CH. LV1II.] 



VISUAL JUDGMENTS 



857 



whether, if some one drops a small object, it falls in front of or 

 behind the bar. 



Visual judgments are not always correct; there are a large 

 number of puzzles and toys which depend on visual illusions. One 

 or two of the best known are represented in the accompanying 

 diagrams. 



In fig. 544, A, B, and c are of the same size ; but A looks taller 

 than B, while c appears to cover a less area than either. The sub- 



A B 



D 



FIG. 544. Diagrams to illustrate visual illusions. 



division of a space or line increases its apparent size or length. 

 In fig. 544 D, ab is equal to be. Vertical distances also are usually 

 over-estimated. In fig. 545 the long lines are parallel, though 



Fia. 545. Zollner's lines 



they do not appear so, owing to the influence of the intercrossing 

 lines. 





