A systematic arrangement of colors in terms of hue, saturation, and brightness, used as a reference standard.The system arose from the need for a single standard of comparison so that color specifications could be clearly stated and carried out in industry. Manufacturers had a great deal of trouble in the early part of this century because there were a number of different standards instead of a uniform means of defining any particular color. A. H. MunseU studied the problem and proposed a single system in 1915. He later refined and restated his standards in the Munsell Book of Color, published in 1929. In this system every color is classified and numbered according to the three dimensions of hue, saturation (“chroma”), and brightness (“value”). These dimensions are marked off on charts in equal-appearing gradations.To find these equal-appearing gradations, Munsell prepared sets of cards which showed every color in different degrees of saturation (richness) and brightness. He then gave the cards for each color to a group of subjects, and asked them to divide them, first into equal steps of increasing brightness, and after that into steps of increasing saturation. The resulting gradations were then arranged in systematic order, and a number was assigned to each of them. The book reproduces these gradations in the form of rectangular slips of heavy paper painted with permanent water color. Any color that can be reproduced by mixing pigments can be found in it, and any manufacturer who needs to produce standard colors merely has to refer to a number in the Munsell System. See color circle, color SOLID