64 CITIZEN BIRD 



the morning this life flame of ours, that is called 

 vitality, is very low, like a lire that has burned down, 

 and if we go out in the damp air and breathe the mists 

 that rise from tlie ground our vitality has not strength 

 to resist them. But if we put fresh fuel on our inward 

 fire by eating something before we go out, then that 

 bad little mischief-maker, which we call malaria, has 

 harder work to creep into us." 



" How funny ! May I call Rap to tell him ? Rap ! 

 Rap ! come in and have milk and something to eat, to 

 make your inside fire burn up chills and fever ! " 



Rap thought at first tliat Nat must be craz}^ but 

 very soon understood what the Doctor meant, and was 

 overjoyed at the prospect of having him join the expe- 

 dition. 



" Dodo will cry when she wakes up and knows where 

 we have gone," said Nat, who had been much more 

 kind and thoughtful of his sister since coming to the 

 Farm. But kindness is very catching, and at the Farm 

 everybody w^as kind, from the House People to the 

 big gray horses in the barn, Avhich let the chickens 

 pick up oats from l)etween their powerful hoofs, with- 

 out ever frightening them by moving. 



" It is too long a walk for little sister, but you must 

 remember everything that you see and hear, and tell 

 her about it. Don't forget the field-glass," said the 

 Doctor, following the boys along the road where tele- 

 graph wires made bird-perches between the high poles. 



" You said a lot of birds came last night," said Nat 

 to Rap ; "• but how do you know that they came last 

 night and where did they come from ? " 



" I know they came last night because they w^ere not 



