f his
senses, and verifying with his hand what he cannot as yet appraise
correctly with his eye, is a great exertion. Hence the little one who
is over-taxed by stimuli, in places where these abound, cries or falls
asleep.

The little child of three years old carries within him a heavy
_chaos_.

He is like a man who has accumulated an immense quantity of books,
piled up without any order, and who asks himself "What shall I do with
them?" When will he be able to arrange them in such fashion as to
enable him to say: "I possess a library"?

By means of our so-called "sensory exercises" we make it possible for
the child to _distinguish_ and to _classify_. Our sensory material, in
fact, analyses and represents the attributes of things: dimensions,
forms, colors, smoothness or roughness of surface, weight,
temperature, flavor, noise, sounds. It is the qualities of the
objects, not the objects themselves which are important; although
these qualities, isolated one from the other, are themselves
represented by objects. For the attributes long, short, thick, thin,
large, small, red, yellow, green, hot, cold, heavy, light, rough,
smooth, scented, noisy, resonant, we have a like number of
corresponding "objects" arranged in graduated series. This gradation
is important for the establishment of order; indeed, the attributes of
the objects differ not only in quality, but also in quantity. They may
be more or less high or more or less low, more or less thick or more
or less thin; the sounds have various tones; the colors have various
degrees of intensity; the shapes may resemble each other in varying
degrees; the states of roughness and smoothness are by no means
absolute.

The material for the education of the senses lends itself to the
purpose of distinguishing between these things. First of all it
enables the child to ascertain the _identity_ of two stimuli by means
of numerous exercises in matching and fitting. Afterwards _difference_
is appreciated when the lessons direct the child's attention to the
external objects of a series: light, dark, long, short.

At last he begins to distinguish the _degrees of the various
attributes_, arranging a series of objects in gradation, such as the
tablets which show the various degrees of intensity of the same
chromatic tone; the bells which produce the notes of an octave, the
objects which represent length in decimal proportions, or thickness in
centimetric proportions, etc.

These e