Grain-grinding
31Quern-stone — The upper stone of a Scottish hand quern from Dalgarven Mill, North Ayrshire. Quern stones are stone tools for hand grinding a wide variety of materials. They were used in pairs. The lower, stationary, stone is called a quern, whilst the upper,… …
32Ohalo — is the common designation for the archaeological site Ohalo II, which is located near the Sea of Galilee in modern day Israel, and one of the best preserved hunter gatherer archaeological sites of the Last Glacial Maximum, having been radiocarbon …
33agriculture, origins of — Introduction the active production of useful plants or animals in ecosystems that have been created by people. Agriculture has often been conceptualized narrowly, in terms of specific combinations of activities and organisms wet rice production… …
34Drill bit — For the fictional character, see Drill Bit (Transformers). For the cancelled skyscraper nicknamed Drill bit, see Chicago Spire. For the types used in drilling wells, see Well drilling. From top to bottom: Spade, lip and spur (brad point), masonry …
35Ceramography — is the art and science of preparation, examination and evaluation of ceramic microstructures.[1] Ceramography can be thought of as the metallography of ceramics. The microstructure is the structure level of approximately 0.1 to 100 µm, between… …
36Metallography — A micrograph of bronze revealing a cast dendritic structure Metallography is the study of the physical structure and components of metals, typically using microscopy. Ceramic and polymeric materials may also be prepared using metallographic… …
37energy conversion — ▪ technology Introduction the transformation of energy from forms provided by nature to forms that can be used by humans. Over the centuries a wide array of devices and systems has been developed for this purpose. Some of these energy …
38Flour — For other uses, see Flour (disambiguation). A paper sack of wheat flour, with a metal measuring scoop. Flour is a powder which is made from grinding cereal grains, other seeds or roots (like Cassava). It is the main ingredient of bread, which is… …
39millstone — /mil stohn /, n. 1. either of a pair of circular stones between which grain or another substance is ground, as in a mill. 2. anything that grinds or crushes. 3. any heavy mental or emotional burden (often used in the phrase a millstone around one …
40Watermill — This article is about a type of structure. For other locational uses see Milldam . For details of the technologies, see Water wheel and Mill machinery . A watermill is a structure that uses a water wheel or turbine to drive a mechanical process… …
