Alexander Graham Bell built giant tetrahedral kites because their shape shares joints and spars
the gist
Alexander Graham Bell, best known for the telephone, spent years experimenting with aerodynamics. He was drawn to the tetrahedron, a pyramid-shaped structure, because its cells can share joints and spars. That makes the frame strong while keeping the weight low for the area it covers. Bell began with small tetrahedral box kites in 1898 and later built large compound kites called Cygnet I, II and III, meant to carry a person into the air. Some were flown unmanned and manned in the years up to 1912.
how it works
A tetrahedron has four triangular faces, and triangles hold their shape without bending. Joining several tetrahedra shares their edges, so the frame stays stiff while using little material. That combination of strength and low weight is what made the design attractive for lifting people.
so what
Tetrahedral frames are still used in lightweight engineering, from space structures to geodesic domes, because they are rigid without much material. Bell's kites show early work on using light structures to lift heavy loads.
In 1909 D. W. Griffith made a 14-minute film about a speculator who corners the wheat market and doubles the price of bread. A farmer sows his field while a 'Wheat King' gambles in the Chicago wheat pit; bakers raise the loaf from five cents to ten and the poor line up for bread. Griffith cut back and forth between the farm, the feast and the breadline, a technique called parallel editing, so audiences saw both ends of the economy at once. The film drew on Frank Norris's stories and on a real scheme: months earlier Chicago financier James Patten had cornered wheat, sent bread prices up and made about $5 million, roughly $185 million today.
how it works
To corner a market, a trader buys up most of the available supply and the futures contracts that promise more. Anyone who has to deliver the commodity must then buy from the cornerer at whatever price is demanded. The trader profits until the stock is released or the scheme collapses.
so what
A century on, it still shows how markets can be rigged by someone who controls supply, and how the people at either end, farmers and eaters, pay for it. It also helped establish editing as a way to argue a point, not just tell a story.
the bigger pattern
Corners have recurred whenever supply could be locked up, from the Hunt brothers' attempt on silver in 1979 to 1980 to the 'Black Friday' gold panic of 1869. Many such schemes end by collapsing, and the response is often new rules on speculation.
fun fact
In the film the Wheat King dies by falling into a grain elevator and being buried in the wheat he hoarded, an ending borrowed from Norris's novel The Octopus.
more on this
background
A Corner in Wheat is a 1909 American short silent film which tells of a greedy tycoon who tries to corner the market in wheat, destroying the lives of the people who can no longer afford to buy bread. It was directed by D. W. Griffith and adapted by Griffith and Frank E. Woods from a novel and a short story by Frank Norris, titled The Pit and "A Deal in Wheat". Griffith may have had a real-life inspiration: six months earlier, James A. Patten had actually cornered the market in wheat, and in some cities, the price of bread doubled from five cents to ten, just as in the movie.
In 1994, A Corner in Wheat was selected for preservation in the United States National Film Registry by the Library of Congress as being "culturally, historically, or aesthetically significant".
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