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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. [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.
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.
Stone tool use – early human (hominid) use of stone tool technology, such as the hand axe, was similar to that of primates, which is found to be limited to the intelligence levels of modern children aged 3 to 5 years. Ancestors of homo sapiens (modern man) used stone tools as follows: Homo habilis ("handy man") – first "homo" species.
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 ...
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 ...
The main feature of thermodynamic diagrams is the equivalence between the area in the diagram and energy. When air changes pressure and temperature during a process and prescribes a closed curve within the diagram the area enclosed by this curve is proportional to the energy which has been gained or released by the air.