15 15.7 8.7 10.3 14.9

Column _A_ contains the filled spaces, columns _B_, _C_, _D_,
_E_ the open spaces that were judged equal. In _B_ the block
was moved with the finger, and in _C_ against the finger as it
traversed the filled space, and in _D_ and _E_ the block was
moved with and against the finger respectively as it passed
over the open space. The block was always moved approximately
one-half the distance of the filled space.


I have given some of the results for one subject in Table XII. These
results show at a glance how potent a factor the time element is. The
quantity of tactual sensations received by the finger-tip enters into
the judgment of space to no appreciable extent. With one subject,
after he had passed his finger over a filled space of 10 cm. the block
was moved so as almost to keep pace with the finger as it passed over
the open space. In this way the subject was forced to judge a filled
space of 10 cm. equal to only 2 cm. of the open space. And when the
block was moved in the opposite direction he was made to judge a
distance of 10 cm. equal to an open distance of 16 cm.

The criticism may be made on these experiments that the subject has
not in reality been obliged to rely entirely upon the time sense, but
that he has equated the two spaces as the basis of equivalent muscle
or joint sensation, which might be considered independent of the
sensations which yield the notion of time. I made some experiments,
however, to prove that this criticism would not be well founded. By
arranging the apparatus so that the finger-tip could be held
stationary, and the block with the open and filled spaces moved back