Page:Popular Science Monthly Volume 42.djvu/38

28 of hanging listlessly down (Fig. 5). As the interest increases still further the body is bent forward at an angle and the hand is very probably placed firmly on the thigh (Fig. 6). If he becomes excited in the heat of argument, the body is bent forward at a somewhat acute angle and the hand is stretched out in front and somewhat upward, as if to help the words which flow from his lips to drive the thoughts which are rapidly evolved from his brain into his opponent's mind (Fig. 7). In this position the flow of blood through the arterial system onward to the brain as well as its return backward through the veins seems to be particularly easy (Fig. 8).

This position is not only assumed during the heat of argument whether the speaker be sitting or standing, but when one is led to assume it unconsciously it seems to give rise to a rapid and sometimes almost uncontrollable flow of ideas. Thus it occasionally becomes a cause of remorse to devout souls, who during the attempt to pray in church in this attitude are sadly distracted by crowds of ideas which at once disappear on the assumption of an easy sitting posture. The circulation in the cerebral vessels and the current of ideas in the brain are very delicate things and may be modified by very slight causes; thus, an attitude with the head drooping slightly more than that indicated in Fig. 6, and with the chin supported upon the hand, is the one frequently assumed in deep thought, with concentration of ideas upon a single subject, and no desire for immediate expression (Fig. 9). The touch of



the hand upon the head seems to have a directing power over the thoughts which one would formerly have been inclined to deny, but such experiments as those of Tesla and Crookes with electric currents of very high tension give a visible illustration of phenomena previously unknown and seemingly incredible. For in these experiments a person who has put himself into the electric field renders vacuum tubes containing various substances fluorescent, and fills them with a glow of colored light by simply