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Flights of Fancy The “1001 Inventions” Exhibition and Popular Misrepresentations of Medieval Muslim Science and Technology Taner Edis Department of Physics Truman State University

Flights of Fancy The “1001 Inventions” Exhibition and Popular Misrepresentations of Medieval Muslim Science and Technology Taner Edis Department of Physics

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Flights of FancyThe “1001 Inventions” Exhibition and

Popular Misrepresentations of Medieval Muslim Science and Technology

Taner EdisDepartment of Physics Truman State University

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1001 Inventions

• Exhibit (London, New York, Abu Dhabi, Los Angeles, Istanbul, Washington DC, . . .) and catalog.

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“Flight” in 1001 Inventions

• “The first Muslim, and perhaps person, to make a real attempt to construct a flying machine and fly was Cordoban ’Abbas Ibn Firnas in the ninth century. . . his greatest fame was for constructing a flying machine, the first of its kind capable of carrying a human into the air. He flew successfully a number of times over desert regions . . .” (p. 296)

• A “flight machine” made from “silk and eagle feathers.”

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Powered flight?

• “In the Rusafa area on the outskirts of Córdoba, Ibn Firnas mounted a hill and appeared before the crowd in his bird costume, made from silk covered with eagle feathers, which he tightened with fine strips of silk. Ibn Firnas explained with a piece of paper how he planned to fly using the wings fitted on his arms: ‘Presently, I shall take leave of you. By guiding these wings up and down, I should ascend like the birds. If all goes well, after soaring for a time I should be able to return safely to your side.’”

• The catalog later mentions a “later version” of Ibn Firnas’s flying machine, likened to an ornithopter—also implying powered flight. Others, e.g. Jamsari et al. 2013.

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Birds landing peculiarly

• “He flew to a significant height and hung in the air for more than ten minutes before plummeting to the ground, breaking the wings and one of his vertebrae. After the event, Ibn Firnas understood the role played by the tail, telling his close friends that when birds land, they normally land on the root of the tail, which did not happen for him because he did not have one.”

• “All modern airplanes land on their rear wheels first, which makes Ibn Firnas’s comment ahead of its time.” (p. 297)

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Hezarfen Ahmet Çelebi

• “. . . used eagle feathers stitched to his wings to fly. After nine experimental attempts, he finally decided on the shape of his wings. His most famous flight took place in 1638 from the Galata tower near the Bosporus in Istanbul, and he successfully landed on the other side of the strait.” (p. 299)

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Muslims at the roots of flight

• “All this history of aviation, and even space travel, started with humble beginnings of one man, ’Abbas Ibn Firnas, who was one of the first to try out his ideas when he glided with his eagle feathers and silk” (p. 300). The history of aviation is a line of progress building on the initial achievements of Ibn Firnas.

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Pop culture Ibn Firnas

• Philatelic site: “Libya, MNH, Airplane Aviation 1978. 75th Ann of the 1st Powered Flight (abbas ibn firnas)”

• Ibn Firnas statue in Baghdad; an airport in Baghdad.

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Pop culture Hezarfen Ahmet

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Movie, university book, textbook. Note implicit powered flight.

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Al-Makkari, 7 centuries later

• “. . . Among other very curious experiments which [Ibn Firnas] made, one is his trying to fly. He covered himself with feathers for the purpose, attached a couple of wings to his body, and, getting on an eminence, flung himself down into the air, when according to the testimony of several trustworthy writers who witnessed the performance, he flew a considerable distance, as if he had been a bird, but, in alighting again on the place whence he had started, his back was very much hurt, for not knowing that birds when they alight come down upon their tails, he forgot to provide himself with one. Múmen Ibn Sa’id has said, in a verse alluding to this extraordinary man, ‘He flew faster than the phoenix in his flight when he dressed his body in the feathers of a vulture.’”

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Details dubious

• “Although ‘Abbas b. Firnas may have managed to glide for some distance, he cannot have alighted again ‘on the place whence he started’, as this would imply that he was able to sustain himself at a constant height in the air”; “Al-Makkari’s comment on the function of the tail is absurd, and may have been garbled in transmission” (Clive Hart 1972).

• “. . . it is in all likelihood more accurate to envision him sinking earthwards at a high—though fortunately not terminal— rate of descent rather than gently settling downwards in a true glide” (Hallion (Richard P. Hallion 2003).

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Evliya Çelebi, 17th century

• “At first he practiced by flying over the pulpit of Okmeydanı eight or nine times with eagle wings, using the force of the wind. Then, as Sultan Murad Khan (Murad IV) was watching from the Sinan Pasha mansion at Sarayburnu, he flew from the very top of the Galata Tower and fell on the Doğancılar Square in Üsküdar, with the help of the south-west wind. Then Murad Khan granted Hezarfen Ahmet Çelebi a sack of golden coins, and said: ‘This is a scary man. He is capable of doing anything he wishes. It is not right to keep such people,’ and thus sent him to Algeria on exile. He died there.”

• Evliya Çelebi writes closer in time to the events (1630s?).

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Unreliable source

• Much that is related in Evliya Çelebi’s Seyahatname is poorly transmitted hearsay; the book includes material that is implausible, occasionally clearly fictional, or exaggerated to improve the story.

• HAÇ flight: a singular tale of wonder, with no indication of context, and nothing similar preceding or following the event described.

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Forces: ornithopter

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ThrustDrag

Velocity

Lift

Weight

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Scaling

• Unless density is reduced, weight is proportional to volume: (length)3

• Lift forces and muscle power are proportional to area: (length)2

• Humans are too dense, and our muscles distributed wrongly to fly ornithopter-style.

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Powered flight

• Biologically: low density, immense wing span. Quetzalcoatlus.

• Technologically: advanced materials, leg muscles. Gossamer Condor.

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Forces: gliding

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Drag

Velocity

Lift

Weight

a

b a:b = “glide ratio”

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Hezarfen glide ratio 45:1

• Modern hang gliders: around 20:1

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Making Hezarfen Ahmet fly

• Updrafts for lift: wrong geography.

• Wind in opposite direction of account. ~Kite effect, as in 6th century Chinese accounts. Very dangerous; implausible.

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Flight in 1001 Inventions

• Physically implausible accounts with poor historical evidence.

• Narrative of technological progress built on foundation of alleged Muslim “firsts”—but outside mainstream of historical development.

• Consultant historians and engineers should have noticed obvious problems.

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Why the mistakes?

• “Much of the material for this book is based on peer-reviewed papers, articles, and presentations published on our academic portal, www.MuslimHeritage.com” (p. 351)

• “The 1001 Inventions project has proved its effectiveness to stimulate young people’s interest in science and technology, to instil confidence, and to provide positive Muslim role models for evolving Muslim identities, especially in the West.” (2nd ed., p. 2)

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For Muslim self-esteem?

• Muslim populations do lag in basic science production, and harbor strong religion-associated pseudoscientific beliefs such as creationism. (Better in applied science.)

• Narrative of 1001 Inventions driven by needs for technological catching-up and cultural defense. Common themes: complete harmony between Islam and science; Islam led science and technology back when religion was purer…

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Revive or start over?

• Linked to common calls to revive a Muslim Golden Age.

• Modern science is different. Can’t improve Muslim standing by reviving medieval habits of thought.

• It is not clear that efforts like 1001 Inventions, though well-intentioned, help Muslim participation in or perception of modern science.

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