Page:Popular Science Monthly Volume 41.djvu/659

 device in a slanting position, and fixing the record-plate upon the wall. The main characteristic of such a record is the sinking of the arm from fatigue; the movement is rapid and coarse (I of Fig. 10). If the attention be directed to the front, we obtain a resultant of the two tendencies, as is shown in the diagonal line of Fig. 9. Fig. 10 illustrates an interesting point similar to that illustrated in Fig. 3. When the attention is directed downward, the hand falls rapidly, I; but when the attention is directed upward, very little movement at all takes place—the tendency to move toward the object of attention constantly counteracting the tendency for the arm to fall. While we have not been altogether successful in recording by these involuntary movements the various powers of different sense-impressions to hold the attention, the few successful results are especially interesting. In Fig. 11 the outline I is the movement of the hand during the thirty-five seconds that the subject was counting the strokes of a metronome; the outline II is the movement while counting for twenty-five seconds the oscillations of a pendulum. The latter movement is much more extensive than the former; the visual holds the attention better than the auditory impression. The subject of this record is a noted American novelist, and his description of his own mental processes entirely corresponds with this result. He is a good visualizer, and is eye-minded in every respect.

We turn to Fig. 12. The subject was asked to call the names of a series of small patches of colored papers hanging upon the wall in front of him. He did this with some uncertainty for