blackened boxes, the fronts of which were covered with a series of
sheets of white tissue-paper, by which the light was decentralized and
reduced in intensity, and of blue glass, by which the yellow quality
of the light was neutralized. Either of these lanterns could be
illuminated at will by the pressure of a button. All other
experimental conditions remained unchanged. The observers were
directed to pay no special regard to these lights, and the reports
show that in almost every case they had no conscious relation to the
judgment. The results are presented in the following table:


TABLE X.

Light Below. Light Above.
Observer. Const.Err. Av.Dev. M.Var. Const.Err. Av.Dev. M.Var.
_C_ (40) +156.37 156.37 19.67 +169.85 169.85 19.22
_D_ (20) + 39.30 43.30 17.95 + 46.65 47.35 15.41
_F_ (30) + 19.47 19.47 8.83 + 58.37 58.37 7.83
_G_ (50) + 66.11 112.76 14.65 +117.86 117.86 13.10
_H_ (30) -147.63 147.63 21.07 -105.30 105.30 30.31
_J_ (20) + 1.90 31.95 22.33 + 44.40 44.40 20.55
Average: + 22.59 85.28 17.42 + 55.30 90.52 17.74


The eye is uniformly attracted toward the light and the location of
the disk correspondingly elevated or depressed. The amount of
displacement which appears is relatively large. It will be found to
vary with the intensity, extent and distance of the illuminated
surfaces introduced. There can be little doubt that the practical
judgments of life are likewise affected by the distribution of light