This Mortal Coil
Sunday
It was fitting that Dorothy lived in Kansas. With over 1,200 tornadoes annually, the US experiences about four times more twisters than all other nations combined, and the Great Plains states are America’s “Tornado Alley.” Two huge geographic features cause this: The Rocky Mountains and the Gulf of Mexico. The Gulf, Earth’s warmest water body at its latitude, supplies warm, moist air that flows north at low altitudes. When this meets cold, dry, high air blowing off the Rocky Mountains, the recipe is perfect for forming tornados.
Monday
“Death spiral” often refers to a causation loop which makes the situation continuously worse. For example, a small town loses population, so it receives less tax money to fund basic services, so it raises taxes to make up the loss, so more residents leave to avoid the higher taxes, etc. However, “death spiral” (AKA “graveyard spiral”) was originally an aviation term which began when early pilots experienced extreme sensory disorientation from flying through clouds, dense fog, or darkness with no view of the horizon for reference. Pilots often reacted to this with an instinctive slow turn, but disjointed visual and equilibrium cues led them to misjudge actual angle and elevation, causing pilots to bank further and descend more, initiating a “death spiral” which was often ended in a crash. On-board instruments were developed to give pilots a better sense of their true positions and orientation relative to the horizon when personal perceptions could not be relied on.
Tuesday
The often-raucous party game Twister began with a flash of inspiration from an ad executive hired to do something much different: create a promotional display for a shoe polish company (this same executive, Reyn Guyer, later invented the Nerf ball). He brought in some game developers, and after passing on the name “King’s Footsie,” and finding “Pretzel” unavailable, settled on “Twister” before selling Milton-Bradley the rights to it. Twister did not initially sell well, since company execs had reservations about the sexually suggestive nature of the game, and Sears refused to sell it in their catalog for the same reason. However, in May of 1966, Johnny Carson and the beautiful Eva Gabor played the game on The Tonight Show to great hilarity, and the game became an immediate success.
Wednesday
The invention of the screw thread goes back to about 4000 BC, but its use as a fastener came last. Early screw threads were used in food presses to produce oil and juice, particularly from olives and grapes. Later the water screw was employed as an efficient pre-motorized water removal device, and only in the late 1700s was a reliable screw-cutting lathe developed that let large-scale fastener screw manufacture possible.
Thursday
“The eye of the storm” in common language means to be in the center of a large, often public dispute. In terms of hurricanes, typhoons, and cyclones, however, the center, or “eye” is typically of a lower pressure and much more peaceful than the spiraling storm whose walls encircle it and spread out from there.
Friday
The Slinky was invented by accident when engineer Richard James, working on springs to steady sensitive Navy equipment at sea, knocked one off the shelf an observed its famous motion. He and his wife borrowed $500 to develop the toy, and by the end of the 20th Century, a quarter billion had been sold.
Saturday
A spiral is one of the three classifications of galaxy shape, along with elliptical and irregular. Our own galaxy, the Milky Way, is elliptical.