What is a quavering modulation of the voice; a musical trill; a song. And he, the wondrous child, Whose silver warble wild Outvalued every pulsing sound. Emerson called?

warble — A quavering modulation of the voice; a musical trill; a song. And he, the wondrous child, Whose silver warble wild Outvalued every pulsing sound. Emerson. (Webster's 1913.)

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