No medicine of this sort should ever be taken unless prescribed by a physician.
SUMMARY.
1.

In order to be well and useful we must keep the brain and nerves healthy.
2.

To keep the brain healthy we need plenty of pure air to breathe; proper exercise of the brain by study; sufficient exercise of the muscles in play and work; plenty of good food to make pure blood; a proper amount of rest and sleep.
3.

There are several things we ought not to do.

We should not read or study too much.