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The Artificio de Juanelo ("Gianello's artifice") was the name of two devices built in Toledo in the 16th century by Juanelo Turriano. They were designed to supply the city with a source of readily available water by lifting it from the Tagus (Tajo) river to the Alcázar. Now in ruins, the precise details of the operation of the devices are unknown, but at the time they were considered engineering wonders.

Millipede memory is a form of non-volatile computer memory. It promised a data density of more than 1 terabit per square inch (1 gigabit per square millimeter), which is about the limit of the perpendicular recording hard drives. Millipede storage technology was pursued as a potential replacement for magnetic recording in hard drives and a means of reducing the physical size of the technology to that of flash media.

IBM demonstrated a prototype millipede storage device at CeBIT 2005, and was trying to make the technology commercially available by the end of 2007. However, because of concurrent advances in competing storage technologies, no commercial product has been made available since then.

The Mulford Act was a 1967 California bill that repealed a law allowing public carrying of loaded firearms. Named after Republican assemblyman Don Mulford, and signed into law by governor of California Ronald Reagan, the bill was crafted with the goal of disarming members of the Black Panther Party who were conducting armed patrols of Oakland neighborhoods, in what would later be termed copwatching. They garnered national attention after Black Panthers members, bearing arms, marched upon the California State Capitol to protest the bill.

Assembly Bill 1591 was introduced by Don Mulford (R) from Oakland on April 5, 1967, and subsequently co-sponsored by John T. Knox (D) from Richmond, Walter J. Karabian (D) from Monterey Park, Frank Murphy Jr. (R) from Santa Cruz, Alan Sieroty (D) from Los Angeles, and William M. Ketchum (R) from Bakersfield. AB-1591 was made an “urgency statute” under Article IV, §8(d) of the Constitution of California after “an organized band of men armed with loaded firearms [...] entered the Capitol” on May 2, 1967; as such, it required a 2/3 majority in each house. It passed the Assembly (controlled by Democrats, 42:38) at subsequent readings, passed the Senate (controlled by Democrats, 20:19) on July 26 by 29 votes to 7, and was signed by Governor Ronald Reagan on July 28, 1967. The law banned the carrying of loaded weapons in public.

Both Republicans and Democrats in California supported increased gun control, as did the National Rifle Association of America. Governor Ronald Reagan, who was coincidentally present on the capitol lawn when the protesters arrived, later commented that he saw "no reason why on the street today a citizen should be carrying loaded weapons" and that guns were a "ridiculous way to solve problems that have to be solved among people of good will." In a later press conference, Reagan added that the Mulford Act "would work no hardship on the honest citizen."

The bill was signed by Reagan and became California penal code 25850 and 171c.

Lloyd's Coffee House was a significant meeting place in London in the 17th and 18th centuries.

It was opened by Edward Lloyd (c. 1648–15 February 1713) on Tower Street in 1686. The establishment was a popular place for sailors, merchants and shipowners, and Lloyd catered to them by providing reliable shipping news. The shipping industry community frequented the place to discuss maritime insurance, shipbroking and foreign trade. The dealings that took place led to the establishment of the insurance market Lloyd's of London, Lloyd's Register and several related shipping and insurance businesses.

The coffee shop relocated to Lombard Street in December 1691. Lloyd had a pulpit installed in the new premises, from which maritime auction prices and shipping news were announced. Candle auctions were held in the establishment, with lots frequently involving ships and shipping. From 1696–1697 Lloyd also experimented with publishing a newspaper, Lloyd's News, reporting on shipping schedules and insurance agreements reached in the coffee house. In 1713, the year of Edward Lloyd's death, he modified his will to assign the lease of the coffee house to his head waiter, William Newton, who then married one of Lloyd's daughters, Handy. Newton died the following year and Handy subsequently married Samuel Sheppard. She died in 1720 and Sheppard died in 1727, leaving the coffee house to his sister Elizabeth and her husband, Thomas Jemson. Jemson founded the Lloyd's List newspaper in 1734, similar to the previous Lloyd's News. Merchants continued to discuss insurance matters here until 1774, when the participating members of the insurance arrangement formed a committee and moved to the Royal Exchange on Cornhill as the Society of Lloyd's.

