In 1901, British civil engineer Booth went to the Empire Concert Hall in Leicester Square, London, to watch a demonstration of an American car dust collector. This kind of vacuum cleaner uses compressed air to blow dust into a container. Booth thinks this method is not very clever because a lot of dust fails to be blown into the container. Later, he did the opposite and used the vacuuming method. Booth made a very simple experiment: covered a handkerchief on the armrest of a chair, and sucked it off with his mouth. As a result, the handkerchief was attached with a layer of vacuum. dust. At that time, he made a vacuum cleaner, using a powerful electric pump to suck air into the hose and filter the dust through a cloth bag. In August 1901, Booth obtained the patent and established a vacuum cleaner company, but did not sell vacuum cleaners. He installed a vacuum pump driven by a gasoline engine on a horse-drawn carriage and provided door-to-door service. He extended three or four long hoses from the window into the room to vacuum, and all company employees wore work clothes. This was the predecessor of the later vacuum cleaner. sanyo Sanyo horizontal vacuum cleaner In 1902, Booth's service company was called to Westminster Abbey to clean the carpet used in the coronation ceremony of Edward VII. Since then, business has been booming. In 1906, Booth made a small household vacuum cleaner. Although it was called "small", the vacuum cleaner weighed 88 pounds (1 pound = 0.4536 kilograms) and was too bulky to be popularized. In 1907, Spangula, an inventor in Ohio, USA, made a lightweight vacuum cleaner. He was working as a manager in a store at the time. To relieve his son from the burden of cleaning carpets, he made a vacuum cleaner that used an electric fan to create a vacuum and suck dust into the machine. , and then blown into the pocket. Since he was unable to produce and sell it himself, he transferred the patent to the fur manufacturer Hoover in 1908. At that time, Hoover began to manufacture a wheeled "O" type vacuum cleaner, which sold very well. This earliest household vacuum cleaner had a reasonable design, and it has not changed much in principle since its development. The earliest vacuum cleaners designed were upright. In 1913 Wenler G?ring of Stockholm, Sweden invented the horizontal canister vacuum cleaner.