An important problem relates to the possible correlation of types of involuntary movements with age, sex, temperament, disease, and the like. A few observations upon children are interesting in this respect. They reveal the limited control that children have over their muscles, and their difficulty to fix the attention when and where desired. Their involuntary movements are large, with great fluctuations, and irregularly towards the object of attention. Fig. 25 illustrates some of these points; in thirty-five seconds the child's hand moved by large steps seven inches toward the pendulum, and the entire appearance of the outline is different from those obtained upon adults. [Illustration: FIG. 26.--THINKING OF LETTER O. Pencil held in hand; record on table. I., subject standing; II., subject seated.] Much attention has recently been paid to automatic writing, or the unconscious indication of the _nature_, not merely the _direction_ of one's thoughts, while the attention is elsewhere engaged. I attempted this upon the automatograph by asking the subject to view or think of some letter or geometric figure, and then searching the record for some trace of the letter or figure; but always with a negative result. While unsuccessful in this sense, the records prove of value in furnishing a salient contrast to the experiments in which the attention was fixed in a definite direction. For example, the subject is thinking of the letter O; he does not think of it as in any special place, and the record (Fig. 26) likewise reveals no movement in any one direction. Two records are shown quite similar in significance, and illustrating as well the difference between the movements while standing and while sitting. VI