The Tunnel of Eupalinos or Eupalinian aqueduct (Greek: Ευπαλίνιον όρυγμα, romanized: Efpalinion orygma) is a tunnel of 1,036 m (3,399 ft) length running through Mount Kastro in Samos, Greece, built in the 6th century BC to serve as an aqueduct. The tunnel is the second known tunnel in history which was excavated from both ends (Ancient Greek: ἀμφίστομον, romanized: amphistomon, "having two openings"), and the first with a geometry-based approach in doing so. Today it is a popular tourist attraction.

A dark fibre or unlit fibre is an unused optical fibre, available for use in fibre-optic communication. Dark fibre may be leased from a network service provider.

Dark fibre originally referred to the potential network capacity of telecommunication infrastructure. Because the marginal cost of installing additional fibre optic cables is very low once a trench has been dug or conduit laid, a great excess of fibre was installed in the US during the telecom boom of the late 1990s and early 2000s. This excess capacity was later referred to as dark fibre following the dot-com crash of the early 2000s that briefly reduced demand for high-speed data transmission.

These unused fibre optic cables later created a new market for unique private services that could not be accommodated on lit fibre cables (i.e., cables used in traditional long-distance communication).

Petrodollar recycling is the international spending or investment of a country's revenues from petroleum exports ("petrodollars"). It generally refers to the phenomenon of major petroleum-exporting nations, mainly the OPEC members plus Russia and Norway, earning more money from the export of crude oil than they could efficiently invest in their own economies. The resulting global interdependencies and financial flows, from oil producers back to oil consumers, can reach a scale of hundreds of billions of US dollars per year – including a wide range of transactions in a variety of currencies, some pegged to the US dollar and some not. These flows are heavily influenced by government-level decisions regarding international investment and aid, with important consequences for both global finance and petroleum politics. The phenomenon is most pronounced during periods when the price of oil is historically high.

The term petrodollar was coined in the early 1970s during the oil crisis, and the first major petrodollar surge (1974–1981) resulted in more financial complications than the second (2005–2014).

In August 2018, Venezuela declared that it would price its oil in Euros, Yuan and other currencies.

The traditional Burmese units of measurement as of 2010 were still in everyday use in Myanmar (also known as Burma). According to the 2010 CIA Factbook, Myanmar is one of three countries that have not adopted the International System of Units (SI) metric system as their official system of weights and measures. However, in June 2011, the Burmese government's Ministry of Commerce began discussing proposals to reform the measurement system in Burma and adopt the metric system used by most of its trading partners, and in October 2013, Dr. Pwint San, Deputy Minister for Commerce, announced that the country was preparing to adopt the metric system.

Most of the nation uses Burmese units only, although Burmese government web pages in English use imperial and metric units inconsistently. For instance, the Ministry of Construction uses miles to describe the length of roads and square feet for the size of houses, but square kilometres for the total land area of new town developments in Yangon City. The Ministry of Agriculture uses acres for land areas. The Ministry of Foreign Affairs uses kilometres (with mile equivalents in parentheses) to describe the dimensions of the country.

Demand Progress is an internet activist-related entity encompassing a 501(c)4 arm sponsored by the 1630 Fund and a 501(c)3 arm sponsored by the New Venture Fund. It specializes in online-intensive and other grassroots activism to support Internet freedom, civil liberties, transparency, and human rights, and in opposition to censorship and corporate control of government. The organization was founded through a petition in opposition to the Combating Online Infringement and Counterfeits Act, sparking the movement that eventually defeated COICA's successor bills, the Stop Online Piracy Act and the PROTECT IP Act, two highly controversial pieces of United States legislation.

The organization has continued to fight for such causes in the wake of the successful shelving of these two acts. Demand Progress has also played key roles in forwarding the passage of net neutrality rules, blocking expansion of the Computer Fraud and Abuse Act, under which co-founder Aaron Swartz was indicted, and other key legislative efforts. Estimated membership numbers in early 2015 weigh in at over two million. As of late 2013, the organization encompasses the Demand Progress, Rootstrikers and Watchdog.net wings/brands.

This is a list of paradoxes, grouped thematically. The grouping is approximate, as paradoxes may fit into more than one category. This list collects only scenarios that have been called a paradox by at least one source and have their own article. Although considered paradoxes, some of these are simply based on fallacious reasoning (falsidical), or an unintuitive solution (veridical). Informally, the term paradox is often used to describe a counter-intuitive result.

However, some of these paradoxes qualify to fit into the mainstream perception of a paradox, which is a self-contradictory result gained even while properly applying accepted ways of reasoning. These paradoxes, often called antinomy, point out genuine problems in our understanding of the ideas of truth and description.