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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 ...
1963 Kurt Schmidt invents the first high pressure sodium-vapor lamp. [18] 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.
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 ...
White differentiates between five stages of human development: In the first, people use the energy of their own muscles. In the second, they use the energy of domesticated animals. In the third, they use the energy of plants (agricultural revolution). In the fourth, they learn to use the energy of natural resources: coal, oil, gas.
The screw pump is the oldest positive displacement pump. [1] The first records of a water screw, or screw pump, date back to Hellenistic Egypt before the 3rd century BC. [1] [3] The Egyptian screw, used to lift water from the Nile, was composed of tubes wound round a cylinder; as the entire unit rotates, water is lifted within the spiral tube to the higher elevation.
Sundials and water clocks were first used in ancient Egypt c. 1200 BC and later by the Babylonians, the Greeks and the Chinese. Incense clocks were being used in China by the 6th century. In the medieval period, Islamic water clocks were unrivalled in their sophistication until the mid-14th century.
The control of fire by early humans was a critical technology enabling the evolution of humans. Fire provided a source of warmth and lighting, protection from predators (especially at night), a way to create more advanced hunting tools, and a method for cooking food. These cultural advances allowed human geographic dispersal, cultural ...
Watt's indicator diagram. The PV diagram, then called an indicator diagram, was developed in 1796 by James Watt and his employee John Southern. [2] Volume was traced by a plate moving with the piston, while pressure was traced by a pressure gauge whose indicator moved at right angles to the piston. A pencil was used to draw the diagram.