Every locomotive has a whistle, used by the engineer to communicate with the train crew and the public. The steam whistle, mounted on or near the steam dome, has a pair of resonating cups inverted over a valve, through which small quantities of live steam can be admitted. The resulting high-pitched, melodious tones are controlled by the engineer, who has learned a complex set of signals for such things as starting, stopping, backing up, and approaching road crossings. Whistles don't guarantee safety unless they are heeded—and they have a code of their own.
Quick facts
Remembered with fondness
Whistle in England
Whistle in United States
Moderation essential