purple-blue " " with EQUAL AREAS. 5. GREEN and red-purple " " with EQUAL AREAS. 6. BLUE and yellow-red " " with EQUAL AREAS. 7. PURPLE and green-yellow " " with EQUAL AREAS. 8. UNEQUAL AREAS of the above pairs, balanced by compensating 9. qualities of hue, value, and chroma. Examples from nature and art. 10. ONE COLOR PAIR of unequal areas selected, defined, and used in design.

Aim.—To BALANCE colors by area, hue, value, and chroma. To imitate with pigments and write the balance by the notation.

NINTH GRADE LESSONS.

1. Review balance of color pairs, by area, hue, value, and chroma. 2. To recognize, name, imitate, write, and record them. 3. SELECTION of two colors to balance a given RED. 4. " " " " YELLOW. 5. " " " " GREEN. 6. " " " " BLUE. 7. " " " " PURPLE. 8-10. TRIAD of color, selected, balanced, written, and used in design.

Aim.—To recognize triple balance of color, and express it in terms of area, hue, value, and chroma. Also to use it in design.



GLOSSARY OF COLOR TERMS

TAKEN FROM THE

CENTURY DICTIONARY.



GLOSSARY

The color definitions here employed are taken from the Century Dictionary. Special attention is called to the cross references which serve to differentiate HUE, VALUE, and CHROMA.

AFTER IMAGE.—An image perceived after withdrawing the eye from a brilliantly illuminated object. Such images are called positive when their colors are the same as that of the object, and negative when they are its complementary colors.

BLUE.—Of the color of the clear sky; of the color of the spectrum between wave lengths .505 and .415 micron, and more especially .487 and .460; or of such light mixed with white; azure, cerulean.

BLACK.—Possessing in the highest degree the property of absorbing light; reflecting and transmitting little or no light; of the color of soot or coal; of the darkest possible hue; sable. Optically, wholly destitute of color, or absolutely dark, whether from the absence or the total absorption of light. Opposed to white.

BROWN.—A dark color, inclined to red or yellow, obtained by mixing red, black, and yellow.

CHROMA.—The degree of departure of a color sensation from that of white or gray; the intensity of distinctive hue; color intensity.

CHROMATIC.—Relating to or of the nature of color.

COBALT BLUE.—A pure blue tending toward cyan blue and of high luminosity; also called Hungary blue, Lethner's blue, and Paris blue.

COLOR.—Objectively, that quality of a thing or appearance which is perceived by the eye alone, independently of the form of the thing; subjectively, a sensation peculiar to the organ of vision, and arising from the optic nerve.

COLOR BLINDNESS.—Incapacity for perceiving colors, independent of the capacity for distinguishing light and shade. The most common form is inability to perceive red as a distinct color, red objects being confounded with gray or green; and next in frequency is the inability to perceive green.

COLOR CONSTANTS.—The numbers which measure the quantities, as well as any other system of three numbers for defining colors, are called constants of color.

COLOR VARIABLES.—Colors vary in CHROMA, or freedom from admixture of white light; in BRIGHTNESS, or luminosity; and in HUE, which roughly corresponds to the mean wave length of the light emitted.

COLORS, COMPLEMENTARY.—Those pairs of color which when mixed produce white or gray light, such as red and green-blue, yellow and indigo-blue, green-yellow and violet.

COLORS, PRIMARY.—The red, green, and violet light of the spectrum, from the mixture of which all other colors can be produced. Also called fundamental colors.

DYESTUFFS.—In commerce, any dyewood, lichen, or dyecake used in dyeing and staining.

ELECTRIC LIGHT.—Light produced by electricity and of two general kinds, the arc light and the incandescent light. In the first the voltaic arc is employed. In the second a resisting conductor is rendered incandescent by the current.

ENAMEL.—In the fine arts a vitreous substance or glass, opaque or transparent, and variously colored, applied as a coating on a surface of metal or of porcelain.

GRATING, DIFFRACTION.—A series of fine parallel lines on a surface of glass, or polished metal, ruled very close together, at the rate of 10,000 to 20,000 or even 40,000 to the inch; distinctively called a diffraction or a diffraction grating, much used in spectroscopic work.

