"A forgotten profession: In the days before alarm clocks were widely affordable, people like Mary Smith of Brenton Street were employed to rouse sleeping people in the early hours of the morning. They were commonly known as ‘knocker-ups’ or ‘knocker-uppers’. Mrs. Smith was paid sixpence a week to shoot dried peas at market workers’ windows in Limehouse Fields, London. Photograph from Philip Davies’ Lost London: 1870-1945."
Different perspective provides a different meaning to that phrase?