Mary Smith earned sixpence a week shooting dried peas at sleeping workers windows. A Knocker-up (sometimes known as a knocker-upper) was a profession in England and Ireland that started during and lasted well into the Industrial Revolution and at least as late as the 1920s, before alarm clocks were affordable or reliable. A knocker-upper’s job was to rouse sleeping people so they could get to work on time.
It’s very interesting to me to see how words and phrases have been misconstrued and perverted by other innuendos, and ambiguous meanings as time unfolds. Today, in the year 2015, if you were to advise someone that you are a professional “knocker-upper” … it certainly would not carry the same meaning as it did in it’s original time period. Furthermore, due to great advances in technology, this particular career seems ludicrous and humorously irrelevant.