he waves and the tide in the
ocean without power to direct its own course. He would be but an inert
mass of flesh without sense or intelligence.

THE MIND AT BIRTH.--Yet this is the condition of the babe at birth. It
is born practically blind and deaf, without definite sense of taste or
smell. Born without anything to think about, and no way to get anything
to think about until the senses wake up and furnish some material from
the outside world. Born with all the mechanism of muscle and nerve ready
to perform the countless complex movements of arms and legs and body
which characterize every child, he could not successfully start these
activities without a message from the senses to set them going. At birth
the child probably has only the senses of contact and temperature
present with any degree of clearness; taste soon follows; vision of an
imperfect sort in a few days; hearing about the same time, and smell a
little later. The senses are waking up and beginning their acquaintance
with the outside world.

[Illustration: FIG. 5.--A NEURONE FROM A HUMAN SPINAL CORD. The central
portion represents the cell body. N, the nucleus; P, a pigmented or
colored spot; D, a dendrite, or relatively short fiber,--which branches
freely; A, an axon or long fiber, which branches but little.]

THE WORK OF THE SENSES.--And what a problem the senses have to solve! On
the one hand the great universe of sights and sounds, of tastes and
smells, of contacts and temperatures, and whatever else may belong to
the material world in which we live; and on the other hand the little
shapeless mass of gray and white pulpy matter called the brain,
incapable of sustaining its own shape, shut away in the darkness of a
bony case with no possibility of contact with the outside world, and
possessing no means of communicating with it except through the senses.
And yet this universe of external things must be brought into
communication with the seemingly insignificant but really wonderful
brain, else the mind could never be. Here we discover, then, the two
great factors which first require our study if we would understand the
growth of the mind--_the material world without, and the brain within_.
For it is the action and interaction of these which lie at the bottom of
the mind's development. Let us first look a little more closely at the
brain and the accompanying nervous system.

3. STRUCTURAL ELEMENTS OF THE NERVOUS SYSTEM

It will help in understandin