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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 ...
A squeegee or squilgee is a tool with a flat, smooth rubber blade, used to remove or control the flow of liquid on a flat surface. It is used for cleaning and in printing. The earliest written references to squeegees date from the mid-18th century and concern deck-cleaning tools, some with leather rather than rubber blades. The name "squeegee ...
Detail of a cubit rod in the Museo Egizio of Turin The earliest recorded systems of weights and measures originate in the 3rd or 4th millennium BC. Even the very earliest civilizations needed measurement for purposes of agriculture, construction and trade. Early standard units might only have applied to a single community or small region, with every area developing its own standards for ...
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.
[43]: 38 Most water and wind power was used for milling grain. Water power was also used for blowing air in blast furnace, pulping rags for paper making and for felting wool. The Domesday Book recorded 5,624 water mills in Great Britain in 1086, being about one per thirty families. [43]
pressure of a liquid or gas in a closed tube ruler: for measuring length saccharometer: amount of sugar in a solution seismometer: seismic waves (for example, earthquakes) sextant: location on Earth's surface (used in naval navigation) spectrometer: properties of light spectrophotometer: intensity of light as a function of wavelength speedometer
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.
A gravimetric hygrometer extracts the water from the air (or other gas) and weighs it separately, for example by weighing a desiccant before and after it has absorbed the water. The temperature, pressure and volume of the resulting dry gas are also measured, providing enough information to calculate the amount of water per mole of gas. [8] [9]