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COLOR DEFINITIONS.

the light impinging upon it. Therefore if we take absolute re- flection as 100 a fraction of 100 will give the relative lumi- nosity of any body." Luminosity is another expression of the quality above described as forming a prominent feature in the term values.

Potentiality. — The ability or strength of a color to affect other colors by combinations with them. For example, white has a greater potentiality than black, yellow greater than red, and violet the least of all the spectrum colors.

It is a pertinent question whether any quality is involved in this term which is not found in value, tone and luminosity, but it expresses a somewhat different phase of a line of color effects.

Quality. — This term seems to be used rather indefinitely when applied to color, but perhaps it is not far removed from the term hue or kind of color.