way of helping the child to recognize differences in
dimension and to place the objects in correct gradation. After the
lesson which I have described, the teacher scatters the brown prisms,
for instance, on a carpet, says to the child, "Give me the thickest of
all," and lays the object on a table. Then, again, she invites the
child to look for _the thickest_ piece among those scattered on the
floor, and every time the piece chosen is laid in its order on the
table next to the piece previously chosen. In this way the child
accustoms himself always to look either for the _thickest_ or the
_thinnest_ among the rest, and so has a guide to help him to lay the
pieces in gradation.

When there is one dimension only which varies, as in the case of the
rods, the objects are said to be "long" and "short," the varying
dimension being length. When the varying dimension is height, the
objects are said to be "tall" and "short"; when the breadth varies,
they are "broad" and "narrow."

Of these three varieties we offer the child as a fundamental lesson
only that in which the _length_ varies, and we teach the differences
by means of the usual "three periods," and by asking him to select
from the pile at one time always the "longest," at another always the
"shortest."

The child in this way acquires great accuracy in the use of words. One
day the teacher had ruled the blackboard with very fine lines. A child
said, "What small lines!" "They are not small," corrected another;
"they are _thin_."

When the names to be taught are those of colors or of forms, so that
it is not necessary to emphasize contrast between extremes, the
teacher can give more than two names at the same time, as, for
instance, "This is red." "This is blue." "This is yellow." Or, again,
"This is a square." "This is a triangle." "This is a circle." In the
case of a _gradation_, however, the teacher will select (if she is
teaching the colors) the two extremes "dark" and "light," then making
choice always of the "darkest" and the "lightest."

Many of the lessons here described can be seen in the cinematograph
pictures; lessons on touching the plane insets and the surfaces, in
walking on the line, in color memory, in the nomenclature relating to
the cubes and the long rods, in the composition of words, reading,
writing, etc.

By means of these lessons the child comes to know many words very
thoroughly--large, small; thick, thin; long, short; dark, light;
rough, sm