196 The Bluebird 



their enemies, of which the house wrens, and especially 

 the English sparrows, are chief. However, owing to 

 the continuous warfare waged against them by these 

 pugnacious foes, the bluebirds are, year by year, 

 becoming less numerous about our dwellings. 



In my bird note book I find a sketch of the blue- 

 bird families that have, for several years in succession, 

 occupied my "bird-box." This artificial home con- 

 sisted of a hollow limb, about twenty inches long 

 and eight in diameter, closed at top and bottom, and 

 having an entrance for the birds on one side, while 

 on another side was a door, through which the nest 

 and its contents could be inspected. In the wall 

 opposite to the bird's entrance a microphone was 

 arranged, and a line joined it to a telephone re- 

 ceiver in the house. This unique " bird-box" was 

 located about twelve feet above the ground and made 

 fast to the body of a tree that stood in the rear of the 

 house. 



I did not expect to obtain results that could any 

 more be turned into words than could the music of 

 the veery or the murmuring of a mountain stream; 

 but I wanted to hear the notes of the old birds and 

 young, when undisturbed by man, and this was the 

 only method known to me of accomplishing the de- 

 sired end. 



