for every
color based upon its intrinsic qualities, and free from terms purloined
in other sensations, or caught from the fluctuating colors of natural
objects.

[Footnote 5: For description of the Color Tree see paragraphs 33
and 34.]

+How this system describes the spectrum.+

(15) The solar spectrum and rainbow are the most stimulating color
experiences with which we are acquainted. Can they be described by this
solid system?

(16) The lightest part of the spectrum is a narrow field of greenish
yellow, grading into darker red on one side and into darker green upon
the other, followed by still darker blue and purple. Upon the sphere the
values of these spectral colors trace a path high up on the yellow
section, near white, and slanting downward across the red and green
sections, which are traversed near the level of the equator, it goes on
to cross the blue and purple well down toward black.

(17) This forms an inclined circuit, crossing the equator at opposite
points, and suggests the ecliptic or the rings of Saturn (see outside
cover). A pale rainbow would describe a slanting circuit nearer white,
and a dimmer one would fall within the sphere, while an intensely
brilliant spectrum projects far beyond the surface of the sphere, so
greatly is the chroma of its hues in excess of the common pigments with
which we work out our problems.

(18) At the outset it is well to recognize the place of the spectrum in
this system, not only because it is the established basis of scientific
study, but especially because the invariable order assumed by its hues
is the only stable hint which Nature affords us in her infinite color
play.

(19) All our color sensations are included in the color solid. None are
left out by its scales of hue, value, and chroma. Indeed, the
imagination is led to conceive and locate still purer colors than any we
now possess. Such increased degrees of color sensation can be named, and
clearly conveyed by symbols to another person as soon as the system is
comprehended.

APPENDIX TO CHAPTER I.

+Misnomers for Color.+

The Century Dictionary helps an intelligent study of color by its clear
definitions and cross-references to HUE, VALUE, and CHROMA,--leaving no
excuse for those who would confuse these three qualities or treat a
degree of any quality as the quality itself.

Obscure statements were frequent in text-books before these new
definitions appeared. Thus the term "shad