Doc Song

Of a sudden, a weird sound permeated the surrounding air. It was a trilling, mellow, subdued sound, reminiscent of the song of some strange jungle bird, or the dulcet note of a wind filtering through a leafless forest. Having no tune, it was nevertheless melodious. Not awesome, it still had a quality to excite, to inspire.

This sound was part of Doc--a small, unconscious thing which accompanied his moments of utter concentration. It would come from his lips when a plan of action was being evolved, or in the midst of some struggle, or when some beleaguered friend of Doc's, alone and attacked, had almost given up hope of life. And with the filtering through of that sound would come renewed hope.

The strange trilling had the weird essence of seeming to emanate from everywhere instead of from a particular spot. Even one looking directly at Doc's lips would not realize from whence it arose.

- The Land of Terror (1933) Chapter 2