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HOW WE USE LIGHT 



What can you say about the light here? Have you any suggestions to offer? 



Farsightedness is a defect in which the eyeball is too 

 short or the lens too thin and the image of near objects 

 is focused behind the retina. This defect is more 

 difficult to detect and is also the cause of many head- 

 aches. Properly shaped lenses will remedy both 

 nearsightedness and farsightedness by bending the 

 light rays so that they focus properly by means of 

 refraction. 



Care of the Eyes. Some good rules for care of the eyes 

 are these : 



1. Avoid direct glare or reflection from paper, books, 

 or highly polished surfaces. 



2. Do not sit facing strong light. 



3. Do not sit so that your shadow falls on your 

 work. 



4. Do not read or work by a flickering light. 



5. Do not read on trains or motor cars. 



6. Adjust the intensity of light to your needs. Strong 

 light is needed for fine print. 



