Running down a smooth slope is a diversion which easily tempts even grown people, and boys at least find something like it in their game of snapping the whip, in which game a chain is made with the strongest boy in front. He has the task of moving the whole line in curves, so that the end ones are obliged to run in dizzy haste. In both cases natural forces, coming to the aid of the individual’s own efforts, add to the enjoyment. Overcoming difficulties is prominent in the Hellenic πιτυλίζειν, which it seems consisted in running on the tips of the toes, as well as in the equally ancient ἐκπλεθρίζειν, which was a peculiar varied running, without curves, in a straight line back and forth, the line growing shorter and shorter till a central point was reached, where, as only one step remained, the runner came to a standstill.[180] Hopping and skipping are also to be classed with running plays; the body is suspended in the air for an instant in all these movements, though in hopping and skipping the motion is more vertical. They belong in the same category with the vagaries of locomotion which I have pointed out, and any lively child finds it hard to dispense with them when out for a walk, just as lambs and kids do. In the ordinary skip one foot at a time comes with a slight shoving motion on the ground and gives us the beginning of a galop and the principle of the waltz, while hopping forms the foundation for the polka. This hop on one foot is utilized in many plays, such as the hopscotch already mentioned, and in chasing and fighting games, like “Cock Fight” (German Hahnenkampf), “Fox in his Hole,” etc. In Greece the ἀσκωλιάζειν was a popular game, and Grasberger says that their hopping was the same as ours, and in some games he who accomplished the task with the fewest hops won the prize. In a catching game the contestants hopped on a circular line and attempted to touch one another with the free foot. Finally, the drollest and most popular form of the game, which never failed to excite laughter in all beholders, was the genuine Askoliasmos. A skin well oiled on the outside and filled with air was stepped on by the player, who attempted to stand on it while he went through various dancing and hopping motions. The favourite circus trick of running on a rolling cannon ball is a modern form of this.