tral" of our
_nervous system_? Whatever you do to build up and help the other parts
of the body will help your brain to _feel_ and _think_ and _remember_;
and will help your muscles and nerves to answer promptly and truly
whatever the message may be. Plenty of good food, plenty of sleep and
fresh air, plenty of play, will keep your nerves and brain healthy and
growing.

"ABSENT TO-DAY?"

I. KEEPING WELL

How many times have you been absent this term? No oftener than you
were obliged to be, I am sure; for it's almost as bad as being "put in
Coventry" to come back and hear about the good time the rest of the
class have been having, and feel that you "weren't in it." Of course,
sometimes, when you are not well, you have to be absent; it is best
that you should be. But it is better still to know how to keep well,
so you won't have to be absent, and won't have to miss any good times
in work or play all your life.

You remember that all the parts of your body are fed and ventilated by
the blood, which is pumped to them from the heart. So long as this
blood is pure and has plenty of oxygen in it, it does good to every
part of the body to which it comes. But the moment that poisons and
dirt and waste begin to pile up in the blood, then the blood that
comes to the different parts of the body may be poisonous to them,
instead of helpful.

Such poisons in the blood are particularly harmful to the nerves and
the brain, because these are among the most delicate and sensitive of
all the structures in the body.

Often we think of the body as a beautiful house. Now a house does not
look very beautiful when it has dust and crumbs on the floor, buckets
of greasy dishwater in the kitchen, and smoke from the furnace in the
air! You could not live in such a place. No, the smoke must go out up
the chimney, the dust and crumbs must be swept away, the dirty water
must be drained off in pipes; the house must be not only cleaned, but
kept clean all the time. This is true of your body, too.

Now Mother Nature sends the smoke from the body out through the lungs,
and the crumbs and solid dirt down and out by means of the food tube.
But the waste water--how does she get rid of that? The waste water,
you remember, is in the blood vessels, mixed with the blood. How does
she get it out of the blood? She sends it through three magic
cleaners, or strainers,--the _skin_, the _liver_, the _kidneys_.

That the skin is a strainer, you alre