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🔗 United States 🔗 California 🔗 Disaster management 🔗 Oregon 🔗 United States/Utah 🔗 Weather 🔗 Weather/Non-tropical storms 🔗 Weather/Floods

The Great Flood of 1862 was the largest flood in the recorded history of Oregon, Nevada, and California, occurring from December 1861 to January 1862. It was preceded by weeks of continuous rains and snows in the very high elevations that began in Oregon in November 1861 and continued into January 1862. This was followed by a record amount of rain from January 9–12, and contributed to a flood that extended from the Columbia River southward in western Oregon, and through California to San Diego, and extended as far inland as Idaho in the Washington Territory, Nevada and Utah in the Utah Territory, and Arizona in the western New Mexico Territory. The event dumped an equivalent of 10 feet (3.0 m) of water in California, in the form of rain and snow, over a period of 43 days. Immense snowfalls in the mountains of far western North America caused more flooding in Idaho, Arizona, New Mexico, as well as in Baja California and Sonora, Mexico the following spring and summer, as the snow melted.

The event was capped by a warm intense storm that melted the high snow load. The resulting snow-melt flooded valleys, inundated or swept away towns, mills, dams, flumes, houses, fences, and domestic animals, and ruined fields. It has been described as the worst disaster ever to strike California. The storms caused approximately $100 million (1861 USD) in damage, approximately equal to $3.117 billion (2021 USD). The governor, state legislature, and state employees were not paid for a year and a half. At least 4,000 people were estimated to have been killed in the floods in California, which was roughly 1% of the state population at the time.

🔗 United States 🔗 Russia 🔗 Military history 🔗 United States/Military history - U.S. military history 🔗 Korea 🔗 China 🔗 Military history/World War II 🔗 Japan 🔗 Russia/history of Russia 🔗 Japan/Japanese military history 🔗 Military history/Asian military history 🔗 Military history/Japanese military history 🔗 Korea/Korean military history

Unit 731 (Japanese: 731部隊, Hepburn: Nana-san-ichi Butai), also referred to as Detachment 731, the 731 Regiment, Manshu Detachment 731, The Kamo Detachment, Ishii Unit, Ishii Detachment or the Ishii Company, was a covert biological and chemical warfare research and development unit of the Imperial Japanese Army that undertook lethal human experimentation during the Second Sino-Japanese War (1937–1945) of World War II. It was responsible for some of the most notorious war crimes carried out by Imperial Japan. Unit 731 was based at the Pingfang district of Harbin, the largest city in the Japanese puppet state of Manchukuo (now Northeast China), and had active branch offices throughout China and Southeast Asia.

Its parent program was officially known as the Epidemic Prevention and Water Purification Department of the Kwantung Army (関東軍防疫給水部本部, Kantōgun Bōeki Kyūsuibu Honbu). Originally set up under the Kempeitai military police of the Empire of Japan, Unit 731 was taken over and commanded until the end of the war by General Shirō Ishii, a combat medic officer in the Kwantung Army. The facility itself was built in 1935 as a replacement for the Zhongma Fortress, and to expand the capabilities for Ishii and his team. The program received generous support from the Japanese government up to the end of the war in 1945.

Unit 731 and the other Units of the "Epidemic Prevention and Water Purification Department" were biological weapon production, testing, deployment and storage facilities. They routinely tested on human beings (who were referred to internally as "logs"). Additionally, the biological weapons were tested in the field on cities and towns in China. Estimates of those killed by Unit 731 and its related programs range up to half a million people.

The researchers involved in Unit 731 were secretly given immunity by the U.S. in exchange for the data they gathered through human experimentation. Other researchers that the Soviet forces managed to arrest first were tried at the Khabarovsk War Crime Trials in 1949. The Americans did not try the researchers so that the information and experience gained in bio-weapons could be co-opted into the U.S. biological warfare program, much as they had done with German researchers in Operation Paperclip. On 6 May 1947, Douglas MacArthur, as Supreme Commander of the Allied Forces, wrote to Washington that "additional data, possibly some statements from Ishii, can probably be obtained by informing Japanese involved that information will be retained in intelligence channels and will not be employed as 'War Crimes' evidence". Victim accounts were then largely ignored or dismissed in the West as communist propaganda.

