The First Opium War known as the Opium War or the Anglo-Chinese War, was a series of military engagements fought between Great Britain and the Qing dynasty of China. The immediate issue was Chinese official seizure of opium stocks at Canton to stop the banned opium trade, threatening the death penalty for future offenders; the British government insisted on the principles of free trade and equality among nations and backed the merchants' demands. The British Navy defeated the Chinese using technologically superior ships and weapons, the British imposed a treaty that granted territory to Western powers and opened trade with China; the conflict had been building for decades. In the 18th century the demand for Chinese luxury goods created a trade imbalance between China and Britain. European silver flowed into China through the Canton System, which confined incoming foreign trade to the southern port city of Canton. To counter this imbalance, the British East India Company began to grow opium in Bengal, in present-day Bangladesh, allowed private British merchants to sell opium to Chinese smugglers for illegal sale in China.

The influx of narcotics reversed the Chinese trade surplus, drained the economy of silver, increased the numbers of opium addicts inside the country, outcomes that worried Chinese officials. In 1839, the Daoguang Emperor, rejecting proposals to legalize and tax opium, appointed viceroy Lin Zexu to go to Canton to halt the opium trade completely. Lin wrote to Queen Victoria an open letter in an appeal to her moral responsibility to stop the opium trade, but it was never delivered; when he failed to get a response, Lin attempted to get foreign companies to forfeit their opium stores in exchange for tea, but this failed too. Lin resorted to using force in the western merchants' enclave, he confiscated all supplies and ordered a blockade of foreign ships to get them to surrender their opium supply. Lin confiscated 20,283 chests of opium; the British government responded by dispatching a military force to China and in the ensuing conflict, the Royal Navy used its naval and gunnery power to inflict a series of decisive defeats on the Chinese Empire, a tactic referred to as gunboat diplomacy.

In 1842, the Qing dynasty was forced to sign the Treaty of Nanking—the first of what the Chinese called the unequal treaties—which granted an indemnity and extraterritoriality to foreigners in China, opened five treaty ports to foreign merchants, ceded Hong Kong Island to the British Empire. The failure of the treaty to satisfy British goals of improved trade and diplomatic relations led to the Second Opium War; the following social unrest within China was the background for the Taiping Rebellion, which further weakened the dynasty. In China, the year 1849 is considered the beginning of modern Chinese history. Direct maritime trade between Europe and China began in 1557 when the Portuguese leased an outpost from the Ming dynasty at Macau. Other European nations soon followed the Portuguese lead, inserting themselves into the existing Asian maritime trade network to compete with Arab, Chinese and Japanese merchants in intra-regional commerce. After the Spanish conquest of the Philippines the exchange of goods between China and Europe accelerated dramatically.

From 1565 on, the Manila Galleons brought silver into the Asian trade network from mines in South America. China was a primary destination for the precious metal, as the imperial government mandated that Chinese goods could only be exported in exchange for silver bullion. British ships began to appear sporadically around the coasts of China from 1635 on. Without establishing formal relations through the Chinese tributary system, by which most Asian nations were able to negotiate with China, British merchants were only allowed to trade at the ports of Zhoushan and Guangzhou. Official British trade was conducted through the auspices of the British East India Company, which held a royal charter for trade with the Far East; the East India Company came to dominate Sino-European trade from its position in India and due to the strength of the Royal Navy. Trade benefited. Taiwan came under Qing control in 1683 and rhetoric regarding the tributary status of Europeans was muted. Guangzhou became the port of preference for incoming foreign trade.

Ships did try to call at other ports, but these locations could not match the benefits of Canton's geographic position at the mouth of the Pearl River, nor did they have the city's long experience in balancing the demands of Beijing with those of Chinese and foreign merchants. From 1700 onward Canton was the center of maritime trade with China, this market process was formulated by Qing authorities into the "Canton System". From the system's inception in 1757, trading in China was lucrative for European and Chinese merchants alike as goods such as tea and silk were valued enough in Europe to justify the expenses of traveling to Asia; the system was regulated by the Qing government. Foreign traders were only permitted to do business through a body of Chinese merchants known as the Cohong and were forbidden to learn Chinese. Foreigners could only live in one of the Thirteen Factories and were not allowed to enter or trade in any other part of China. Only low level government officials could be dealt with, the imperial court could not be lobbied for any reason excepting official diplomatic missions.