GRAY.—A color having little or no distinctive hue (CHROMA) and only moderate luminosity.

GREEN.—The color of ordinary foliage; the color seen in the solar spectrum between wave lengths 0.511 and 0.543 micron.

EMERALD GREEN.—A highly chromatic and extraordinarily luminous green of the color of the spectrum at wave length 0.524 micron. It recalls the emerald by its brilliancy, but not by its tint; applied generally to the aceto-arsenate of copper. Usually known as Paris green.

HIGH COLOR.—A hue which excites intensely chromatic color sensations.

HUE.—Specifically and technically, distinctive quality of coloring in an object or on a surface; the respect in which red, yellow, green, blue, etc., differ one from another; that in which colors of equal luminosity and CHROMA may differ.

INDIGO.—The violet-blue color of the spectrum, extending, according to Helmholtz, from G two-thirds of the way to F in the prismatic spectrum. The name was introduced by Newton, but has lately been discarded by the best writers.

LIGHT.—Adjective applied to colors highly luminous and more or less deficient in CHROMA.

LUMINOSITY.—Specifically, the intensity of light in a color, measured photometrically; that is to say, a standard light has its intensity, or vis viva, altered, until it produces the impression of being equally bright with the color whose light is to be determined; and the measure of the vis viva of the altered light, relatively to its standard intensity, is then taken as the luminosity of the color in question.

MAXWELL COLOR DISCS.—Discs having each a single color, and slit radially so that one may be made to lap over another to any desired extent. By rotating these on a spindle, the effect of combining certain colors in varying proportions can be studied.

MICRON.—The millionth part of a metre, or 1/23400 of an English inch. The term has been formally adopted by the International Commission of Weights and Measures, representing the civilized nations of the world, and is adopted by all metrologists.

ORANGE.—A reddish yellow color, of which the orange is the type.

VISION, PERSISTENCE OF.—The continuance of a visual impression upon the retina of the eye after the exciting cause is removed. The length of time varies with the intensity of the light and the excitability of the retina, and ordinarily is brief, though the duration may be for hours, or even days. The after image may be either positive or negative, the latter when the bright part appears dark and the colored parts in their corresponding contrast colors. It is because of this persistence that, for example, a firebrand moved very rapidly appears as a band or circle of light.

PHOTOMETER.—An instrument used to measure the intensity of light. Specifically, to compare the relative intensities of the light emitted from various sources.

PIGMENT.—Any substance that is or can be used by painters to impart color to bodies.

PINK.—A red color of low chroma, but high luminosity, inclining toward purple.

PRIMARY COLORS.—See Colors, primary.

PURE COLOR.—A color produced by homogeneous light. Any very brilliant or decided color.

PURPLE.—A color formed by the mixture of blue and red, including the violet of the spectrum above wave length 0.417, which is nearly a violet blue, and extending to, but not including, crimson.

RAINBOW.—A bow or an arc of a circle, consisting of the prismatic colors, formed by the refraction and the reflection of rays of light from drops of rain or vapor, appearing in the part of the heavens opposite to the sun.

RED.—A color more or less resembling that of blood, or the lower end of the spectrum. Red is one of the most general color names, and embraces colors ranging in hue from aniline to scarlet iodide of mercury and red lead. A red yellower than vermilion is called scarlet. One much more crimson is called crimson red. A very dark red, if pure or crimson, is called maroon; if brownish, chestnut or chocolate. A pale red—that is, one of low CHROMA and high LUMINOSITY—is called a pink, ranging from rose pink or pale crimson to salmon pink or pale scarlet.

VENETIAN RED.—An important pigment used by artists, somewhat darker than brick red in color, and very permanent.

RETINA.—The innermost and chiefly nervous coat of the posterior part of the eyeball.

SATURATION, OF COLORS.—In optics the degree of admixture with white, the saturation diminishing as the amount of white is increased. In other words, the highest degree of saturation belongs to a given color when in the state of greatest purity.

SCALE.—A graded system, by reference to which the degree, intensity, or quality of a sense perception may be estimated.

