PREPARING FOR THE JOURNEY 



has disappeared. It was fuel for the engine. 



Even the birds that travel overland, where 

 food is plentiful, take some fuel with them. I 

 have noticed when collecting and preserving 

 specimens of birds in South America in the 

 spring for the American Museum, that all the 

 North American birds which were about to start 

 on the long journey to their summer homes were 

 very fat, while all the native birds, which were 

 getting ready to nest, were practically without 

 fat. 



Still, there they were, living together; eating, 

 probably, much the same kind of food. Why 

 this food should make one bird fat and the other 

 thin it is difficult to say. But we may be sure 

 that in each case it was preparing the bird for 

 the work it had to do. 



SUGGESTIONS FOR STUDY 



Compare a bird with an aeroplane. How does 

 a bird's flight differ from that of an aeroplane? 

 Mention some of the birds you know and describe 

 the shape and relative size of their wings. Are they 

 long and pointed; short and rounded; large or 



