Rhythm.         1st Interval.      2d Interval.      3d Interval. 
Dactylic,       1.000 :  1.231     1.000 :  1.000     1.000 :  1.066
Amphibrachic,   1.000 :  1.045     1.000 :  1.000     1.000 :  1.054
Anapaestic,      1.000 :  1.050     1.000 :  1.000     1.000 :  1.146

An analysis of the factors of accentual stress and of position in the rhythmical group in isolation from each other, confirms the assumptions already made as to their influence in defining the form of the rhythmic unit.  Table XLIV. exhibits the series of temporal changes taking place in accented and unaccented intervals, respectively, for the three forms combined, and therefore independent of position in the group.

TABLE XLIV.

  Interval.  I II III IV V VI VII VIII IX X
  Accented. 1.000 1.064 1.064 1.064 1.064 1.094 1.094 1.064 1.094 1.129
  Unaccented, 1.000 1.000 1.000 1.080 1.040 1.040 1.040 1.040 1.040 1.040

Similarly, in Table XLV. are given the proportional values of the series of intervals in order of their position in the group and independent of accentual stress: 

TABLE XLV.

  Interval.  I II III IV V VI VII VIII IX X
  First, 1.000 1.043 1.087 1.043 1.087 1.043 1.043 1.121 1.043 1.121
  Second, 1.000 1.000 1.000 1.043 1.000 0.956 1.000 0.956 1.000 0.956
  Third, 1.000 1.028 1.028 1.055 1.028 1.083 1.083 1.083 1.083 1.083

The former table makes clear the predominance of the increase in the accented element over the average of all unaccented elements of the series; the latter shows the independence of increase in the initial and final, and of decrease in the median interval, of any relation to the position of the accentual stress.  Both the intensive accentuation and the demarcation of successive groups thus appear to be factors of definition in the rhythmic unit.  Those types which are either marked by a more forcible accent or separated by longer pauses are more distinctly apprehended and more easily held together than those in which the accent is weaker or the pause relatively less.  It would follow that the general set of changes which these series of reactions present are factors of a process of definition in the rhythmical treatment of the tapping, and are not due to any progressive change in the elementary time relations of the series.

The figures for measures of four beats are incomplete.  They show an increase in the average duration of the group from first to last of the series in three out of the four forms, namely, those having initial, secondary and final stress.

Of the relative amounts contributed by the several elements to the total progressive variation of the measures in the first form, the least marks those intervals which follow unaccented beats, the greatest those which follow accented beats; among the latter, that shows the greater increase which receives the primary accent, that on which falls the secondary, subconscious accent shows the less; and of the two subgroups which contain these accents that in which the major accent occurs contributes much more largely to the progressive change than does that which contains the minor.