se. This seems to show that "dextrality" is not derived
from the experience of the individual in using either hand
predominantly for reaching, grasping, holding, etc., within the
easiest range of that hand. The right hand intruded regularly upon the
domain of the left.

Proceeding upon the clew thus obtained, a clew which seems to suggest
that the hand preference is influenced by the stimulus to the eye, I
introduced hand observations into a series of experiments already
mentioned above on the same child's perception of the different
colours; thinking that the colour stimulus which represented the
strongest inducement to the child to reach might have the same effect
in determining the use of the right hand as the increased distance in
the experiments already described. This inference is proved to be
correct by the results.

It should be added that in all cases in which both hands were used
together, each hand was called out with evident independence of the
other, both about the same time, and both carried energetically to the
goal. In many other cases in which either right or left hand is given
in the results, the other hand also moved, but in a subordinate and
aimless way. There was a very marked difference between the use of
both hands in some cases, and of one hand followed by, or accompanied
by, the other in other cases. It was very rare that the second hand
did not thus follow or accompany the first; and this was extremely
marked in the violent reaching for which the right hand was mainly
used. This movement was almost invariably accompanied by an objectless
and fruitless symmetrical movement of the other hand.

The results of the entire series of experiments on the use of the
hands may be stated as follows, mainly in the words in which they were
summarily reported some time ago:

1. I found no continued preference for either hand as long as there
were no violent muscular exertions made (based on 2,187 systematic
experiments in cases of free movement of hands near the body--i. e.,
right hand, 577 cases; left hand, 568 cases--a difference of 9 cases;
both hands, 1,042 cases; the difference of 9 cases being too slight to
have any meaning); the period covered being from the child's sixth to
her tenth month inclusive.

2. Under the same conditions, the tendency to use both hands together
was about double the tendency to use either (seen from the number of
cases of the use of both hands in the figures given above)