You'd be hard-pressed to find a gadget that went through more wacky prototypes than the vacuum cleaner. Historians credit the development of this appliance directly to the reduced availability of servants to do the carpet beating and the sweeping in the early 20th century.
But the evidence shows that these early vacuum cleaners didn't do much to make the job easier.
The first patent for a carpet-cleaning machine was filed in 1860, and it employed a bellows to create suction [source: Kautzman]. Later innovations involved a hand pump that required two people to operate -- one to pump and one to steer.
The plunger model appeared after 1900. It used a simple principle: Pull up the pump and suck up the dirt. It only worked on thin carpets. Wheel-operated models worked better. Though many of the wheel-driven models required two people to operate, they pulled in dirt so well that they remained in service well into the 20th century, when electric models reached the market.