HIGHEST UNITS WHICH APPEAR.

Value of interval in secs.:   12/12   7/12   5/12   3/12   2/12   1/12
No. of el’s in rhythm group:  2.5     3.0    4.0    7.0    9.0    11.0
Average duration of group:    2.500   1.750  1.666  1.750  1.500   0.917

  SIMPLE UNITS.

No. of els. in simplest group:  2.5    2.3    2.9    3.7    4.7    5.0
Duration of simplest group:     2.50   1.34   1.21   0.92   0.78   0.41

The rate of increase here presented in the number of elements is not sufficiently rapid to counterbalance the acceleration of speed and maintain a constancy in the duration of the group.  The greatest value of this period is cooerdinated with the slowest rate of succession, the lowest with the most rapid.  As the speed increases, the duration of the rhythmic unit is shortened.  Its average duration for all rates here included is 1.680 sec., or, without the first of the series (one-second intervals, at which only two of the observers received the impression of rhythm), 1.516 sec.  These values are not for the simplest combinations, but for the highest synthetical unit which was immediately apprehended in the series of stimulations.  This compounding becomes more pronounced as the rate of succession is accelerated, but even at intervals of 5/12 and 7/12 sec. it is the characteristic mode of apprehension.

The number of elements in the simple groups of which these higher units are composed, and their average duration, are also given in the table.  These likewise show a progressive increase in number, but of a much slower rate than that manifested by the total synthesis of elements.  That is to say, in subjective rhythm as well as in objectively figured series, subordinate rhythmical differences in the material sink out of consciousness less rapidly than the inclusion of fresh elements takes place; in other words, the organic complexity of the rhythmic unit increases with every acceleration in the rate of succession.  The duration of these simple structural groups, as may be inferred, decreases with such acceleration, but at a much more rapid rate than is the case with the total reach of rhythmical apprehension, the value of that unit which appears in connection with the highest speed here included being less than half a second.  The ‘liveliness’ of such rapid measures is thus a resultant of several factors.  It is not a consequence solely of the more rapid rate at which the individual stimuli succeed one another, but depends also on the shortening of the periods of both these rhythmical units and on the progressive divergence of the simple from the complex group.