74 GOOD HEALTH 



I learn from all this that when the letters are small 

 and the lines near together it is best not to have long 

 lines. In fact, the smaller the letters are the shorter the 

 lines ought to be. Notice the length of the lines on this 

 page. How many words do you find in each line ? 



It is easy to see that if the page you are reading were 

 as wide as a newspaper, if the letters were small, if the 

 lines were packed together closely, and if they stretched 

 across the whole page from one side to the other, it 

 would be hard for the eye to jump back from the end of 

 one line to the beginning of the next. With large letters, 

 therefore, each line may be much longer than when the 

 letters are small. 



People who print books usually think of these things. 

 They use white paper and black ink ; they do not crowd the 

 lines together ; they leave a good margin around the edge 

 of the page ; they do everything that will help the eyes and 

 save them from doing hard work when they use books. 



If you wish to make a little examination of your own 

 eyes you may use the newspaper again in a different 

 way. Pin it to the side of the room and step as far from 

 it as will let you see the large letters easily. Read with 

 both eyes first. Now read with one eye at a time. While 

 you are using one eye leave the other one wide open, but 

 cover it with something black or with your hand. 



If you find that you can read better with one eye than 

 you can with the other, there is some trouble and your 



