PLATE I. 
I. — Primary Combinations. 
The primaries here used are : — 
Yellow — light cadmium. 
Red — scarlet vermilion + madder carmine. 
Blue — ultramarine. 
The secondaries, however, are not all of them produced by the mixture 
of the pigments used as primaries, the orange being orange cadmium, and 
the purple, aniline violet. This is necessary on account of the impurity ol 
the red. 
II. — Secondary Combinations. 
The pure secondaries in this figure are the same as those in the one 
above. The tertiaries, however, are here in each case actual mixtures of 
the pigments. 
