1 46 Summer Studies of Birds and Books CHAP. 



touch with his mate in this sweet and tender utter- 

 ance. And indeed in my opinion song may be 

 made to serve any useful purpose, according to the 

 conditions in which a bird finds itself. It may even 

 be an expression of anger at some intrusion or 

 calamity. It is well known that you may make a 

 Sedge Warbler sing by poking a stick or throwing a 

 stone into the bush in which he happens to be. I 

 have even known this bird sing vociferously its 

 regular song, though somewhat loudly and harshly, 

 while one of its young brood was being killed close 

 by; for, unknown to me, my dog had seized this 

 tender fledgling, and it was not till I discovered this 

 that I discerned the meaning of the song. I have 

 some reason to think that the Nightingale's song, 

 which is of the same highly emotional type, is also 

 sometimes used in this way ; for Mr. Playne tells me 

 that he has known a Nightingale sing loudly in a 

 tree overhead while he was examining its nest in 

 the undergrowth below. Again, while staying at a 

 house near Newbury, I was taken by my host to see 

 a Wren's nest in the thatched roof of a summer- 

 house, and was told that I should hear the cock bird 

 sing immediately after every visit to the young with 

 food. We sat some time in the arbour, and I found 

 the account perfectly accurate. The female fed her 

 young silently ; but no sooner had the male left the 

 nest than he uttered a distinct song, a somewhat 



