Oh

https://books.google.com/books?id=FtEPAAAAYAAJ&pg=PA89

In his 1886 book The Present Age and Inner Life, “Poughkeepsie Seer” Andrew Jackson Davis gives a surprisingly concrete explanation of table-turning at a seance:

We are negative to our guardian spirits; they are positive to us; and the whole mystery is illustrated by the workings of the common magnetic telegraph. The principles involved are identical. The spirits (improperly so called) sustaining a positive relation to us, are enabled through mediums, as electric conductors, to attract and move articles of furniture, vibrate the wires of a musical instrument, and, by discharging, through the potencies of their wills, currents of magnetism, they can and do produce rappings, on principles strictly analogous to the magnetic telegraph, and may move tables or tip them, to signify certain letters of the alphabet.

In her 1972 study of the spiritualist movement, Georgess McHargue writes that Davis’ scientific passages are so packed with “gobbledegook as to put it in the class with the most imaginative vintage science fantasy.”

| Oddities · Science & Math

Getting There

https://www.youtube.com/watch?v=IPI4JiO3-z0

Designed by architects in Amsterdam and Beijing, the Lucky Knot Bridge in Changsha, China, combines three bridges in one. Inspired by both the Möbius strip and the Chinese knotting art, the 185-meter pedestrian bridge spans Dragon King Harbor River, connecting multiple levels at varying heights (the river banks, the road, and a park at a higher level) while permitting pedestrians to pass from one route to another using “moon gates.”

“Bridges … have a highly metaphorical quality,” Michel Schreinemachers, a partner at Next Architects, told Wired. “They connect not only in a physical sense, but also people, places, needs, and experiences.”

| Art · Science & Math · Technology

Decision Time

When you’re driving and see an upcoming traffic light turn yellow, you face an urgent choice: stop quickly or try to run through the intersection before the light turns red. In 1962, Stanford aeronautics professor Howard Seifert worked out that you can choose either alternative if

\displaystyle \left ( v_{0}T + \frac{1}{2}a^{+}T^{2} - s \right ) > d_{0} > \frac{1}{2}\left (v_{0}^{2} / a^{-} \right ),

where your car’s initial speed is v0 ft/sec, its maximum acceleration is a+ ft/sec2, its maximum deceleration is a– ft/sec2, the duration of the yellow light is T seconds, and the intersection is s feet wide and d0 feet away.

“[I]f the left or right inequality is reversed, you will not be able to run through or to stop, respectively,” he concluded. “It can be shown that there are situations where neither alternative will work and hazard and law violation are inevitable, as some palpitating drivers will testify.”

(Howard S. Seifert, “The Stop-Light Dilemma,” American Journal of Physics 30:3 [1962], 216-218.)

| Science & Math

Disappearing Act

https://commons.wikimedia.org/wiki/File:Quantum_Man.jpg
Image: Wikimedia Commons

Julian Voss-Andreae studied physics at the University of Vienna before pursuing an art degree in the United States. His sculpture Quantum Man consists of 115 vertical steel sheets spaced by 1,000 short steel rods. The resulting figure looks solid when viewed from the front but almost disappears when viewed from the side, as light passes between the sheets.

“My interest is really nature,” he says. “One way to explore it is through science. Another is through intuitive sense and a search for metaphors.”

(Thanks, Ron.)

| Art · Science & Math

Handiwork

In their early studies of time and motion, engineers Frank Bunker Gilbreth and Lillian Moller Gilbreth divided all motions of the hand into 17 varieties:

https://commons.wikimedia.org/wiki/File:Therblig_(English).svg
Image: Wikimedia Commons

Magnificently, they called these therbligs, which is roughly Gilbreth spelled backward. “Transport empty” refers to receiving an item with an empty hand, “transport loaded” means moving an object with the hand, and so on. With careful study, a worker’s movements might be optimized to maximize speed and efficiency. (It was the Gilbreths, for example, who suggested that surgeons employ “caddies” to pass their instruments to them.)

This scheme makes an appearance in fiction: In their 1948 novel Cheaper by the Dozen, Frank and Lillian’s children Frank Jr. and Ernestine describe what it’s like to grow up in the home of an efficiency expert:

Suppose a man goes into a bathroom and shave. We’ll assume that his face is all lathered and that he is ready to pick up his razor. He knows where the razor is, but first he must locate it with his eye. That is ‘search’, the first Therblig. His eye finds it and comes to rest — that’s ‘find’, the second Therblig. Third comes ‘select’, the process of sliding the razor prior to the fourth Therblig, ‘grasp’. Fifth is ‘transport loaded’, bringing the razor up to his face, and sixth is ‘position’, getting the razor set on his face.

