44 KNIGHT DUNLAP 



foot diagonally back and to the right: the third, in moving the 

 left foot laterally over to the right: the fourth, in advancing the 

 right foot straight forward: the fifth, in advancing the left foot 

 diagonally forward and to the left; and the sixth, in moving the 

 right foot laterally over to the left. At this point the series com- 

 mences again and may be kept up without change for a certain 

 length of tune, when, by moving the right foot backwards instead 

 of forward on a fourth step, the series is reversed, this step forming 

 the first in a new series in which the right foot goes back at one 

 and the left foot forward at four. This series must be modified 

 by turning as the steps are taken, so that the absolute directions 

 of " forward" and "back" are constantly changing, and the rela- 

 tive directions and lengths of steps must be modified in accord- 

 ance with the needs of the floor and the activities of other dancers : 

 but the first thing which has to be done, if waltzing is to be learned 

 quickly and effectively, is to form the two series (direct and re- 

 verse) of six steps each, and make the series mechanically perfect. 

 We may therefore concentrate our exposition on these series. 



In learning the waltz steps, each step is first initiated sepa- 

 rately, as the result of an elaborate system of thought and per- 

 ceptual reflexes. A trained waltzer however initiates only the 

 first step, and if the floor is ample and progress unimpeded, he 

 may give his attention to conversation with his partner for some 

 time, the series of steps taking care of itself. The stages in the 

 progression of the habit up to this point of perfection are material 

 for analysis. 



In figure 1, the lines A' -a, B'-b, C'-c, represent the neural arcs 

 involved in the first, second and third steps respectively of the 

 waltz series. The arcs are of course really multiple, each com- 

 plete transit being made up of transits from many receptors, over 

 many parallel neuron chains, to many effectors (fibers of leg and 

 trunk muscles) ; but the multiple transit and arc in each step may 

 be legitimately represented by a single arc, since the principles 

 involved would apply as well to cases (if such were possible) in 

 which a single receptor discharges to a single effector over a 

 single-track arc. Analytic simplification of this sort is necessary 

 as well as customary. 



