learnt that a magnet acts through other bodies, our next business is to construct a bit of apparatus similar to that shown us. A bare table, a shallow bowl placed on it and filled with water, a duck rather better finished than the first, and so on. We often watch the thing and at last we notice that the duck, when at rest, always turns the same way. We follow up this observation; we examine the direction, we find that it is from south to north. Enough! we have found our compass or its equivalent; the study of physics is begun.
There are various regions of the earth, and these regions differ in temperature. The variation is more evident as we approach the poles; all bodies expand with heat and contract with cold; this is best measured in liquids and best of all in spirits; hence the thermometer. The wind strikes the face, then the air is a body, a fluid; we feel it though we cannot see it. I invert a glass in water; the water will not fill it unless you leave a passage for the escape of the air; so air is capable of resistance. Plunge the glass further in the water; the water will encroach on the air-space without filling it entirely; so air yields somewhat to pressure. A ball filled with compressed air bounces better than one filled with anything else; so air is elastic. Raise your arm horizontally from the water when you are lying in your bath; you will feel a terrible weight on it; so air is a heavy body. By establishing an equilibrium between air and other fluids its weight can be measured, hence the barometer, the siphon, the air-gun, and the air-pump. All the laws of statics and hydrostatics are discovered by such rough experiments. For none of these would I take the child into a physical cabinet; I dislike that array of instruments and apparatus. The scientific atmosphere destroys science. Either the child is frightened by these instruments or his attention, which should be fixed on their effects, is distracted by their appearance.
We shall make all our apparatus ourselves, and I would not make it beforehand, but having caught a glimpse of the experiment by chance we mean to invent step by step an instrument for its verification. I would rather our apparatus was somewhat clumsy and imperfect, but our ideas clear as to what the apparatus ought to be, and the results to be obtained by means of it. For my first lesson in statics, instead of fetching a balance, I lay a stick across the back of a chair, I measure the two parts when it is balanced; add equal or unequal weights to either end; by pulling or pushing it as required, I find at last that equilibrium is the result of a reciprocal proportion between the amount of the weights and the length of the levers. Thus my little physicist is ready to rectify a balance before ever he sees one.
Undoubtedly the notions of things thus acquired for oneself are clearer and much more convincing than those acquired from the teaching of others; and not only is our reason not accustomed to a slavish submission to authority, but we develop greater ingenuity in discovering relations, connecting ideas and inventing apparatus, than when we merely accept what is given us and allow our minds to be enfeebled by indifference, like the body of a man whose servants always wait on him, dress him and put on his shoes, whose horse carries him, till he loses the use of his limbs. Boileau used to boast that he had taught Racine the art of rhyming with difficulty. Among the many short cuts to science, we badly need some one to teach us the art of learning with difficulty.
The most obvious advantage of these slow and laborious inquiries is this: the scholar, while engaged in speculative studies, is actively using his body, gaining suppleness of limb, and training his hands to labour so that he will be able to make them useful when he is a man. Too much apparatus, designed to guide us in our experiments and to supplement the exactness of our senses, makes us neglect to use those senses. The theodolite makes it unnecessary to estimate the size of angles; the eye which used to judge distances with much precision, trusts to the chain for its measurements; the steel yard dispenses with the need of judging weight by the hand as I used to do. The more ingenious our apparatus, the coarser and more unskilful are our senses. We surround ourselves with tools and fail to use those with which nature has provided every one of us.
But when we devote to the making of these instruments the skill which did instead of them, when for their construction we use the intelligence which enabled us to dispense with them, this is gain not loss, we add art to nature, we gain ingenuity without loss of skill. If instead of making a child stick to his books I employ him in a workshop, his hands work for the development of his mind. While he fancies himself a workman he is becoming a philosopher. Moreover, this exercise has other advantages of which I shall speak later; and you will see how, through philosophy in sport, one may rise to the real duties of man.
I have said already that purely theoretical science is hardly suitable for children, even for children approaching adolescence; but without going far into theoretical physics, take care that all their experiments are connected together by some chain of reasoning, so that they may follow an orderly sequence in the mind, and may be recalled at need; for it is very difficult to remember isolated facts or arguments, when there is no cue for their recall.
In your inquiry into the laws of nature always begin with the commonest and most conspicuous phenomena, and train your scholar not to accept these phenomena as causes but as facts. I take a stone and pretend to place it in the air; I open my hand, the stone falls. I see Emile watching my action and I say, "Why does this stone fall?"
What child will hesitate over this question? None, not even Emile, unless I have taken great pains to teach him not to answer. Every one will say, "The stone falls because it is heavy." "And what do you mean by heavy?" "That which falls." "So the stone falls because it falls?" Here is a poser for my little philosopher. This is his first lesson in systematic physics, and whether he learns physics or no it is a good lesson in common-sense.
As the child develops in intelligence other important considerations require us to be still more careful in our choice of his occupations. As soon as he has sufficient self-knowledge to understand what constitutes his well-being, as soon as he can grasp such far-reaching relations as to judge what is good for him and what is not, then he is able to discern the difference between work and play, and to consider the latter merely as relaxation. The objects of real utility may be introduced into his studies and may lead him to more prolonged attention than he gave to his games. The ever-recurring law of necessity soon teaches a man to do what he does not like, so as to avert evils which he would dislike still more. Such is the use of foresight, and this foresight, well or ill used, is the source of all the wisdom or the wretchedness of mankind.
Every one desires happiness, but to secure it he must know what happiness is. For the natural man happiness is as simple as his life; it consists in the absence of pain; health, freedom, the necessaries of life are its elements. The happiness of the moral man is another matter, but it does not concern us at present. I cannot repeat too often that it is only objects which can be perceived by the senses which can have any interest for children, especially children whose vanity has not been stimulated nor their minds corrupted by social conventions.
As soon as they foresee their needs before they feel them, their intelligence has made a great step forward, they are beginning to know the value of time. They must then be trained to devote this time to useful purposes, but this usefulness should be such as they can readily perceive and should be within the reach of their age and experience. What concerns the moral order and the customs of society should not yet be given them, for they are not in a condition to understand it. It is folly to expect them to attend to things vaguely described as good for them, when they do not know what this good is, things which they are assured will be to their advantage when they are grown up, though for the present they take no interest in this so-called advantage, which they are unable to understand.
Let the child do nothing because he is told; nothing is good for him but what he recognises as good. When you are always urging him beyond his present understanding, you think you are exercising a foresight which you really lack. To provide him with useless tools which he may never require, you deprive him of man's most useful tool—common-sense. You would have him docile as a child; he will be a credulous dupe when he grows up. You are always saying, "What I ask is for your good, though you cannot understand it. What does it matter to me whether you do it or not; my efforts are entirely on your account." All these fine speeches with which you
