The Mighty Deep 



white or yellowish-white, one might expect that 

 everything we look upon would appear to us 

 white or yellowish-white. 



But everything does not. And the reason 

 is that a ray of sunlight is really a bundle of 

 lesser rays, each of which has its own colour. 

 If a ray of light is made to pass through a prism, 

 these lesser sub-rays are spread out upon wall 

 or floor, always in the same order, from violet 

 at one end to red at the other end. Licrht 

 is believed to be due to enormous numbers of 

 most minute wavelets ; and for each colour the 

 wavelets have a definite but different size. They 

 are smallest at the violet end, and largest at the 

 red end. 



Now when a ray of sunlight falls upon any- 

 thing — leaf or flower, earth or water — some of 

 the sub-rays are absorbed or taken in, and some 

 are rejected or refused admission. A healthy 

 leaf, for instance, absorbs the red, the yellow, 

 the blue, the violet, and refuses the green, 

 which is therefore thrown back from the leaf- 

 surface to our eyes, making it green to us. A 

 ripe tomato absorbs the yellow and green, the 

 blue and violet, and reflects the red. A lump 

 of blacklead absorbs greedily all the rays, reflect- 

 ing none, and so to our eyes it is black or 



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