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London sinks were originally shallower than Belfast sinks. [5] (One plumbing guide in 1921 suggested that the Belfast sink was 38 centimetres (15 in) deep.) [7] Some believe this was because London had less access to fresh water (and thus a greater need to conserve water), but this theory is now contested. It is more likely the two sinks had ...
Ancient stone tools from Ethiopia were hand-crafted by Australopithecus or related people. [1] [2] [further explanation needed] 2.3 Mya: Earliest likely control of fire and cooking, by Homo habilis [3] [4] [5] 1.76 Mya: Advanced stone tools in Kenya by Homo erectus [6] [7] 1.75 Mya – 150 kya: Varying estimates for the origin of language [8] [9]
By 1965, around 75% of U.S. breweries were using them, but in the mid-1970s, pressure from environmentalists due to litter led to the development of the non-removable tabs used today. By 1980, his company was supplying can-end machinery worldwide making over $500 million in annual revenue.
Dean began investigating the epidemiology of fluorosis in 1931. By the late 1930s, he and his staff had made a critical discovery. Namely, fluoride levels of up to 1.0 ppm in drinking water did not cause enamel fluorosis in most people and only mild enamel fluorosis in a small percentage of people.
Mudbricks faced were burnt brick set in bitumen were used to originally construct the Ziggurat of Ur. [ 17 ] The wheel was invented by the Sumerians in the copper age but it will not be until around 3500 BC when it will be used in transportation. [ 6 ]
This kitchen measured 1.9 by 3.4 metres (6 ft 3 in by 11 ft 2 in), and was built to optimize kitchen efficiency and lower building costs. The design was the result of detailed time-motion studies and interviews with future tenants to identify what they needed from their kitchens.
Woman on an Israeli kibbutz using a washboard to do laundry. A washboard or a scrubbing-board [1] is a tool designed for hand washing clothing. With mechanized cleaning of clothing becoming more common by the end of the 20th century, the washboard has become better known for its secondary use as a musical instrument.
Italian physicist and electrical engineer Galileo Ferraris publishes a paper on the induction motor, and Serbian-American engineer Nikola Tesla gets a US patent on the same device [4] [5] 1890: Thomas Alva Edison invents the fuse: 1893: During the Fourth International Conference of Electricians in Chicago, electrical units were defined 1893