A WATER-TELESCOPE. 



HAT is a water-telescope?" 

 I suppose this question 

 will be the first one to be 

 asked by every boy 



^ or girl who begins to 



read this chapter. It 

 is a proper question, 

 too, for it is always well to find out at the begin- 

 ning what we are to read about. 



Well, then, I will reply that it is not a telescope 

 at all, if we use that word in its strict meaning. 

 A real telescope is an in- 

 strument which helps to 

 see distant objects by mak- 

 ing them seem nearer. The 

 largest telescopes are used 

 by astronomers, who wish 

 to study the moon or the 

 stars. 



Many common telescopes 

 are called spy-glasses, and 

 are used in looking at dis- 



175 



REFERENCE TOPICS. 



Structure of telescopes. 



Great telescopes of the 

 world. 



The Increase of knowl- 

 edge by means of the 

 telescope. 



The sea as a great aqua- 

 rium. 



Tlie abundance of sea- 

 life. 



Peai'l-oystersand pearls. 



The beauties of the sea. 



