2 examples of two-tone in sentences

The mellow resonance of a two-toned automobile horn, disturbing the early evening hush and at the same time Duchemin's meditations, recalled him to Nant in time to see a touring car of majestic proportions and mien which, coming from the south, from the direction of the railroad and Nimes, was sweeping a fine curve round two sides of the public square.

The rub was there; the quarter seemed quite fast asleep; in the five minutes which had elapsed since Lanyard had ensconced himself in the doorway no motor car had passed, not a footfall had disturbed the stillness, never a sound of any sort had come to his attention other than one distant blare of a two-toned automobile horn from the neighbourhood of the Arc de Triomphe.

2 examples of  two-tone  in sentences