A knocker-up, sometimes known as a knocker-upper, was a profession in Britain and Ireland that started during and lasted well into the Industrial Revolution, when alarm clocks were neither cheap nor reliable, and to as late as the beginning of the 1950s. A knocker-up’s job was to rouse sleeping people so they could get to work on time.
The knocker-up used a baton or short, heavy stick to knock on the clients’ doors or a long and light stick, often made of bamboo, to reach windows on higher floors. At least one of them used a pea-shooter. In return, the knocker-up would be paid a few pence a week. The knocker-up would not leave a client’s window until they were sure that the client had been awoken.