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Our Surroundings 



tin. In making mirrors, the thickness of the glass must be uni- 

 form or the image will be distorted. 



When one looks into a mirror his image seems to be just as 

 far behind the mirror as he is in front of it. The image is also 

 reversed. This is shown by standing in front of a mirror and 



Great Northern Railway. 



REFLECTIONS IN NATURE'S MIRROR 



raising the right hand. Notice which hand the image raises. The 

 same change of image may be shown by trying to read a book 

 by observing its image in a mirror. 



When several rays of light are reflected from a mirror, they 

 leave it bearing the same relation to one another that they had 

 before coming in contact with it. If they were moving parallel 

 to one another before striking the reflecting surface, they remain 

 parallel to one another after leaving it. If they were coming 

 together as they approached the mirror they continue approaching 

 one another after they leave it. If they were drawing farther 

 apart when they struck the mirror, they continue to separate. 



Curved Mirrors. All mirrors do not have plane, or flat, sur- 

 faces. Mirrors for special uses are made with their surfaces 

 curved in many different ways. Those in most common use are 