The Imperial laws that upheld the system were collectively known as the Prevention Barbarian Ordinances

In the geometry of hyperbolic 3-space, the order-6-4 triangular honeycomb is a regular space-filling tessellation with Schläfli symbol. It has four triangular tiling around each edge. All vertices are ultra-ideal with infinitely many triangular tilings existing around each vertex in an order-4 hexagonal tiling vertex arrangement, it has a second construction as a uniform honeycomb, Schläfli symbol, Coxeter diagram, with alternating types or colors of triangular tiling cells. In Coxeter notation the half symmetry is =, it a part of a sequence of regular polychora and honeycombs with triangular tiling cells: In the geometry of hyperbolic 3-space, the order-6-3 triangular honeycomb is a regular space-filling tessellation with Schläfli symbol. It has five triangular tiling, around each edge. All vertices are ultra-ideal with infinitely many triangular tilings existing around each vertex in an order-5 hexagonal tiling vertex arrangement. In the geometry of hyperbolic 3-space, the order-6-6 triangular honeycomb is a regular space-filling tessellation with Schläfli symbol.

It has infinitely many triangular tiling, around each edge. All vertices are ultra-ideal with infinitely many triangular tilings existing around each vertex in an order-6 triangular tiling vertex arrangement, it has a second construction as a uniform honeycomb, Schläfli symbol, Coxeter diagram, =, with alternating types or colors of triangular tiling cells. In Coxeter notation the half symmetry is =. In the geometry of hyperbolic 3-space, the order-6-infinite triangular honeycomb is a regular space-filling tessellation with Schläfli symbol, it has infinitely many triangular tiling, around each edge. All vertices are ultra-ideal with infinitely many triangular tilings existing around each vertex in an infinite-order triangular tiling vertex arrangement, it has a second construction as a uniform honeycomb, Schläfli symbol, Coxeter diagram, =, with alternating types or colors of triangular tiling cells. In Coxeter notation the half symmetry is =. Convex uniform honeycombs in hyperbolic space List of regular polytopes Coxeter, Regular Polytopes, 3rd.

Ed. Dover Publications, 1973. ISBN 0-486-61480-8; the Beauty of Geometry: Twelve Essays, Dover Publications, LCCN 99-35678, ISBN 0-486-40919-8 Table III Jeffrey R. Weeks The Shape of Space, 2nd edition ISBN 0-8247-0709-5 George Maxwell, Sphere Packings and Hyperbolic Reflection Groups, JOURNAL OF ALGEBRA 79,78-97 Hao Chen, Jean-Philippe Labbé, Lorentzian Coxeter groups and Boyd-Maxwell ball packings, Visualizing Hyperbolic Honeycombs arXiv:1511.02851 Roice Nelson, Henry Segerman Spherical Video: honeycomb with parabolic Möbius transform YouTube, Roice Nelson John Baez, Visual insights: Honeycomb Honeycomb Meets Plane at Infinity Danny Calegari, Kleinian, a tool for visualizing Kleinian groups and the Imagination 4 March 2014

The Convair XF-92 was an early American delta wing aircraft. Conceived as a point-defence interceptor, the design was used purely for experimental purposes. However, it led Convair to use the delta-wing on a number of designs, including the F-102 Delta Dagger, F-106 Delta Dart, B-58 Hustler, the US Navy's F2Y Sea Dart as well as the VTOL FY Pogo. Prior to August 1945, the Vultee Division of Consolidated-Vultee looked at the possibility of a swept-wing aircraft powered by a ducted rocket. Years earlier, the company had performed designs. With this design, fuel would be added to the heat produced by small rocket engines in the duct, creating a "pseudo-ramjet". In August 1945, the United States Army Air Forces, soon to be renamed the United States Air Force, issued a proposal for a supersonic interceptor capable of 700 mph speeds and reaching an altitude of 50,000 feet in four minutes. Several companies responded, among, Consolidated-Vultee, which submitted its design on 13 October 1945; this design featured swept V-tails, as well as a powerful propulsion system.

