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MY'STORY

The MOVE Fire

This is a personal recollection on the Move fire on May 13, 1985 Philadelphia police fired thousands of rounds at the MOVE house, city officials approved dropping an explosive device on the roof, the resulting fire was allowed to burn, 11 people—including five children—died, and 61 homes were destroyed. Philadelphia City Council later called it a “brutal attack carried out by the City of Philadelphia on its own citizens” and acknowledged that no individual faced criminal consequences for the bombing. One timeline correction worth preserving for the BHP record: the major previous MOVE-police confrontation was August 8, 1978, about seven years before the bombing, not a year or two earlier. Officer James Ramp was killed, other police and firefighters were wounded, nine MOVE members were later convicted, and television cameras recorded police beating Delbert Africa during his arrest. The 1985 MOVE Commission later specifically criticized city planners for failing to adequately use lessons from that 1978 confrontation. And that actually strengthens the point you’re making: 1985 did not happen without precedent or institutional memory. There had already been a deadly confrontation with MOVE, years of conflict, negotiations and police involvement before Osage Avenue.

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BLACK FACTS
The Truths They Never Taught You...

Katherine Johnson — Mathematics to the Moon

Katherine Johnson’s mathematical calculations helped guide some of America’s most important early space missions while she confronted the racial and gender barriers faced by Black women in twentieth-century America.

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BHP gathered finds from its connected research sources. Showing the 4 strongest Black History matches.
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Wikipedia

Monofin

A freediver using a monofin
Herbert Nitsch wearing a monofin at the Cyprus BIOS 2004 Freediving Open Classic

A monofin is a type of swimfin typically used in underwater sports such as finswimming, free-diving and underwater orienteering. It consists of a single or linked surfaces attached to both of the diver's feet, emulating the fluke of Cetaceans like whales or porpoises. Even though the diver's appearance might be reminiscent of a mermaid or merman, monofin swimming is not the same as mermaiding.

The arrival of the monofin in the early 1970s led to the breaking of all finswimming world records by the end of the decade due to the improved performance possible when used instead of two ordinary swimfins.[1][better source needed]

Use

[edit]

To differentiate between the use of monofins and conventional fins, the latter are sometimes referred to as stereo fins or bi-fins.

The monofin swimmer extends arms forward, locking hands together, locking the head between the biceps, in a position known as streamline position. The undulating movement starts in the shoulders, with maximum amplitude towards the hips; the legs almost don't bend to transfer the movement to the monofin. This technique is called the dolphin kick.

By slowly oscillating the surface of the monofin when submerged, divers can generate large amounts of thrust even with small or slow movements. This preserves energy which helps when breathholding (apnea).

Monofin kick tempo doesn't have to be slow. In 100 m surface swimming, tempo is around 2 kicks per second.[2]

Separate from its functional use in swimming or diving, monofins may be used ornamentally, as part of a mermaid costume.

History

[edit]
Monofin made in 1969 by Franco Pavone in Bologna

1949: Kurt Schaefer,[3] who invented an underwater film camera during wartime military service in Italy, designs a pair of homemade swimming fins, which he proceeds to fasten together with straps and cords to create what is probably the world's first monofin.[4][5] The artefact is on display in the Aquazoo-Löbbecke Museum in the German city of Düsseldorf.

1955: On 19 September 1955, Kurt Ristau and Hans Joachim Bergann, who founded the underwater diving equipment manufacturing company Barakuda in the early 1950s in the German city of Hamburg after serving as combat swimmers during World War II, file a patent for a monofin-like device for swimmers incorporating both feet. Although the invention receives German patent 1085798 on 12 January 1961,[6] it never enters the production stage.

1962: On 15 October 1962, James S Christiansen files a patent for a device enabling a pair of swimming fins to be coupled together to reduce fatigue and cramping during prolonged swimming. Although the detachable coupling converting the separate swimming fins into a monofin-like design is granted US patent 3165764A[7] on 19 January 1965, it does not appear to have entered the production stage.

1967: In his review of the range of fins available in France during that year, J. Larue[8] mentions how unnamed experts are experimenting with the use of a single swim fin accommodating both feet of the swimmer, who deploys the butterfly stroke to progress in the water. Although the experiment yields relatively satisfactory results for swimmers, Larue concludes that this fin is unsuitable for divers.

1969: Franco Pavone[9] constructs his "Matrimoniale" monofin in the Italian city of Bologna. After designing a high-speed monofin with a metal-reinforced rubber blade, Boris Porotov[10] (Kazakh Soviet Socialist Republic) builds an entire blade out of fibreglass-reinforced plastic.[11][12]

1970: On 10 December 1970, Spanish underwater diving equipment company Nemrod-Metzeler[13] patents a monofin-like device for swimmers incorporating both feet, but it never enters production.

1971: Nadejda Turukalo (USSR) arrives at European Finswimming Championship (1970, Barcelona, Spain) with a monofin constructed from two titanium branches, joined by a "sail".[14] She beats all comers. Monofins have been used ever since for finswimming competitions, allowing monofin swimmers to reach speeds of 12 km/h.[15] Traditional monofin 50 m apnea world record is as fast as 13 km/h.

Construction

[edit]
Monofin
All-rubber monofin for pool workouts with other swimmers present and for younger swimmers with growing feet

Monofins can be made of glass fiber, carbon fiber, or aluminum, and rubber. The diver's muscle power, swimming style, and the type of aquatic activity the monofin is used for determine the choice of size, stiffness, and materials.

