value, numeral below for chroma.

_Sequences of color._

Two scales united, as hue and value, or chroma and value.
Three scales united,--each step a change of hue, value, and chroma.

_Balance of color._

Opposites of equal value and chroma (R 5/5 and BG 5/5).
Opposites of equal value and unequal chroma (R 5/9 and BG 5/3).
Opposites unequal both in value and chroma (R 7/3 and BG 3/7).
AREA as an element of balance.

+HARMONY of color.+

(50) _Selection of colors_ that give pleasure.

Study of butterfly wings and flowers, recorded by the NOTATION.
Study of painted ornament, rugs, and mosaics, recorded by
the NOTATION.
Personal choice of color PAIRS, balanced by H, V, C, and area.
Personal choice of color TRIADS, balanced by H, V, C, and area.

_Grouping of colors_ to suit some practical use: wall papers, rugs,
book covers, etc.

Their analysis by the written notation.
Search for principles of harmony, expressed in measured terms.

+A definite plan of color study, with freedom as to details of
presentation.[16]+

[Footnote 16: See Color Study assigned to each grade, in
Part II.]

(51) Having memorized these broad divisions of the study, a clever
teacher will introduce many a detail, to meet the mood of the class, or
correlate this subject with other studies, without for a moment losing
the thread of thought or befogging the presentation. But to range at
random in the immense field of color sensations, without plan or
definite aim in view, only courts fatigue of the retina and a chaotic
state of mind.

(52) The same broad principles which govern the presentation of other
ideas apply with equal force in this study. A little, well apprehended,
is better than a mass of undigested facts. If the child is led to
discover, or at least to think he is discovering, new things about
color, the mind will be kept alert and seek out novel illustrations at
every step. Now and then a pupil will be found who leads both teacher
and class by _intuitive_ appreciation of color, and it is a subtle
question how far such a nature can be helped or hurt by formal
exercises. But such an exception is rare, and goes to prove that
systematic discipline of the color sense is necessary for most children.

(53) Outdoor nature and indoor surroundings offer endless color
illustrations. Birds, flowers, minerals, and the objects in daily use
take on a new interest