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Read the following encyclopedia excerpts to find out about the invention of some items that are part of our daily life . For each excerpt , find a fact that was new or surprising to you . Toothpaste About 5 , 000 years ago , a paste was made from powdered * ashes , eggshells , pieces of rock and herbs . This paste was used by the ancient Egyptians to clean their teeth — using their fingers , not a toothbrush . The Greeks and Romans changed and improved this paste . During the 1 8 ' ' and 1 19 " centuries , many small companies began producing tooth creams or tooth powders . The first mass-produced toothpaste was introduced by the Colgate Company in 1873 . Their product was called "Colgate Dental Cream . " It soon became popular because it smelled and tasted much better than any other product on the market . In 1 896 , Colgate Dental Cream was packaged in tubes similar to those in use today . Today , toothpaste has fluoride and other chemicals which help to keep our teeth healthy . The Dishwasher The first automatic dishwasher was invented by Josephine Cochrane . This wealthy woman from Illinois had a lot of dinner parties . Although she had servants to wash her dishes , she wanted a machine that could do the job faster and without breaking the dishes . So in 1 886 , she decided to build one . She built metal compartments * to hold the dishes . These compartments were put in a big metal box that had a wheel . This wheel was turned by a motor while hot soapy water was squirted * up and down onto the dishes . Her invention was first shown at the 1 893 World's Fair in Chicago . Soon , restaurants and hotels around the country wanted dishwashers . The design was patented and Josephine Cochrane began to manufacture and sell dishwashers . * powdered — something that has been crushed into very tiny pieces , e . g . flour . * compartments — sections of something , usually closed . * squirted — forced out in a thin stream . Patents Inventors send their invention to a government office . The office registers the invention in the inventor ' s name . This means that the invention belongs to the inventor , so it cannot be used or sold without his or her permission . Dishwasher in the early 1950 s : making housework easier

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