The Spectrum Sequence and the Circuit of the Colors
135. Having produced the scale of twelve colors in the values of their greatest intensities, and as intense as possible, we get an approximation to the Spectrum with this difference, that the color Violet-Red (Purple) which we get in pigments and mixtures of pigments does not occur in the Spectrum and, so far as we know, does not belong in the Spectrum. We have in the Spectrum a sequence which begins with Red and ends with Violet. It is a sequence, not a circuit. In pigment-mixtures, however, we have a circuit, clearly enough, and Violet-Red is a connecting link between Violet and Red.