Trivia: Which appliance replaced the group of workers known as “knocker-uppers”?
Correct Answer: Alarm clock
So why is this answer correct? : Starting in the Industrial Revolution, shift workers — especially in England — relied on knocker-uppers to get them up in time for work. Knocker-uppers would use long poles to tap on the windows of sleeping workers to let them know it was time to get up for their shift. By the 1970s, the convenience of alarm clocks proved too alluring to resist, and knocker-uppers became obsolete.