Page:Bird-lore Vol 05.djvu/98

 A Hermit Thrush Song 85

the long opening notes I speak with great conﬁdence, for I took down a long series on two occasions and found the pitch unchanged From these observations I determined that the ' Thrush used phrases in the following keys. I heard no others and never

detected any ﬂatting or sharpingt It will he noticed that these keys form ‘ part of the scale of A ﬂat major.

In this, and in fact in the whole song, the approximation to the human scale was striking.

The Hermit‘s song consisted. nine times out of ten, in a regular alternation of low with high phrases. Two in succession on or near the same level he never in my hearing gave, but he would sometimes ascend or descend through a series of three diﬁerent keys. There was no ﬁxed order nor any necessary key relation between successive phrases. I have long lists of such and am certain that the bird uttered his theme in what- ever key suited his fancy, so long as it was not a repetition of the theme just uttered. For example, one series began with a low B ﬂat followed by a high A ﬂat, then a middle F, then an upper B ﬂat, then dropped to low A ﬂat, soared up two octaves to high A ﬂat, dropped to middle B ﬂat, then down to low E ﬂat. This continual alternation of key was the most striking thing about the Hermit's song, apart from its regularity and accuracy of pitch. It suggested, somehow, the orchestral handling of a theme by a musical composer, and made it beyond comparison more in- teresting as a performance than the simple repetitions of the livesbacked Thrush, or the endless variety of the Thrasher.

The utterance of the theme was for all the lower forms distinct and without partamenta. Now and then, although rarely, the bird gave his triplet or quadruple: notes a vibratory “trill,” and in the very highest phrases the distinctness of vocalization was much diminished. The birds voice never broke on its highest' notes, but his enunciation became some- what indistinct, although never to such an extent as to disguise the form

of his theme.

The voice of the Hermit Thrush was made individual by overtones, giving it a considerable richness and penetration and even a metallic burr or buzz. It suggested somewhat the reed-quality of the oboe superadded to a ﬂute's open toner Direct comparison was possible only with the piano, at bugle and a ﬂute, and, needless to say. it was far closer to the last named, but very much more vibrant, less hollow. The “burr” was audible at short ranges only. At a hundred yards or less it blended to give the voice a singularly ringing metallic quality which gave it a carrying power unapproached by any other bird of that region It should be said that in proportion as the bird seemed to be exerting himself, as, for example,