PHYSIOLOGICAL PARADOXES. 



definitely illuminated wall, sees there such 

 distinct objects that it unconsciously focuses 

 the wall by modifying its lens. But in this 

 matter the two eyes cannot act separately, so 

 the right eye is automatically set at a long 

 focus, too. Consequently, anything quite near, 

 such as the palm of the right hand, is very 

 hazily and indistinctly seen, and the image 

 of it is easily neglected in comparison with the 

 brilliant scene offered to the other eye by the 

 portion of wall which is in view. Outside this 

 limited view the vision of the left eye is limited 

 by the circle of the paper roll. Not so with 

 the right eye. It is free to see the palm of 

 the hand indistinctly, because it is out of 

 focus, but quite perceptibly. 



Thus we get the following combination : 

 The left eye sees distinctly the portion of 

 wall enclosed within the ring of the paper 

 roll, in comparison with which the right eye 

 neglects the corresponding part of its own 

 field of vision, including part of the palm, which 

 is out of focus and indistinct. Outside this 

 part of the field of vision, the right eye sees 

 the rest of the palm indistinctly, because out 

 of focus, yet positively. In comparison with 

 this, the left eye neglects the corresponding 

 part of its field, the interior of the paper roll, 

 which is equally out of focus, much darker, and 

 in strong contrast with the well illuminated 

 and well focused image coming through it. 



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