SHADE.—Degree or gradation of defective luminosity in a color, often used vaguely from the fact that paleness, or high luminosity, combined with defective CHROMA, is confounded with high luminosity by itself. See Color, Hue, and Tint.

SPECTRUM.—In physics the continuous band of light showing the successive prismatic colors, or the isolated lines or bands of color, observed when the radiation from such a source as the sun or an ignited vapor in a gas flame is viewed after having been passed through a prism (prismatic spectrum) or reflected from a diffraction grating (diffraction or interference spectrum). See Rainbow.

TINT.—A variety of color; especially and properly, a luminous variety of low CHROMA; also, abstractly, the respect in which a color may be raised by more or less admixture of white, which at once increases the luminosity and diminishes the CHROMA.

TONE.—A sound having definiteness and continuity enough so that its pitch, force, and quality may be readily estimated by the ear. Musical sound opposed to noise. The prevailing effect of a color.

ULTRAMARINE.—A beautiful natural blue pigment, obtained from the mineral lapis-lazuli.

VALUE.—In painting and the allied arts, relation of one object, part, or atmospheric plane of a picture to the others, with reference to light and shade, the idea of HUE being abstracted.

VERMILION.—The red sulphate of mercury.

VIOLET.—A general class of colors, of which the violet flower is a highly chromatic example. The sensation is produced by a pure blue whose CHROMA has been diminished while its LUMINOSITY has been increased. Thus blue and violet are the same color, though the sensations are different. A mere increase of illumination may cause a violet blue to appear violet, with a diminution of apparent CHROMA. This color, called violet or blue according to the quality of the sensation it excites, is one of the three fundamental colors of Young's theory. A deep blue tinged with red.

VIRIDIAN.—Same as Veronese green.

WHITE.—A color transmitting, and so reflecting to the eye, all the rays of the spectrum, combined in the same proportion as in the impinging light.

YELLOW.—The color of gold and of light, of wave length 0.581 micron. The name is restricted to highly chromatic and luminous colors. When reduced in CHROMA, it becomes buff; when reduced in LUMINOSITY, a cool brown. See Brown.

VERONESE GREEN.—A pigment consisting of hydrated chromium sesquioxide. It is a clear bluish green of great permanency. Also called Viridian.



INDEX BY PARAGRAPHS.

Balance of color, 23, 47, 67, 75-77, 81-86, 106, 108, 111, 114, 132, 136, 142, 147, Appendix III. Black, 12, 16, 22, 31, 41, 54, 55, 65, 91, 119. Blue, 9, 12, 16, 34, 104, 146, 147. Brewster's theory, Appendix III.

Charts of the color sphere, 14, 17, 126, 127, 135, 136, 140. Chevreul, Appendix III., V. Chroma, 3, 4, 8, 11, 14, 21-24, 28, 39, 40, 42, 45, 64, 76, 78, 82, 88, 94, 95, 105, 121, 132. Scale of, 12, 19, 25, 31-35, 42, 133. Strongest, 32, 34, 42. Chromatic tuning fork, 117, 118, 119-127. Circuit, inclined, 16, 17, 97. Color, apparatus, 3, 8, 14, 132. Atlas, 129. Balance, 23, 47, 67, 75-77, 81-86 (triple), 106, 108, 111, 114, 132, 136, 142, 147. Blindness, 182, 183. Charts, 14, 17, 126, 127, 135, 136, 140. Circuit, 54, 58, 59. Complementary, 76, 77. Color, dimensions of, 3, 8, 9, 13, 25, 53, 94, 116. Curves, 94. Discs, Maxwell's, 76, 93, 106-112, 113, 117. Harmony, 47, 77, 86, 145-148, 151-174, 180. Hand as a holder of, 54-58. Key of, 6, 151, 152. Language, poverty of, 5, 175. Lists, 131. Measured, 3, 14, 32. Meridians, 136, 137. Middle, 28, 29, 40-42, 113. Misnomers, Appendix I. Mixture, 56-72. Names, 1, 2, 14, 19, 25, 90, 91, 131. Notation, 36, 37, 40-42, 47, 67, 72, 86, 101, 133. Orange, 9-11, 89, 123. Parallels, 12, 119. Paths, 157, 158, 160-164. Perception, 27, 29, 39, 179. Principal (5), 4, 16, 21, 26, 31, 34, 40, 54, 56, 57. Principal (5) and intermediates (5), 31, 60, 68, 112, 134. Purity, 8, 19, 23, 89, 98, 99. Records 145. Relations, 14, 24, 36, 37, 153. Rhythm, 166. Scale, 3, 7, 24, 30, 55, 120, 140, Appendix II. Score, 133-139, 142, 173. Sensations, 3, 4, 15, 19, 21, 87. Sequences, 47, 78, 79, 120, 156, 169-171, 181. Sir Isaac Newton's, 89. Schemes, Appendix V. Solid, 14, 19, 102, 126, 129, 140, 153. Spectral, 16, 88, 94, 129. Sphere, 12-17, 24, 25, 31, 43, 55, 72, 91, 101, 102, 111, 122, 132. Standard, 4, 26, 35. System, 3, 8, 28, 123, 130. Need of, 46, 148. Tree, 14, 30-34, 43, 94, 95, 124. Waves, 21, 23, 136. Tones, 134. Children's color studies, Appendix IV. Colorist, 84, 121, 177. Coloristic art, 7, 38, 45, 177. Combined scales, 12, 14, 36, 37, 47. Complements, 76, 77. Course of color study, 48-50.