🔗 China/Chinese history 🔗 China 🔗 Toys 🔗 Project-independent assessment

The bamboo-copter, also known as the bamboo dragonfly or Chinese top (Chinese zhuqingting (竹蜻蜓), Japanese taketonbo 竹蜻蛉), is a toy helicopter rotor that flies up when its shaft is rapidly spun. This helicopter-like top originated in Jin dynasty China around 320 AD, and was the object of early experiments by English engineer George Cayley, the inventor of modern aeronautics.

In China, the earliest known flying toys consisted of feathers at the end of a stick, which was rapidly spun between the hands and released into flight. "While the Chinese top was no more than a toy, it is perhaps the first tangible device of what we may understand as a helicopter."

The Jin dynasty Daoist philosopher Ge Hong's (c. 317) book Baopuzi (抱樸子 "Master Who Embraces Simplicity") mentioned a flying vehicle in what Joseph Needham calls "truly an astonishing passage".

Some have made flying cars [feiche 飛車] with wood from the inner part of the jujube tree, using ox-leather (straps) fastened to returning blades so as to set the machine in motion [huan jian yi yin chiji 環劍以引其機]. Others have had the idea of making five snakes, six dragons and three oxen, to meet the "hard wind" [gangfeng 罡風] and ride on it, not stopping until they have risen to a height of forty li. That region is called [Taiqing 太清] (the purest of empty space). There the [qi] is extremely hard, so much so that it can overcome (the strength of) human beings. As the Teacher says: "The kite (bird) flies higher and higher spirally, and then only needs to stretch its two wings, beating the air no more, in order to go forward by itself. This is because it starts gliding (lit. riding) on the 'hard wind' [gangqi 罡炁]. Take dragons, for example; when they first rise they go up using the clouds as steps, and after they have attained a height of forty li then they rush forward effortlessly (lit. automatically) (gliding)." This account comes from the adepts [xianren 仙人], and is handed down to ordinary people, but they are not likely to understand it.

Needham concludes that Ge Hong was describing helicopter tops because "'returning (or revolving) blades' can hardly mean anything else, especially in close association with a belt or strap"; and suggests that "snakes", "dragons", and "oxen" refer to shapes of man-lifting kites. Other scholars interpret this Baopuzi passage mythologically instead of literally, based on its context's mentioning fantastic flights through chengqiao (乘蹻 "riding on tiptoe/stilts") and xian (仙 "immortal; adept") techniques. For instance, "If you can ride the arches of your feet, you will be able to wander anywhere in the world without hindrance from mountains or rivers … Whoever takes the correct amulet and gives serious thought to the process may travel a thousand miles by concentrating his thoughts for one double hour." Compare this translation.

Some build a flying vehicle from the pith of the jujube tree and have it drawn by a sword with a thong of buffalo hide at the end of its grip. Others let their thoughts dwell on the preparation of a joint rectangle from five serpents, six dragons, and three buffaloes, and mount in this for forty miles to the region known as Paradise.

This Chinese helicopter toy was introduced into Europe and "made its earliest appearances in Renaissance European paintings and in the drawings of Leonardo da Vinci." The toy helicopter appears in a c. 1460 French picture of the Madonna and Child at the Musée du Palais de Tesse’ in Mans depicting the Child holding a toy copter sitting in Mary’s lap next to St Benôit (unknown artist), and in a 16th-century stained glass panel at the Victoria and Albert Museum in London. A picture from c. 1560 by Pieter Breughel the Elder at the Kunsthistorisches Museum in Vienna, Children's Games, depicts a helicopter top with three airscrews.

"The helicopter top in China led to nothing but amusement and pleasure, but fourteen hundred years later it was to be one of the key elements in the birth of modern aeronautics in the West." Early Western scientists developed flying machines based upon the original Chinese model. The Russian polymath Mikhail Lomonosov developed a spring-driven coaxial rotor in 1743, and the French naturalist Christian de Launoy created a bow drill device with contra-rotating feather propellers.

