The notes show, further, that the image of the figure first seen was not only less persistent but relatively less vivid than the other, though the latter was not invariably the case.  One subject had ’an impression that the images were farther apart’ than in the series where the exposure of the two objects was simultaneous, though the distance between the objects was in all cases the same, the time difference being, apparently, translated into spatial terms and added to the spatial difference.  The sort of antagonism which temporal distinctions tend, under certain conditions, to set up between ideas is illustrated by the remark of another subject, who reports that ’the attention was fairly dragged by the respective images.’  And the fact of such antagonism, or incompatibility, is confirmed by the extremely low figure which represents the average time when both images were reported present at the same time.  The two images, separated by processes which the time interval implies, seem to be more entirely incompatible and mutually inhibitory than the images of objects simultaneously perceived.  For not only does the advantage of a few seconds give the fresher image a considerable preponderance in its claim on the attention, but even the earlier image, after it has once caught the attention, usually succeeds in shutting out the other from a simultaneous view.

TABLE X.

1           2           3           4           5      Indiv.  Aver. 
V     H     V     H     V     H     V     H     V     H     V     H
I. 27.5  27    26.5  28    30.5  24.5  27.5  28.5  26    25    27.60 26.60
II. 45    43.5  37    40    35.5  28.5  19    15.5  30.5  30.5  33.40 31.60
III. 19    21     0    10.5  19.5  19     9    15     4.5  16    10.40 16.30
IV. 47.5  39    36    22.5  44.5  41.5  47.5  46    37    36    42.50 37.00
V. 56.5  46.5  42.5  42.5  48    45.5  48.5  48.5  53    52    49.70 47.00
VI. 31.5  28.5  30.5  30.5  22    34.5  34.5  28.5  25    26.5  28.70 29.70
VII. 55    55    55    45.5  38    20    55.5  53.5  56    56    51.90 45.80
VIII. 39.5  47    23.5  23.5  19    18.5  26.5  26.5  26    20.5  26.90 27.20
IX. 26.5  46    38    42.5  41    44    40.5  46.5  35.5  39    36.30 43.60
X. 24.5  25    26    25    25.5  23    23.5  28.5  32.5  20.5  26.40 24.40
XI. 52    52    56.5  54.5  48    49.5  45    47.5  51.5  47.5  50.60 50.20

      38.60 39.14 33.77 33.09 33.77 31.68 34.27 34.95 34.31 33.60 34.94 34.49

   V:  Vertical. H:  Horizontal.

   General average:  Vertical, 34.94 sec.; Horizontal, 34.49 sec.

Series No.  X.—­The objects used in this experiment were straight lines, two strips of granite-gray cardboard, each ten centimeters long and half a centimeter wide, the one being vertical and the other horizontal.  These were pasted on black cards and exposed in alternate positions, each appearing once to the right and once to the left.  The figures in the columns represent in each case the combined result of two such observations.