key-bugle

The lively notes of the guard's key-bugle vibrate in the clear cold air, and wake up the old gentleman inside, who, carefully letting down the window-sash half-way, and standing sentry over the air, takes a short peep out, and then carefully pulling it up again, informs the other inside that they're going to change directly; on which the other inside wakes himself up, and determines to postpone his next nap until after the stoppage.

We had no lack of music, for one played the accordion, another the violin, and another (who usually began at six o'clock A.M.) the key-bugle: the combined effect of which instruments, when they all played different tunes in differents parts of the ship, at the same time, and within hearing of each other, as they sometimes did (everybody being intensely satisfied with his own performance), was sublimely hideous.

He winked, as he spoke, at two of the company, who were known officially as the "bassoon" and the "key-bugle", in the confidence that he was expressing the sense of the musical profession in Raveloe.