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Many such sites have hominin bones, teeth, or footprints, but unless they also include evidence for tools or tool use, they are omitted here. This list excludes tools and tool use attributed to non-hominin species. See Tool use by non-humans. Since there are far too many hominin tool sites to list on a single page, this page attempts to list ...
The Assyrian King Sennacherib (704–681 BC) claims to have invented automatic sluices and to have been the first to use water screw pumps, of up to 30 tons weight, which were cast using two-part clay molds rather than by the 'lost wax' process. [17] The Jerwan Aqueduct (c. 688 BC) is made with stone arches and lined with waterproof concrete. [25]
The light mill is uniformly coated by gold nanocrystals, which are a strong light absorber. Upon exposure, due to geometric effect, the convex side of the vane receives more photon energy than the concave side does, and subsequently the gas molecules receive more heat from the convex side than from the concave side.
1701 — Newton publishes anonymously a method of determining the rate of heat loss of a body and introduces a scale, which had 0 degrees represent the freezing point of water, and 12 degrees for human body temperature. He used linseed oil as the thermometric fluid. [6] 1701 — Ole Christensen Rømer made one of the first practical ...
1963 Kurt Schmidt invents the first high pressure sodium-vapor lamp. [19] 1972 M. George Craford invents the first yellow light-emitting diode. 1972 Herbert Paul Maruska and Jacques Pankove create the first violet light-emitting diode. 1981 Philips sells their first Compact Fluorescent Energy Saving Lamps, with integrated conventional ballast.
The Stone Age is a broad prehistoric period during which stone was widely used in the manufacture of implements with a sharp edge, a point, or a percussion surface. The period lasted roughly 2.5 million years, from the time of early hominids to Homo sapiens in the later Pleistocene era, and largely ended between 6000 and 2000 BCE with the advent of metalworking.
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Among the many people who attempted to claim the prize was the Yorkshire clockmaker Jeremy Thacker, who first used the term chronometer in a pamphlet published in 1714. [152] Huygens built the first sea clock, designed to remain horizontal aboard a moving ship, but that stopped working if the ship moved suddenly.