ck with the other hand. This whole complex movement is of course
more difficult and demands a somewhat longer period of learning, but
as soon as it is learned an extreme saving of psychophysical energy
and a correspondingly great economic gain is secured. The newly
trained masons are not even allowed to gather up with the trowel any
mortar which falls to the floor, because it was found that the loss of
mortar is economically less important than the waste of psychophysical
energy in bending down.

Whoever has once schooled his eye to observe the limitless waste of
human motions and psychophysical efforts in social life has really no
difficulty in perceiving all this at every step. This ability to
recognize possible savings of impulse may be brought to a certain
virtuosity. Gilbreth, one of the leaders of the new movement, seems to
be such a virtuoso. When he was in London, there was pointed out to
him in the Japanese British Exhibition a young girl who worked so
quickly that there at least he would find a rhythm of finger movement
which could not any further be improved. In an exhibition booth the
woman attached advertisement labels to boxes with phenomenal rapidity.
Gilbreth watched her for a little while and found that she was able
to manage 24 boxes in 40 seconds. Then he told the young girl that she
was doing it wrongly, and that she ought to try a new way which he
showed her. At the first attempt, she disposed of 24 boxes in 26
seconds and at the second trial in 20 seconds. She did not have to
make more effort for it, but simply had fewer movements to make. If
such economic gain can be secured with little exertion in the simplest
processes, it cannot be surprising that in the case of more complex
and more advanced technical work which involves highly skilled labor,
a careful psychophysical study of motions must bring far-reaching
economic improvements.

Yet the more important steps will have to be guided by special
experimental investigations, and here the psychological laboratory
must undertake the elaboration of the details. Only the systematic
experiment can determine what impulses can be released at the least
expense of energy and with the greatest exactitude of the motor
effect. Investigations on the psychophysics of movement and the
influences which lead toward making the movement too large or too
small have played an important role in the psychological laboratories
for several decades. It was recognized ear