It is to be remarked, however, that the ability to keep the suppressed image out of the field increased with practice and that A. and F. had less than half the number of experiments that the rest had.  D., who had but two thirds as many as most of the other subjects and therefore had less practice in suppressing the image, stands yet second in respect to this ability.

If we compare the subjects with regard to first efforts and first absences only, we obtain the following orders: 

According to Ave.  Time req.             According to Ave.  Absence
for first Suppression.             of Image after first Suppression. 
J.        3.59 sec.                     B.       270.44 sec. 
B.        5.79  "                      D.       190.07  "
C.        7.88  "                      F.        86.07  "
I.        9.77  "                      H.        73.27  "
F.       12.67  "                      K.        71.90  "
H.       15.27  "                      I.        53.83  "
K.       21.63  "                      C.        43.08  "
G.       21.88  "                      J.        32.18  "
D.       23.28  "                      G.        20.39  "
A.       28.32  "                      A.        11.29  "

Arranging the groups of images suppressed according to the average times of all suppressions and absences we have these orders: 

Suppression.                       Absences. 
Central Images,  5.41       Marginal Images,  125.12
Upper     "      6.95       Sundry     "       68.78
Left      "      8.60       Left       "       51.26
Right     "      8.94       Lower      "       50.04
Lower     "      9.11       Right      "       43.93
Marginal  "     11.35       Upper      "       32.35
Sundry    "     12.09       Central    "       26.54

SUBJECTIVE.

Most of the subjects imaginatively placed the image to be suppressed behind the screen, in a drawer, in their closed hands, pushed it forward into the remote distance, sliced up, burned up, or pulverized and so destroyed it.  B. and D. ‘thought it away’ directly, without mechanism or device, or got rid of it ‘by a pure act of will.’  Superposition was tried, frequently with success, but at times the under image shone through.  When the objects were colored discs one superposed on the other, the subject spread over the whole surface the color of the image to be retained, but at times this resulted in there being two shades of the upper color, and a yellow above a red changed to an orange.  When red was above yellow, the red appeared more highly illuminated.  Associations with objects of the color of the retained image were found helpful but tended to modify the original color.  Such associations also, at times, by secondary associations brought back the suppressed image.  For example, when thinking of buttercups to enforce a yellow image, the picture of grass surrounding the flowers brought back the suppressed green image.