Ferrero and others have shown that the more intense activities of primitive people tend to be rhythmic and with strongly automatic features. No form of activity is more universal than the dance, which is not only intense but may express chiefly in terms of fundamental movements, stripped of their accessory finish and detail, every important act, vocation, sentiment, or event in the life of man in language so universal and symbolic that music and poetry themselves seem to have arisen out of it. Before it became specialized much labor was cast in rhythmic form and often accompanied by time-marking and even tone to secure the stimulus of concert on both economic and social principles. In the dark background of history there is now much evidence that at some point, play, art, and work were not divorced. They all may have sprung from rhythmic movement which is so deep-seated in biology because it secures most joy of life with least expense. By it Eros of old ordered chaos, and by its judicious use the human soul is cadenced to great efforts toward high ideals. The many work-songs to secure concerted action in lifting, pulling, stepping, the use of flail, lever, saw, ax, hammer, hoe, loom, etc., show that areas and thesis represent flexion and extension, that accent originated in the acme of muscular stress, as well as how rhythm eases work and also makes it social. Most of the old work-canticles are lost, and machines have made work more serial, while rhythms are obscured or imposed from without so as to limit the freedom they used to express. Now all basal, central, or strength movements tend to be oscillatory, automatically repetitive, or rhythmic like savage music, as if the waves of the primeval sea whence we came still beat in them, just as all fine peripheral and late movements tend to be serial, special, vastly complex, end diversified. It is thus natural that during the period of greatest strength increment in muscular development, the rhythmic function of nearly all fundamental movements should be strongly accentuated. At the dawn of this age boys love marching; and, as our returns show, there is a very remarkable rise in the passion for beating time, jigging, double shuffling, rhythmic clapping, etc. The more prominent the factor of repetition the more automatic and the less strenuous is the hard and new effort of constant psychic adjustment and attention. College yells, cheers, rowing, marching, processions, bicycling, running, tug-of-war, calisthenics and class gymnastics with counting, and especially with music, horseback riding, etc., are rhythmic; tennis, baseball and football, basketball, golf, polo, etc., are less rhythmic, but are concerted and intense. These latter emphasise the conflict factor, best brought out in fencing, boxing, and wrestling, and lay more stress on the psychic elements of attention and skill. The effect of musical accompaniment, which the Swedish system wrongly rejects, is to