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THE POPULAR SCIENCE MONTHLY 



mind, and it is essential to determine in what measure each ap- 

 pears in the general result. 



If you hold out your arm nearly on a level with the shoulders 

 and in line with them, you perceive at once that movements of 



the hand to the front are 

 much more readily made 

 than to the rear, and 

 movements toward the 

 body more readily than 

 those away from the 

 body ; the tendency of 

 the hand is to move along 

 a circle of which the 

 shoulder is the center. 

 What we require is a 

 position in which move- 

 ments in any direction 

 are as readily made as in 

 any other ; and this may 

 be approximated, though only approximated, by holding the hand 

 at an angle of about 45 with the line joining the shoulders, and 

 with the elbow bent at an angle of about 120; this position* is 



Fig. 4. -> Counting Metronome. Kiglit band holds 

 pencil, left hand holds record ; time of each, 90 sec- 

 onds. Facing w-. Upper line, standing ; lower 

 line, sitting. 



Fig. 5. Thinking of a Building. Fac- Fig. 6. Counting Metronome. Ri^ht hand 



ing J ; standing. Right hand holds pen- 

 cil, left hand holds record ; time of each, 

 60 seconds. I, J ; II, J ; shows respi- 

 ration. 



holds pencil, left hand holds record. From 

 A to B, J ; from B to C, *- ; from C to D, 

 J ; from D to E, ^-w ; standing ; each part, 

 45 seconds. 



recommended for the normal tests. The usual result is a move- 

 ment toward the object of attention ; but when that is to the rear, 

 this tendency is sometimes outweighed by the natural tendency 



* In one series we were able to measure the extent of movements in various directions, 

 and found half again as much movement toward the front as toward the rear, and a third 

 again as much toward as away from the body. 



