The quality in a painting which is known as "values" may quite easily be regarded by the printer as signifying to him the same as tone. Careful study will show him that there is a difference, and also that value is a vital element in his work which has for him a real significance. Value may not unfairly be considered to be an element of tone. It relates to the intensity of light; not the brilliancy of color, but the capacity that resides in color to reflect light. In color printing the value of the most common colors ranks with yellow first, then orange, green, red, blue, and violet. That is, yellow is capable of reflecting more light from the same quantity of sunlight than any other color, and violet less than any other color. Scientists have reckoned that chrome yellow reflects 80 per cent of light, green 40 per cent, etc. These figures serve no very practical purpose, because the reflecting power of any tint is dependent upon the other colors employed. Colors are dependent upon each other for their value as well as for their intensity and their harmony. It is not difficult to treat this matter of value in a mathematical way, as is suggested by Prof. J. C. Van Dyke: "Let the chrome yellow with its 80 per cent of light represent a sunset sky in the background; let the green with its 40 per cent represent the grass in the immediate foreground; and let the orange-red with its 60 per cent represent the sail of a Venetian fishing vessel upon the water of the middle distance. Now we have the three leading pitches of light in the three planes of the picture," and the problem would stand thus: 40:60::60:80 and the result will indicate the relative power of the value in the picture.

Interesting, but not especially useful, the "practical" printer says. No, not unless there is recognizable in this, as in all that has been said about art in printing, the subtle relation between the vital elements of graphic art and those refinements of knowledge and practice which tend to bring printing nearer to the arts. The connection is there, and is evident to the seeing eye. In nature and in life the sense of values is of such importance that without it objects would not have relative positions; all would be a jumble of shades and tones, objects and colors; we would stumble, as we could not see depressions; we would grasp an arm or the empty air, when we attempted to seize a hand; we could not judge distances. It is upon the extent and the thoroughness of the printer's knowledge of this question of values that the degree of refinement and truth he is able to impart to a certain class of work depends, and hence its money value to him and its intrinsic value to his patrons.