They had no Lipps Inc. to start their day to. Most didn’t have access to alarm clocks for that matter. What were they supposed to do? Pay somebody to bang on their door or window every morning until they dragged themselves out of bed?

Necessity is the mother of invention, and when the hey-day of the Industrial Revolution in England demanded that labourers be at their work stations promptly in the mornings that’s exactly what happened and continued to happen regularly right up until the 1930s, then sporadically as late as the early ‘70s.
Those tasked with the often thankless job were called a knocker-upper (or sometimes simply a knocker-up), since the duty’s main component was knocking on either a door or window using a stick or long pole with a best case scenario of waking up the individual that requested the service.
The knocker-upper would be paid for their waking expertise, in some cases having been hired by a local factory or business to make sure their employees would be at work on time. The profession was vital in large centres such as Manchester, and chalk markings on sidewalks in front of houses needing a wakeup call and the requested time were commonplace across the city.
Since the weak link in the chalking system was a good rainfall potentially wiping out a lot of hard work, some knocker-ups started placing signboards on the houses of those who needed to be ‘knocked up’. These signs had the wakeup time posted in addition to the knocker-up’s name as a means to advertise their service.

One of the many downsides to the knocker-up’s professional existence (besides themselves often having be up as early as three in the morning) was dealing with angry, sleepy, and occasionally hung-over individuals. Some of these individuals really had no reason to gripe since they requested the service in the first place.
Others were livid neighbours who had no need to be up before dawn but had been woken by the sound of the knocker-up’s bamboo pole repeatedly tapping on a nearby window. One knocker-up, East Ender Mary Smith, found a way to ease the collateral damage by using a pea shooter to take aim at her clients’ second floor windows.
Her system was annoying enough for the customer to have to go to their window to signal Smith to stop, but not loud enough to have the wrath of the surrounding neighbourhood steered her way. It certainly beat having buckets of water thrown at her as was the fate of some of her professional cohorts, both by their drowsy customers and their customers’ sleep-deprived neighbours. All of this for a few pence a week in the knocker-up’s pocket.
We had a knocker-up, and our knocker-up had a knocker-up. And our knocker-up’s knocker-up didn’t knock our knocker up. So our knocker-up didn’t knock us up. ‘Cos he’s not up.

As to who woke up the knocker-uppers, that scenario was dealt with in different ways. When they became available, some factories would splurge on an alarm clock for their knocker-upper of choice. Often times knocker-uppers were just nighthawks, sleeping during the day and being wide awake when the time came to start their early morning rounds of peashooting and window tapping.
John Stead does a fine job explaining and immortalising the knocker-up profession in his song, ‘The Knocker Up Man’. It’s almost as good as ‘Funky Town’.
Sources
- Israel, D., 2010. 7 Ways People Woke up, Pre-Alarm Clock http://mentalfloss.com/article/24117/7-ways-people-woke-pre-alarm-clock
- Walton, G., 2014. Knocker-Up http://www.geriwalton.com/index.php/2014/02/knocker-up/
- Lewis, D., 2015. Knockered Up http://nowiknow.com/knockered-up/
- Strauss, M., 2011. Old English Occupation: Knocker-up Keeping Employees Working http://genealogyresearchnetwork.com/2011/10/old-english-occupation-knocker-up-keeping-employees-working/