“There are eleven other Therbligs — the last one is ‘think’!”

| Science & Math

In a Word

amphiscians
n. inhabitants of the tropics

angustation
n. the condition of being narrowed, constricted, limited, or confined

caducity
n. frailty, transitoriness

avolation
n. the act of flying away

This is the song of the last male Kauaʻi ʻōʻō, recorded in the Alaka’i Wilderness Preserve on Kauaʻi in 1987. Rats, pigs, hurricanes, and disease-carrying mosquitoes had reduced the species to a single pair by 1981, and the female was not found after Hurricane Iwa in 1982. The male was last seen in 1985. This appears to be his song, overheard two years later, the last trace of a vanishing species.

| Death · Language · Science & Math

Tribute

Every species of spider in the genus Predatoroonops takes its name from an element in John McTiernan’s 1987 film Predator:

Predatoroonops anna: For the character Anna Gonsalves, played by Elpidia Carrillo
Predatoroonops billy: For the character Billy Sole, played by Sonny Landham
Predatoroonops blain: For the character Blain Cooper, played by Jesse Ventura
Predatoroonops dillon: For the character George Dillon, played by Carl Weathers
Predatoroonops dutch: For the character “Dutch” Schaeffer, played by Arnold Schwarzenegger
Predatoroonops maceliot: For the character “Mac” Elliot, played by Bill Duke
Predatoroonops poncho: For the character “Poncho” Ramirez, played by Richard Chaves
Predatoroonops rickhawkins: For the character Richard Hawkins, played by Shane Black
Predatoroonops schwarzeneggeri: For Schwarzenegger
Predatoroonops vallarta: For Puerto Vallarta, Mexico, a filming location
Predatoroonops valverde: For Val Verde, the fictional country where the film takes place
Predatoroonops chicano: An alternate nickname for Poncho
Predatoroonops mctiernani: For McTiernan
Predatoroonops olddemon: In Anna’s village the Predator is known as a “demon who makes trophies of men”
Predatoroonops peterhalli: For Kevin Peter Hall, the actor who played the creature
Predatoroonops phillips: For the character Homer Phillips, played by R.G. Armstrong
Predatoroonops yautja: The name of the Predator species in the expanded universe

Also: In Predator 2, the Predator’s trophy case contains the head of an alien from the Alien franchise:

https://www.youtube.com/watch?v=E8wU2XMpM8E

| Entertainment · Science & Math

Sesquipedalian

In the August 1841 issue of Graham’s Magazine, Edgar Allan Poe published a cryptogram composed by a Doctor Frailey of Washington and offered a year’s subscription to any reader who could solve it. In October he published the solution, which he’d managed to find:

In one of those peripatetic circumrotations I obviated a rustic whom I subjected to catechetical interrogation respecting the nosocomical characteristics of the edifice to which I was approximate. With a volubility uncongealed by the frigorific powers of villatic bashfulness, he ejaculated a voluminous replication from the universal tenor of whose contents I deduce the subsequent amalgamation of heterogeneous facts. Without dubiety incipient pretension is apt to terminate in final vulgarity, as parturient mountains have been fabulated to produce muscupular abortions. The institution the subject of my remarks, has not been without cause the theme of the ephemeral columns of quotidian journalism, and enthusiastic encomiations in conversational intercourse.

He was upbraided in November by a Richard Bolton of Pontotoc, Mississippi, who’d sent in a solution but received no credit. Poe redressed the error and added, “Your solution astonished me. You will accuse me of vanity in so saying — but truth is truth. I make no question that it even astonished yourself — and well it might – for from at least 100,000 readers — a great number of whom, to my certain knowledge, busied themselves in the investigation — you and I are the only ones who have succeeded.”

| Language · Science & Math

Spaceship Away

https://commons.wikimedia.org/wiki/File:Arthur_C._Clarke_1965.jpg
Image: Wikimedia Commons

The standards for the British science fiction comic Dan Dare, Pilot of the Future were so high that the editors hired a young Arthur C. Clarke to serve as science and plot adviser. Clarke wrote to publisher Marcus Morris in spring 1950:

I think this might amuse you. Yesterday I was lecturing at the Royal Geographical Society on the problem of interplanetary navigation … After a highly technical series of remarks, [one of the other speakers] ended up by asking ‘Will Dan Dare reach Venus?’

He did. Clarke left the job after six months — he was said to have thought that “the standard of work and research was so high that they were wasting their money getting him to check it.”

(From Jason Dittmer, Comic Book Geographies, 2014.)

| Literature · Science & Math