You will then get refreshment and rest.  Your mind, during the evening, will be in a different world from that in which you have moved during the day.  At first this will be difficult.  It will be hard for you, unless your mind is uncommonly well disciplined, to dismiss all your cares; and you will think, each evening, that some peculiar emergency demands your attention just at that time, and that as soon as you have passed the crisis you will confine yourself to what you admit are generally reasonable limits; but if you once allow school, with its perplexities and cares, to get possession of the rest of the day, it will keep possession.  It will intrude itself into all your waking thoughts, and trouble you in your dreams.  You will lose all command of your powers, and, besides cutting off from yourself all hope of general intellectual progress, you will, in fact, destroy your success as a teacher.  Exhaustion, weariness, and anxiety will be your continual portion, and in such a state no business can be successfully prosecuted.

There need be no fear that employers will be dissatisfied if the teacher acts upon this principle.  If he is faithful, and enters with all his heart into the discharge of his duties during six hours, there will be something in the ardor, and alacrity, and spirit with which his duties will be performed which parents and scholars will both be very glad to receive in exchange for the languid, and dull, and heartless toil in which the other method must sooner or later result.

* * * * *

If the teacher, then, will confine himself to such a portion of time as is, in fact, all he can advantageously employ, there will be much left which can be devoted to his own private employment—­more than is usual in the other avocations of life.  In most of these other avocations there is not the same necessity for limiting the hours which a man may devote to his business.  A merchant, for example, may be employed nearly all the day at his counting-room, and so may a mechanic.  A physician may spend all his waking hours in visiting patients, and feel little more than healthy fatigue.  The reason is, that in all these employments, and, in fact, in most of the employments of life, there is so much to diversify, so many little incidents constantly occurring to animate and relieve, and so much bodily exercise, which alternates with and suspends the fatigues of the mind, that the labors may be much longer continued, and with less cessation, and yet the health not suffer.  But the teacher, while engaged in his work, has his mind continually on the stretch.  There is little relief, little respite, and he is almost entirely deprived of bodily exercise.  He must, consequently, limit his hours of attending to his business, or his health will soon sink under labors which Providence never intended the human mind to bear.