Vacuum Cleaner -- I
A vacuum cleaner is a device that uses an air pump (a centrifugal fan in all but some of the very oldest models), to create a partial vacuum to suck up dust and dirt, usually from floors, and optionally from other surfaces as well. The dirt is collected by either a dust bag or a cyclone for later disposal. Vacuum cleaners, which are used in homes as well as in industry, exist in a variety of sizes and models—small battery-powered hand-held devices, domestic central vacuum cleaners, huge stationary industrial appliances that can handle several hundred litters of dust before being emptied, and self-propelledvacuum trucks for recovery of large spills or removal of contaminated soil.
The motorized vacuum cleaner was invented by Hubert Cecil Booth of England in 1901. As Booth recalled decades later, that year he attended "a demonstration of an American machine by its inventor" at the Empire Music Hall in London. The inventor is not named, but Booth's description of the machine conforms fairly closely to Thurman's design, as modified in later patents. Booth watched a demonstration of the device, which blew dust off the chairs, and thought that "...if the system could be reversed, and a filter inserted between the suction apparatus and the outside air, whereby the dust would be retained in a receptacle, the real solution of the hygienic removal of dust would be obtained. He tested the idea by laying a handkerchief on the seat of a restaurant chair, putting his mouth to the handkerchief, and then trying to suck up as much dust as he could onto the handkerchief. Upon seeing the dust and dirt collected on the underside of the handkerchief, he realized the idea could work.