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through the lapse of ages the birds have, through experience, 

 learned some of the simple laws of sound. "They know as 

 well as man does that certain notes can be heard at a greater 

 distance than others. This knowledge of one of the properties 

 of sound, simple as it is, is the starting point in the acquirement 

 of mimicry, which is the intermediate stage between ventrilo- 

 quism and the ordinary vocal utterances, including their songs." 



Probably very few birds of any species have arrived at such 

 proficiency in this art, for art it certainly is, as have the chats 

 and some of the wrens, which seem able to throw their voices 

 in any direction. Many individuals of other species are only 

 able to modulate their tones so as to seem distant or near, like 

 the crooning of the loons or piping of certain plovers on the 

 wing, and the cooing of the Carolina doves. 



Bradford Torry, who is a close observer and has a quick ear 

 for bird notes, writes of one of the vireos. "The White-eyed 

 is a singer of astonishing spirit, and his sudden changes from 

 one theme to another are sometimes almost startling. He is a 

 skillful ventriloquist also, and I remember one in particular who 

 outwitted me completely. He was rehearsing a well-known strain, 

 but at the end there came up from the bushes underneath a queru- 

 lous call. At first, I took it for granted that some other bird 

 was in the underbrush, but the note was repeated too many 

 times, and came in too exactly on the beat." 



Several of the sparrows modulate their notes so as to greatly 

 deceive in regard to distance. In riding along country roads 

 how often one looks away into fields to see the vesper sparrow 

 (Poozcetes gr amine us), when it is singing from its perch close by, 

 on a fence stake. The song of the field sparrow (Spizella pusilla) 

 is still more deceiving. One is also often puzzled to locate the 

 notes of the Baltimore oriole (Icteria Baltimore). Both sexes 

 have, to a certain extent, this power to mislead, and what is still 

 more curious, the young birds will often perplex one in regard 

 to their whereabouts. 



Few birds with soft voices can project their notes farther than 

 can the cuckoos, but often in the near presence of man there is 



