28 



THE POPULAR SCIENCE MONTHLY 



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 be- 

 comes 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 on- 

 ward 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 dur- 

 ing 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 al- 

 most 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 



Fig. 7. 



.^nfYVYVYVYW^C 



^vWrwvwv^ 



Fig. 8. — Tracing from the Brain. A, in upright position; B, with head inclined forward. 



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 phe- 

 nomena 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 fluores- 

 cent, and fills them with a glow of colored light by simply wav- 