In 1792, George Cayley began experimenting with helicopter tops, which he later called "rotary wafts" or "elevating fliers". His landmark (1809) article "On Aerial Navigation" pictured and described a flying model with two propellers (constructed from corks and feathers) powered by a whalebone bow drill. "In 1835 Cayley remarked that while the original toy would rise no more than about 20 or 25 feet (6 or 7.5 metres), his improved models would 'mount upward of 90 ft (27 metres) into the air'. This then was the direct ancestor of the helicopter rotor and the aircraft propeller."

Discussing the history of Chinese inventiveness, the British scientist, sinologist, and historian Joseph Needham wrote, "Some inventions seem to have arisen merely from a whimsical curiosity, such as the 'hot air balloons' made from eggshells which did not lead to any aeronautical use or aerodynamic discoveries, or the zoetrope which did not lead onto the kinematograph, or the helicopter top which did not lead to the helicopter."

🔗 United States 🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Korea

A graphite bomb is intended to be a non-lethal weapon used to disable an electrical grid. The bomb works by spreading a dense cloud of extremely fine, chemically treated carbon filaments over air-insulated high voltage installations like transformers and power lines, causing short-circuits and subsequent disruption of the electricity supply in an area, a region or even an entire small country. The weapon is sometimes referred to as blackout bomb or as soft bomb because its direct effects are largely confined to the targeted electrical power facility, with minimal risk of immediate collateral damage. However, since water supply systems and sewage treatment systems depend on electricity, widespread outbreaks of cholera and other waterborne diseases, causing large numbers of civilian deaths, have in the past been the direct consequence of this bomb's use.

🔗 Computing/Free and open-source software

🔗 Technology

Tensegrity, tensional integrity or floating compression is a structural principle based on a system of isolated components under compression inside a network of continuous tension, and arranged in such a way that the compressed members (usually bars or struts) do not touch each other while the prestressed tensioned members (usually cables or tendons) delineate the system spatially.

The term was coined by Buckminster Fuller in the 1960s as a portmanteau of "tensional integrity". The other denomination of tensegrity, floating compression, was used mainly by the constructivist artist Kenneth Snelson.

🔗 Companies 🔗 Aviation 🔗 Spaceflight 🔗 Aviation/aircraft 🔗 Rocketry

Rotary Rocket Company was a rocketry company that developed the Roton concept in the late 1990s as a fully reusable single-stage-to-orbit (SSTO) crewed spacecraft. The design was initially conceived by Bevin McKinney, who shared it with Gary Hudson. In 1996, Rotary Rocket Company was formed to commercialize the concept. The Roton was intended to reduce costs of launching payloads into low earth orbit by a factor of ten.

The company gathered considerable venture capital from angel investors and opened a factory headquartered in a 45,000-square-foot (4,200 m²) facility at Mojave Air and Space Port in Mojave, California. The fuselage for their vehicles was made by Scaled Composites, at the same airport, while the company developed the novel engine design and helicopter-like landing system. A full-scale test vehicle made three hover flights in 1999, but the company exhausted its funds and closed its doors in early 2001.

🔗 Religion 🔗 Visual arts 🔗 Buddhism 🔗 Asia

The Greco-Buddhist art or Gandhara art is the artistic manifestation of Greco-Buddhism, a cultural syncretism between Ancient Greek art and Buddhism. It had mainly evolved in the ancient region of Gandhara, located in the northwestern fringe of the Indian subcontinent.

The series of interactions leading to Gandhara art occurred over time, beginning with Alexander the Great's brief incursion into the area, followed by the Mauryan Emperor Ashoka converting the region to Buddhism. Buddhism became the prominent religion in the Indo-Greek Kingdoms. However, Greco-Buddhist art truly flowered and spread under the Kushan Empire, when the first surviving devotional images of the Buddha were created during the 1st-3rd centuries CE. Gandhara art reached its zenith from the 3rd-5th century CE, when most surviving motifs and artworks were produced.

Gandhara art is characterized by Buddhist subject matter, sometimes adapting Greco-Roman elements, rendered in a style and forms that are heavily influenced by Greco-Roman art. It has the strong idealistic realism and sensuous description of Hellenistic art, and it is believed to have produced the first representations of Gautama Buddha in human form, ending the early period of aniconism in Buddhism.

The representation of the human form in large sculpture had a considerable influence, both to the south in the rest of India, and to the east, where the spread of Buddhism carried its influence as far as Japan.