Besides the ducted rocket, four 1,200 pounds-force rockets were positioned at the exhaust nozzle, along with the 1,560 pounds-force 19XB turbojet produced by Westinghouse. A proposal by Consolidated Vultee was accepted in May 1946, with a proposal for a ramjet-powered aircraft, with a 45° swept wing under USAAF Air Materiel Command Secret Project MX-813. However, wind tunnel testing demonstrated a number of problems with this design; as part of Operation Paperclip and similar efforts, Alexander Lippisch's DM1 research glider had been completed and shipped to the National Advisory Committee for Aeronautics Langley Research Center, along with considerable German research on swept wings and delta wings. The DM1 was the first in a planned series of four similar testbed aircraft, each one exploring faster speeds; the DM1 was built to test low-speed handling only. At Langley, the thick-section airfoils of the DM1 were found to generate considerable drag at transonic speeds, a series of experiments followed to try to explore these issues.

Two lines of study were considered. This left considerable room in front of the stabilizer. During these tests, the tendency for the wings to generate large vortices at high angles of attack was noticed, but the significance of this was not exploited until many years later. Langley passed along the delta wing information to Convair designers Adolph Burstein, the assistant chief engineer of the San Diego Division, Ralph Shick, chief of aerodynamic research; the two were sceptical of the delta wing, but Shick flew to meet Lippisch at Wright-Patterson Air Force Base and returned to Convair's Downey plant convinced this was the way to move forward. Convair's mixed propulsion system required a large air duct to the engine, which supplied not only the jet engine with air, but acted as a supply to the rockets to produce thrust augmentation; this left nowhere to put a traditional cockpit. To address this, the team modified the design in a fashion similar to both the Leduc 0.10 and Miles M.52, placing the cockpit in a cylindrical body in the center of the intake.

Power was provided by the 1,560 lbf Westinghouse J30 assisted by a battery of six 2,000 lbf liquid-fueled rockets. The design was presented to the U. S. Air Force in 1946, was accepted for development as the XP-92. In order to gain inflight experience with the delta wing layout, Convair suggested building a smaller prototype, the Model 7002, which the USAAF accepted in November 1946; the design was similar to Langley's modifications to the DM1, using the smaller vertical surface, thinner wings, a conventional cockpit. The main difference was to the stretch the fuselage rearward to provide room for the engine, leading to a conventional fuselage shape. In order to save development time and money, many components were taken from other aircraft. Construction was well underway at Vultee Field in Downey, California when North American Aviation took over the Vultee plants in summer 1947; the airframe was moved to Convair's plant in San Diego, completed in the autumn. In December it was shipped without an engine to NACA's Ames Aeronautical Laboratory for wind tunnel testing.

After testing was completed, the airframe was returned to San Diego, where it was fitted with a 4,250 lbf Allison J33-A-21 engine. By the time the aircraft was ready for testing, the concept of the point-defense interceptor seemed outdated and the F-92 project was cancelled, they decided to rename the test aircraft as the XF-92A. In April 1948 the XF-92A was shipped to Muroc Dry Lake. Early tests were limited to taxiing, although a short hop was made on 9 June 1948; the XF-92A's first flight was on 18 September 1948 with Convair test pilot Ellis D. "Sam" Shannon at the controls. On 21 December 1948 Bill Martin began testing the aircraft for the company. After 47 flights totaling 20 hours and 33 minutes, the aircraft was turned over to the USAAF on 26 August 1949, with the testing being assigned to Frank Everest and Chuck Ye