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 and at least as late as the 1920s (mid 50s in Manchester, England.
Knocker-up (иногда употреблялось название knocker-upper) — профессия в Англии и Ирландии, возникшая во время промышленной революции и существовавшая до 1920-х годов.