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Common Science 



FIG. 71. The reading glass is a lens which focuses the light from the candle 

 flame and forms an image. 



the light from the point will get all mixed up with the 

 light from the base, as shown in Figure 70. Naturally, 

 if the light from the point of the candle flame is mixed 

 up with the light from the base and the beams are all 

 crisscross, you will not get a clear picture of the flame. 



Experiment 47. Fasten a piece of paper against a wall 

 and place a lighted candle about 4 feet in front of it. Look 

 at the paper. Is there any picture of the candle flame on 

 it? Now hold a magnifying glass (reading glass) near the 

 candle, between the canolle and the paper, so that the light 

 will shine through the lens on to the paper. (The magnify- 

 ing glass is a lens.) Move the lens slowly toward the paper 

 until you get a clear picture of the candle flame. Is it right 

 side up or upside down? 



The lens has brought the light from the candle flame 

 to a focus; all the light that goes through the lens from 

 one point of the flame has been brought together at 



