All muscular action being stimulated by rhythm, in its simple form or in its more developed form as music, rhythm is a stimulant to work. It has even been argued by Bücher and by Wundt[88] that human song had its chief or exclusive origin in rhythmical vocal accompaniments to systematized work. This view cannot, however, be maintained; systematized work can scarcely be said to exist, even to-day, among most very primitive races; it is much more probable that rhythmical song arose at a period antecedent to the origin of systematized work, in the primitive military, religious, and erotic dances, such as exist in a highly developed degree among the Australians and other savage races who have not evolved co-ordinated systematic labor. There can, however, be no doubt that as soon as systematic work appears the importance of vocal rhythm in stimulating its energy is at once everywhere recognized. Bücher has brought together innumerable examples of this association, and in the march music of soldiers and the heaving and hoisting songs of sailors we have instances that have universally persisted into civilization, although in civilization the rhythmical stimulation of work, physiologically sound as is its basis, tends to die out. Even in the laboratory the influence of simple rhythm in increasing the output of work may be demonstrated; and Féré found with the ergograph that a rhythmical grouping of the movements caused an increase of energy which often more than compensated the loss of time caused by the rhythm.[89]