throwing snowballs, let him drink when he is thirsty, and go on with his game after drinking, and you need not be afraid of any ill effects.  And if any other exercise makes him perspire let him drink cold water even in winter provided he is thirsty.  Only take care to take him to get the water some little distance away.  In such cold as I am supposing, he would have cooled down sufficiently when he got there to be able to drink without danger.  Above all, take care to conceal these precautions from him.  I would rather he were ill now and then, than always thinking about his health.

Since children take such violent exercise they need a great deal of sleep.  The one makes up for the other, and this shows that both are necessary.  Night is the time set apart by nature for rest.  It is an established fact that sleep is quieter and calmer when the sun is below the horizon, and that our senses are less calm when the air is warmed by the rays of the sun.  So it is certainly the healthiest plan to rise with the sun and go to bed with the sun.  Hence in our country man and all the other animals with him want more sleep in winter than in summer.  But town life is so complex, so unnatural, so subject to chances and changes, that it is not wise to accustom a man to such uniformity that he cannot do without it.  No doubt he must submit to rules; but the chief rule is this—­be able to break the rule if necessary.  So do not be so foolish as to soften your pupil by letting him always sleep his sleep out.  Leave him at first to the law of nature without any hindrance, but never forget that under our conditions he must rise above this law; he must be able to go to bed late and rise early, be awakened suddenly, or sit up all night without ill effects.  Begin early and proceed gently, a step at a time, and the constitution adapts itself to the very conditions which would destroy it if they were imposed for the first time on the grown man.

In the next place he must be accustomed to sleep in an uncomfortable bed, which is the best way to find no bed uncomfortable.  Speaking generally, a hard life, when once we have become used to it, increases our pleasant experiences; an easy life prepares the way for innumerable unpleasant experiences.  Those who are too tenderly nurtured can only sleep on down; those who are used to sleep on bare boards can find them anywhere.  There is no such thing as a hard bed for the man who falls asleep at once.

The body is, so to speak, melted and dissolved in a soft bed where one sinks into feathers and eider-down.  The reins when too warmly covered become inflamed.  Stone and other diseases are often due to this, and it invariably produces a delicate constitution, which is the seed-ground of every ailment.