Page:Elementary Color (IA gri c00033125012656167).djvu/64

 with their tops. Also the computation of the proportion of green and blue when raised to the full circle may form a prac- tical problem in proportion for pupils of the higher grades. Taken together, these experiments prove that the complemen- taries of the old primaries are not found in the secondaries.

The last claim of the Brewster theory is that the secondaries by combination form three lines of colors peculiar to them- selves, called citrines, russets and olives. It is asserted that the mixture of orange and green makes citrine ; orange and violet russet ; green and violet olive. Although these names may be very convenient terms to express three general classes of colors, they must of necessity be too general and indefiuite to be of value for accurate expression of color effects, and are in fact so vague that hardly two persons can be found in a large company who will agree as to the best expression of either of them. The following are formulas for a number of colors in each class, as made from analyses of colors coining under these names. It is an interesting exercise to produce some of these colors by means of the rotating color disks and test the opinions of the different members of a company as to which best represents to each one of them a tertiary color, as citrine, for example. For this purpose three different formulas may be shown at the same time, with three sizes of disks.