of his engine, turn all the stop-cocks, and shut down the safety-valve, while he still went on all the time putting in coal under the boiler.  The least that he could expect would be a great hissing and fizzling at all the joints of his machine; and it would be only by means of such a degree of looseness in the joints as would allow of the escape of the imprisoned force in this way that could prevent the repression ending in a frightful catastrophe.

Now, nine-tenths of the whispering and playing of children in school, and of the noise, the rudeness, and the petty mischief of children at home, is just this hissing and fizzling of an imprisoned power, and nothing more.

In a word, we must favor and promote, by every means in our power, the activity of children, not censure and repress it.  We may endeavor to turn it aside from wrong channels—­that is, to prevent its manifesting itself in ways injurious to them or annoying to others.  We must not, however, attempt to divert it from these channels by damming it up, but by opening other channels that will draw it away in better directions.

2.  In encouraging the activity of children, and in guiding the direction of it in their hours of play, we must not expect to make it available for useful results, other than that of promoting their own physical development and health.  At least, we can do this only in a very limited degree.  Almost all useful results require for their attainment a long continuance of efforts of the same kind—­that is, expenditure of the vital force by the continued action of the same organs.  Now, it is a principle of nature that while the organs of an animal system are in process of formation and growth, they can exercise their power only for a very brief period at a time without exhaustion.  This necessitates on the part of all young animals incessant changes of action, or alternations of action and repose.  A farmer of forty years of age, whose organs are well developed and mature, will chop wood all day without excessive fatigue.  Then, when he comes home at night, he will sit for three hours in the evening upon the settle by his fireside, thinking—­his mind occupied, perhaps, upon the details of the management of his farm, or upon his plans for the following day.  The vital force thus expends itself for many successive hours through his muscles, and then, while his muscles are at rest, it finds its egress for several other hours through the brain.  But in the child the mode of action must change every few minutes.  He is made tired with five minutes’ labor.  He is satisfied with five minutes’ rest.  He will ride his rocking-horse, if alone, a short time, and then he comes to you to ask you to tell him a story.  While listening to the story, his muscles are resting, and the force is spending its strength in working the mechanism of the brain.  If you make your story too long, the brain, in turn, becomes fatigued, and he feels instinctively impelled to divert the vital force again into muscular action.