object of the experiment. This and the other recognized laboratory
precautions were carefully observed throughout this work. Four
distances were used, 4, 8, 12 and 16 cm. At frequent intervals
throughout the tests the contact was made with only one of the points
instead of four. In this way there came to light again the interesting
fact which we have already seen in the last section, which is of great
significance for my theory--that the end points are located
differently when given alone than when they are presented
simultaneously with the other points. I give a graphic representation
of the results obtained from a large number of judgments in Figs. 4, 5
and 6. These experiments with filled spaces, like the earlier
experiments, were made on the volar side of the forearm beginning near
the wrist. In each distance four points were used, equally distributed
over the space. The shaded curve, as in the previous figures,
represents the results of the attempts to localize the points when all
four were given simultaneously. In the dotted curves, the end points
were given alone. The height of the curve at any place is determined
by the number of times a point was located immediately underneath that
particular part of the curve. In Fig. 4 the curve which was determined
by the localization of the four points when given simultaneously,
shows by its shape how the points appear massed towards the center. In
Fig. 5 the curve _AB_ shows, by its crests at _A_ and _B_, that the
end points tended to free themselves from the rest in the judgments.
But if the distance _AB_ be taken to represent the average of the
judgments upon the filled space 1, 2, 3, 4, it will be seen to be
shorter than what may be regarded as the average of the judgments upon
the corresponding open space, namely, the distance _A'B'_, determined
by the localizations of the end points alone. The comparative
regularity of the curve indicates that the subject was unable to
discriminate among the points of the filling with any degree of