Most monofins consist of a single, wide, glass or carbon fiber reinforced composite blade with graded flexibility, attached to the diver by two rubber foot pockets. The leading edge may be thickened and faired. The blade flexibility is generally controlled by tapering the amount of fibre and thickness of the blade to make the trailing edge thinner and more flexible.

See also

[edit]
  • Mermaiding – Swimming dressed in a mermaid costume

References

[edit]
  1. ^ "Finswimming". Official site dedicated to Luigi Ferraro. Retrieved 3 December 2013.
  2. ^ Men's 100 m Fin Swimming Surface Final | Underwater Swimming | Baku 2015 European Games, retrieved 2021-06-14
  3. ^ International Scuba Diver Hall of Fame: Kurt Schaefer (Austria). Retrieved on 5 February 2019.
  4. ^ Kurt Schaefer (2015) "Kurt Schaefer - meine Geschichte", Tauchhistorie 2015:03, pp. 59-63. Retrieved on 5 February 2019.
  5. ^ Rossella Paternò (2018) "Kurt Schaefer, un grande pioniere della fotografia subacquea", HDS Notizie N. 64: March 2018, pp. 9-20. Retrieved on 11 November 2019.
  6. ^ Johannes Kreutzmann, Dr Kurt Ristau and Hans Joachim Bergann (1961) Gleichzeitig von beiden Füßen eines Schwimmenden zu betätigender Schwimmhilfskörper. German Patent Office. Retrieved on 5 February 2019.
  7. ^ James S Christiansen (1965) Detachable coupling for swimming fin United States Patent and Trademark Office. Retrieved on 5 February 2019.
  8. ^ J. Larue (1967) "PALMORAMA", plongées No. 34. Retrieved on 15 August 2020.
  9. ^ "Franco Pavone, il gamma". Apnea Magazine. 16 March 2006. Retrieved 18 July 2019.
  10. ^ International Scuba Diver Hall of Fame: Boris Poratov (Kazakhstan, USSR). Retrieved on 5 February 2019.
  11. ^ Tomsk State University: История ластов. Retrieved on 5 February 2019.
  12. ^ Boris Poratov (1971) "Освоение нового стиля плавания", Спортсмен-подводник 1971:28, pp. 8-12. Retrieved on 15 April 2019.
  13. ^ Nemrod-Metzeler: Nueva aleta común para la natación. Retrieved on 5 February 2019.
  14. ^ "Finswimming: European Championships 1967-2001".
  15. ^ "Dolphin-Inspired Man-Made Fin Works Swimmingly". Scientific American. Retrieved 17 Sep 2016.
[edit]

Source: Wikipedia. Article content is retrieved live through the MediaWiki API.

Wikipedia

Monofin

A monofin is a type of swimfin typically used in underwater sports such as finswimming, free-diving and underwater orienteering. It consists of a single or linked surfaces attached to both of the diver's feet, emulating the fluke of Cetaceans like whales or porpoises. Even though the diver's appearance might be reminiscent of a mermaid or merman, monofin swimming is not the same as mermaiding. The arrival of the monofin in the early 1970s led to the breaking of all finswimming world records by the end of the decade due to the improved performance possible when used instead of two ordinary swimfins.

MORE →
Wikipedia

Finswimming

Finswimming is an underwater sport consisting of four techniques involving swimming with the use of fins either on the water's surface using a snorkel with either monofins or bifins or underwater with monofin either by holding one's breath or using open circuit scuba diving equipment. Events exist over distances similar to swimming competitions for both swimming pool and open water venues. Competition at world and continental level is organised by the Confédération Mondiale des Activités Subaquatiques (CMAS, World Underwater Federation). The sport's first world championship was held in 1976. It also has been featured at the World Games as a trend sport since 1981 and was demonstrated at the 2015 European Games in June 2015.

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Wikipedia

Constant weight apnea

Constant weight (CWT) is a freediving discipline recognised by AIDA, the International Association for the Development of Apnea, in which the freediver descends and ascends using their monofin and/or with the use of their arms without pulling on the rope or changing their ballast; only a single hold of the rope to stop the descent and start the ascent is allowed. Constant weight is one of the eight disciplines considered for international competition, the others being constant weight bi-fins (CWTB), constant weight without fins (CNF), static apnea (STA), dynamic apnea without fins (DNF), dynamic with fins (DYN), free immersion (FIM), and dynamic apnea bi-fins (DYNB).

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Wikipedia

List of British records in finswimming

Below is the list of current British records in finswimming. The records are ratified by the British Finswimming Association. This list echoes that found on the Monofin website. These records are correct as of 1 April 2018. In December 2017 British Finswimming Association made a decision to maintain the National records separately for adults and juniors in line with CMAS regulations.

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TOPIC OF THE DAY

Greenwood / Black Wall Street

Before the 1921 destruction of Tulsa’s Greenwood District, Black residents had created a remarkable center of business and community life. The district included stores, professional offices, entertainment venues and homes owned by Black citizens. Understanding Greenwood means learning what was built—not only what was burned.

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TRIVIA QUESTION OF THE DAY

Who became the first Black woman to travel into space?

Mae Jemison, aboard Space Shuttle Endeavour in 1992.