LONDON — Ask not for whom the bell tolls — at least not for the next four years at Parliament.

Big Ben’s distinctive and reassuring chimes, which have marked the passage of time since the Victorian era, fell silent after ringing out at noon on Monday as a $37 million restoration project got underway for the tower that houses the bell.

Crowds gathered around Parliament to hear the final set of bongs that have been an almost constant presence, heard not just in London but around the world: Two BBC News bulletins each day, at 6 p.m. and midnight, begin with the famous sound, which the broadcaster first used in 1924.

During World War II, when the bells carried on tolling after a brief interlude, the sound of Big Ben gave troops a lift in morale and provided hope to those in occupied countries like France.