114 THE DISCOVERY OF THE CHILD be conceived of as a means to moderate or worse to inhibit move- ment; it should only function as an aid to a better expenditure of energy, whilst allowing it to develop normally. In nature children possess a guide which leads them to modify their way of moving about; this does not need to be demonstrated. The infant's movements are ceaseless and unco-ordinated like those of a puppet; the child of three is always on the move, often throw- ing himself on the ground, running about and touching everything; the child of nine walks and moves about no longer feeling the need to stretch himself on the ground or to lay hold of everything with which he comes in contact. These modifications develop by themselves, independently of any educational influence. They are associated with an external transformation of the proportions of the body, between the length of the trunk and that of the lower limbs. In the new-born child the length of the, trunk from the top of the head to the hollow of the groin is equal to 68 % of the total length of the body; this means that the legs represent 32% of the length. On the other hand, in the adult man, bust and legs are about equal in length. The change in these proportions forms part of growth. When the child enters our schools at three years of age, his legs correspond to 38% of his height; and then they grow, relatively to the trunk, until they exceed by a great deal the proportions in the adult; already at seven years of age the legs are 75% of the height. It is known that after puberty it is the trunk which grows mainly, until it attains the usual adult pro- portions. It is worth while to consider such an elementary detail of growth in order that we may understand that children's needs in respect to movement must vary, and th9.t we must observe them as they move about spontaneously if we are to be able to help them to grow up to their fullest possible measure. It is enough to point out some fundamental characteristics. Children with their short legs are making great efforts to establish perfect balance, and with a little run they mask the difficulty of simply .walking, whilst they feel the need for resting themselves by extend- ing their trunk on the ground and raising their legs in the air.