dance and dance music of the higher cultural strata and that of the basic strata, with special reference to the dance of the sixteenth century, I am doing this, first, because we can see that neither before nor after that century is the interest of the higher strata in the dance and dance music of the lower strata in any way comparable or widespread; and second, because it seems that, in the evolution of dance and dance music, the sixteenth century is really important, for in it one period of evolution ended and another began. This upheaval of evolution was caused, as I see it, especially by the invention of printing musical notes. Music ceased to be disseminated from mouth to mouth or from instrument to instrument; people were able to buy printed music. Moreover, certain fundamental principles began to change. Instead of improvised minstrelsy and of more or less improvised dancing, there was composed and prescribed dance and dance music. Instead of free manipulation with formulas, we find the interpretation of a prescribed form. This was the moment in history when instrumental music began to be "ars musica", and when dance began to be "ball-room dance" or what we call in German Gesellschaftstanz.