There will be one advantage of our plays in the dark. But if you mean them to be successful, you must make them as gay as possible. Darkness is of all things the most gloomy; so do not shut your child up in a dungeon. When he goes into the dark make him laugh; when he leaves it make him laugh again; and all the time he is there, let the thought of what he is enjoying, and what he will find there when he returns, protect him from the shadowy terrors which might otherwise inhabit it. I have heard some propose to teach children not to be afraid at night, by surprising them. This is a bad plan, and its effect is contrary to the one sought: it only makes them more timid than before. Neither reason nor habit can accustom us to a present danger, the nature and extent of which we do not know, nor can they lessen our dread of unexpected things however often we meet with them. But how can we guard our pupil against such accidents? I think the following is the best plan. I will tell my Émile, "If any one attacks you at night, you are justified in defending yourself; for your assailant gives you no notice whether he means to hurt you or only to frighten you. As he has taken you at a disadvantage, seize him boldly, no matter what he may seem to be. Hold him fast, and if he offers any resistance, hit him hard and often. Whatever he may say or do, never let go until you know exactly who he is. The explanation will probably show you that there is nothing to be afraid of; and if you treat a practical joker in this way, he will not be likely to try the same thing again." Although, of all our senses, touch is the one most constantly used, still, as I have said, its conclusions are the most rude and imperfect. This is because it is always used at the same time with sight; and because the eye attains its object sooner than the hand; the mind nearly always decides without appealing to touch. On the other hand, the decisions of touch, just because they are so limited in their range, are the most accurate. For as they extend no farther than our arm's length, they correct the errors of other senses, which deal with distant objects, and scarcely grasp these objects at all, whereas all that the touch perceives it perceives thoroughly. Besides, if to nerve-force we add muscular action, we form a simultaneous impression, and judge of weight and solidity as well as of temperature, size, and shape. Thus touch, which of all our senses best informs us concerning impressions made upon us by external things, is the one oftenest used, and gives us most directly the knowledge necessary to our preservation. The Sense of Sight.