Daylight photometer, 22, 103, 119.

Enamels, 28, 29, 101, 117.

Fading, 8, 23. False color balance, Appendix III. Flat diagrams, 14. Fundamental sensations, 28, Appendix III.

Green, 2, 32, 104, 136, 137, 140, 147, 148.

Hue, 3, 4, 8, 9-11, 14, 18, 21-26, 34, 39, 40, 43, 54, 59, 76, 82, 89, 105. Scale of, 12, 19, 25, 31, 35, 120, 133.

Ideal color system, 100.

Lambert's pyramid, note to 31. Luminist, 121.

Masks, 47, 167-171. Maxwell discs, 93, 107, 113, 117. Measurement of colors, 3, 8, 14, 116, Appendix IV. Middle gray, 61, 65, 72. Middle hues, 10, 28, 65. Mixture of hues, 56-72. Musical terms used for colors, 6, 46, 148-150.

Neutral axis, 31, 34, 61, 65, 121. Neutral gray, 11, 23, 25, 62, 64, 65, 72, 114, 102. Notation diagram, 140.

Orange, 9-11, 18, 123.

Personal bias, 144, 174. Pigments, 14, 27-29, 101-104, 125, 129. Photometer, 65. Primary sensations, 89. Prismatic color sphere, 98. Purple, 5.

Rainbow, 15, 17. Red, middle, 1, 32, 41, 60, 66, 72, 104, 110, 122, 147, 148. Retina, 21. Rood, modern chromatics, Appendix I. Runge, note to 31, Appendix V.

Shades and tints, 22. Spectrum, solar, 15-18, 27, 28, 87, 88, 92, 95, 96.

Tone, 6.

Value, 3, 8-11, 14, 21-24, 28, 34, 39, 40-43, 54, 76, 78, 82, 94, 105, 120, 132. Scale of, 12, 19, 25, 31, 34, 35, 64, 102, 120, 133. Vermilion, 42, Appendix III. Vertical (neutral) axis, 12, 25, 31, 34, 65, 68. Violet, 90.

Warm and cold colors, 72, 123, note to 136, 137, 138. Wave lengths, 21, 22, 23, 89. White, 12, 16, 17, 22, 31, 41, 54, 55, 65, 87, 91, 92, 99, 119.

Yellow, 1, 32, 54, 104, 136.



The MUNSELL PHOTOMETER

Patented November 19, 1901

A portable, daylight instrument, adapted to laboratory work in general, and of especial service in the comparison of color values. Placed in the course of Optical Measurements at the Massachusetts Institute of Technology

Price, $50

[Decoration]

IN PREPARATION

A COLOR ATLAS

Also text-books and models specially designed to serve in the education of the color sense

THE END