A SUMMER VOYAGE 17 



garden birds one may notice the same tendency. I 

 observe a great variety of songs, and even qualities 

 of voice, among the orioles and among the song 

 sparrows. On this trip my ear was especially 

 attracted to some striking and original sparrow 

 songs. At one point I was half afraid I had let 

 pass an opportunity to identify a new warbler, but 

 finally concluded it was a song sparrow. On an- 

 other occasion I used to hear day after day a spar- 

 row that appeared to have some organic defect in 

 its voice : part of its song was scarcely above a whis- 

 per, as if the bird was suffering from a very bad 

 cold. I have heard a bobolink and a hermit thrush 

 with similar defects of voice. I have heard a robin 

 with a part of the whistle of the quail in his song. 

 It was out of time and out of tune, but the robin 

 seemed insensible of the incongruity, and sang as 

 loudly and as joyously as any of his mates. A cat- 

 bird will sometimes show a special genius for mim- 

 icry, and I have known one to suggest very plainly 

 some notes of the bobolink. 



There are numerous long covered bridges span- 

 ning the Delaware, and under some of these I saw 

 the cliff swallow at home, the nests being fastened 

 to the under sides of the timbers, as it were, sus- 

 pended from the ceiling instead of being planted 

 upon the shelving or perpendicular side, as is usual 

 with them. To have laid the foundation, indeed, 

 to have sprung the vault downward and finished it 

 successfully, must have required special engineering 

 skill. I had never before seen or heard of these 



