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Common Science 



FIG. 90. Making a rainbow on the wall. 



Color is merely a kind of light. We say that a sweater 

 is red ; really the sweater is not red, but the light that 

 it reflects to our eyes is red. We speak of a piece of red 

 glass, but the glass is not red ; it is the light that it lets 

 pass through it that is red. 



White is not really a color; all colors put together 

 make white. Experiments 50 and 51 will prove this. 



Experiment 50. Hold a prism in the sunlight by the 

 window and make a " rainbow " on the wall. The diagram 



VIOLET 



WHITE 



BLUE 

 GREEN 



FIG. 91. The prism separates the white light into the rainbow colors. 



