NOTICEABLE INCIDENTS 75 



12. The primary necessity to the development of 

 varied song in species or individual is leisure. One 

 cause of the persistence of the songs of caged birds 

 may be found in this result of their changed 

 condition of life — that they have nothing to 

 do but to sing. The wild bird has always plenty 

 to notice and consider, — the approach of various 

 creatures — men, beasts, hawks, and other birds ; the 

 sounds which these produce, and which signify 

 various degrees of safety, or of peril ; the indications 

 of food in air, or tree, or on the ground ; and, lastly, 

 the state of the atmosphere, and the various weather- 

 signs which all birds observe; — such incidents as 

 these occupy the wakeful hours of the wild bird. 

 But the caged bird — often secluded from all com- 

 munication with his kind (one, perchance, of a 

 gregarious species), without the necessity of seeking 

 food, with a horizon limited perhaps by a smoky 

 garden, perhaps by a dingy window — can take no 

 exercise but in hopping from perch to perch, across 

 and across his cage ; and can hear no call-notes but 

 his own, which he repeats again and again, and, if 

 he has been reared in a cage, his own song, which 

 he seems to utter as much for the sake of such 

 occupation as it affords, as to express by means of 

 it any desire for a mate, or any pleasure in his 



