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NEAR SIGHT. 



eye : and (as a bent stick is not so far 

 from end to end as a straight one) so the 

 fishes appear nearer our eye than they 

 really are. 



Q. Why are some persons NEAR-SIGHTED ? 



A. Because the COR'NEA of their eye 

 is so prominent, that the image of distant 

 objects is reflected before it reaches the 

 RET'INA; and, therefore, is not distinctly 

 seen. 



N.B. The cor'nea shields the CRYSTALLINE LENS, 

 and is more or less convex according to the lens which 

 it covers. 



Q. What is meant by the "COR'NEA of the 



EYE?" 



A. All the outside of the visible part 

 of the eye-ball. 



The curve ABC is called 

 the COB'NEA. 



If this curve be too prom- 

 inent (or convex), the eye is 

 near-sighted. 



If too flat (or concave), the 

 eye is far-sighted. 



Q. What is meant by the "RET'INA of the 

 EYE?" 



A. The net-work which lines the 

 back of the eye, is so called. 



