or other similar article, is a particularly good illustration of the adaptation and specialization of old movements for new purposes. The throwing motion is made countless times before the child throws purposely, and it is not difficult to trace throwing to a number of earlier, fairly distinct hand-movements like shaking, tossing, threshing a newspaper, tossing and shaking toys—which one may observe as early as the eighth month, or earlier in the case of some children. A little later, the child begins to carry his toys to the edge of his crib, letting them drop as if to get rid of them, or possibly to hear them fall: or, if seated in a high-chair, the child will pick up from the table and drop on the floor spoons, dolls, rattles, balls—in fact, anything he can reach. Out of such movements the throwing motion is differentiated and selected. And if there is a ball in the child's collection of playthings, ball throwing in particular is selected, one may suppose, because more happens when a ball is thrown or tossed than when another article, such as a spoon or rattle, is thrown. The ball rolls away giving the child the delight which accompanies the sight of all moving things. So ball throwing soon comes to be a favorite form of play.
My observation of R.'s learning to throw a ball began in the first week of his second year. At that time, before the child had learned to creep, he would sit on the floor and throw a ball as long as any one was willing to get it and return it to him, shouting with delight at every
