THE NIGHT FLYERS 



tion some birds which travel only at night. Have 

 you ever heard birds calling at night? When? 

 Where? Were they flying over? Were their calls 

 answered? Where is Bedloe's Island? Who made 

 the Statue of Liberty? By whom was it given to 

 the United States? Have you ever seen bird trav- 

 elers in city parks? Why should they visit them? 

 Do you know of any parks in which feeding stands 

 and baths have been arranged for the entertainment 

 of bird visitors? In order to understand clearly 

 how small a section of the sky can be examined 

 through a telescope which takes only the moon in 

 its field, draw on the blackboard a diagram repre- 

 senting the moon at one end, a telescope at the 

 other. It is, of course, only through the narrowest 

 part of this area, that nearest the telescope, that 

 birds are visible. How many have been seen through 

 a telescope in three hours? At what height can 

 birds fly? Describe the observations of Dr. Stone. 



