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🔗 Death 🔗 Ancient Egypt 🔗 Ancient Egypt/Egyptian religion

The Coffin Texts are a collection of ancient Egyptian funerary spells written on coffins beginning in the First Intermediate Period. They are partially derived from the earlier Pyramid Texts, reserved for royal use only, but contain substantial new material related to everyday desires, indicating a new target audience of common people. Ordinary Egyptians who could afford a coffin had access to these funerary spells and the pharaoh no longer had exclusive rights to an afterlife.

As the modern name of this collection of some 1,185 spells implies, they were mostly inscribed on Middle Kingdom coffins. They were also sometimes written on tomb walls, stelae, canopic chests, papyri and mummy masks. Due to the limited writing surfaces of some of these objects, the spells were often abbreviated, giving rise to long and short versions, some of which were later copied in the Book of the Dead.

🔗 Technology

A Tesla valve, called by Tesla a valvular conduit, is a fixed-geometry passive check valve. It allows a fluid to flow preferentially in one direction, without moving parts. The device is named after Nikola Tesla, who was awarded U.S. Patent 1,329,559 in 1920 for its invention. The patent application describes the invention as follows:

The interior of the conduit is provided with enlargements, recesses, projections, baffles, or buckets which, while offering virtually no resistance to the passage of the fluid in one direction, other than surface friction, constitute an almost impassable barrier to its flow in the opposite direction.

Tesla illustrates this with the drawing, showing one possible construction with a series of eleven flow-control segments, although any other number of such segments could be used as desired to increase or decrease the flow regulation effect.

One computational fluid dynamics simulation of Tesla valves with two and four segments showed that the flow resistance in the blocking (or reverse) direction was about 15 and 40 times greater, respectively, than the unimpeded (or forward) direction. This lends support to Tesla's patent assertion that in the valvular conduit in his diagram, a pressure ratio "approximating 200 can be obtained so that the device acts as a slightly leaking valve".

The Tesla valve is used in microfluidic applications and offers advantages such as scalability, durability, and ease of fabrication in a variety of materials.

🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Lists 🔗 Military history/Intelligence 🔗 Military history/Military land vehicles

This page contains a list of military tactics.

The meaning of the phrase is context sensitive, and has varied over time, like the difference between "strategy" and "tactics".

🔗 Germany 🔗 Folklore

In German folklore, a wolpertinger (also called wolperdinger or woiperdinger) is an animal said to inhabit the alpine forests of Bavaria and Baden-Württemberg in Germany.

🔗 Russia 🔗 Agriculture 🔗 Food and drink 🔗 Russia/physical geography of Russia 🔗 Russia/economy of Russia

Kostroma Moose Farm (Russian: Костромска́я лосефе́рма) is an experimental farm in Kostroma Oblast, Russia, where a herd of moose is kept, primarily for milk production; the farm supplies moose's milk to a nearby sanitorium. It is located near the village of Sumarokovo in Krasnoselsky District of Kostroma Oblast, some 25 km east of the city of Kostroma.

🔗 Electronics

A magic eye tube or tuning indicator, in technical literature called an electron-ray indicator tube, is a vacuum tube which gives a visual indication of the amplitude of an electronic signal, such as an audio output, radio-frequency signal strength, or other functions. The magic eye (also called a cat's eye, or tuning eye in North America) is a specific type of such a tube with a circular display similar to the EM34 illustrated. Its first broad application was as a tuning indicator in radio receivers, to give an indication of the relative strength of the received radio signal, to show when a radio station was properly tuned in.

The magic eye tube was the first in a line of development of cathode ray type tuning indicators developed as a cheaper alternative to the needle movement meters. It was not until the 1960s that needle meters were made economically enough in Japan to displace indicator tubes. Tuning indicator tubes were used in vacuum tube receivers from around 1936 to 1980 before vacuum tubes were replaced by transistors in radios. An earlier tuning aid which the magic eye replaced was the "tuneon" neon lamp.

🔗 Technology 🔗 Law 🔗 Business 🔗 Occupational Safety and Health

A stenotype, stenotype machine, shorthand machine or steno writer is a specialized chorded keyboard or typewriter used by stenographers for shorthand use. In order to pass the United States Registered Professional Reporter test, a trained court reporter or closed captioner must write speeds of approximately 180, 200, and 225 words per minute (wpm) at very high accuracy in the categories of literary, jury charge, and testimony, respectively. Some stenographers can reach 300 words per minute. The website of the California Official Court Reporters Association (COCRA) gives the official record for American English as 375 wpm.

The stenotype keyboard has far fewer keys than a conventional alphanumeric keyboard. Multiple keys are pressed simultaneously (known as "chording" or "stroking") to spell out whole syllables, words, and phrases with a single hand motion. This system makes real-time transcription practical for court reporting and live closed captioning. Because the keyboard does not contain all the letters of the English alphabet, letter combinations are substituted for the missing letters. There are several schools of thought on how to record various sounds, such as the StenEd, Phoenix, and Magnum Steno theories.

🔗 Ancient Near East 🔗 Meteorology 🔗 Meteorology/droughts and fire events 🔗 Ancient Egypt

The 4.2-kiloyear BP aridification event was one of the most severe climatic events of the Holocene epoch. It defines the beginning of the current Meghalayan age in the Holocene epoch. Starting in about 2200 BC, it probably lasted the entire 22nd century BC. It has been hypothesised to have caused the collapse of the Old Kingdom in Egypt as well as the Akkadian Empire in Mesopotamia, and the Liangzhu culture in the lower Yangtze River area. The drought may also have initiated the collapse of the Indus Valley Civilisation, with some of its population moving southeastward to follow the movement of their desired habitat, as well as the migration of Indo-European-speaking people into India.

Some scientists disagree with this conclusion and point out that the event was neither a global drought nor did it happen in a clear timeline.

🔗 Military history 🔗 Military history/Early Modern warfare 🔗 Military history/American Revolutionary War 🔗 Military history/Maritime warfare 🔗 Ships 🔗 Connecticut

Turtle (also called American Turtle) was the world's first submersible vessel with a documented record of use in combat. It was built in 1775 by American David Bushnell as a means of attaching explosive charges to ships in a harbor, for use against Royal Navy vessels occupying North American harbors during the American Revolutionary War. Connecticut Governor Jonathan Trumbull recommended the invention to George Washington, who provided funds and support for the development and testing of the machine.

Several attempts were made using Turtle to affix explosives to the undersides of British warships in New York Harbor in 1776. All failed, and her transport ship was sunk later that year by the British with the submarine aboard. Bushnell claimed eventually to have recovered the machine, but its final fate is unknown. Modern replicas of Turtle have been constructed and are on display in the Connecticut River Museum, the U.S. Navy's Submarine Force Library and Museum, the Royal Navy Submarine Museum, and the Oceanographic Museum (Monaco).

🔗 Food and drink 🔗 Guild of Copy Editors

A perpetual stew, also known as hunter's pot or hunter's stew, is a pot into which whatever one can find is placed and cooked. The pot is never or rarely emptied all the way, and ingredients and liquid are replenished as necessary. The concept is often a common element in descriptions of medieval inns. Foods prepared in a perpetual stew have been described as being flavorful due to the manner in which the foodstuffs blend together, in which the flavor may improve with age.