warm and close? Do you not feel dull and sleepy and so stupid that you
can hardly study? This is because the brain needs good, pure blood to
enable it to work well. So we must always be careful to have plenty of
pure air to breathe.

~4. We should Exercise the Brain.~--What do we do when we want to
strengthen our muscles? We make them work hard every day, do we not? The
exercise makes them grow large and strong. It is just the same with our
brains. If we study hard and learn our lessons well, then our brains
grow strong, and study becomes easy. But if we only half study, and do
not learn our lessons perfectly, then the study does not do our brains
very much good.

~5. We should Take Muscular Exercise.~--When you get tired of study, an
hour's play, or exercise of some sort, rests you and makes you feel
brighter, so that you can learn more easily. This is because exercise is
necessary to make the blood circulate well. It will then carry out the
worn-out particles and supply the brain and nerves with fresh, pure
blood. So the same exercise which makes our muscles strong makes our
brains healthier also.

~6. We should be Careful of our Diet.~--We ought to eat plenty of good,
simple food, such as milk, fruits, grains, and vegetables. It is not
well for children to eat freely of meat, as it is very stimulating and
likely to excite the brain and make the nerves irritable. Mustard,
pepper, and all hot sauces and spices have a tendency to injure the
brain and nerves.

~7. We should Allow the Brain to Rest at the Proper Time.~--When we are
tired and sleepy we cannot think well, and cannot remember what we learn