[From 1978 edition of How It Works volume 2.]|
The Archimedean screw has been used since ancient Egyptian times as a primitive method of lifting water. Essentially it consists of a screw thread surrounded by a close fitting water-tight cylinder. One end of this device is dipped into the water and the whole machine is rotated. Water in the thread at the bottom tends to be ‘wound’ up the axis of the machine until it spills out at the top, the action being like that of a continuous moving bucket.
JACK AND JILL AT THE MILLENNIUM 3000 AGRICULTURAL EXHIBITION ON MARS
Jack: The holo-text says it’s an Archimedes’ Screw.
Jill: Who or what is an Archimedes?
Jack: I think he was an ancient Earthling who lived in a place they used to call Greece.
[Syracuse, in Sicily, actually.]
Jill: Why did they name that thing after him?
Jack: Well, this is how Archimedes irrigated his garden on Earth.
Jill: With an H2O bottle and a green screw?
Jill: Okay, to do you a favor, I will suspend my disbelief.
Jack: What part don’t you believe?
Jill: The part that ancient Earthlings had H2O bottles, and they probably didn’t have screws either.
Jack: Of course they had screws. How else would they have opened wine bottles if they didn’t have corkscrews?
Jack: You’re right about one thing. Archimedes’ sprinkler system didn’t work properly, because there were no machines on ancient Earth to power it.
Jack: In the cave below the garden there was a crank handle that rotated the screw and a barrel containing the H2O. To lift the H2O in the bottle, the Earthlings had to turn the handle very fast, and a pressurized column would spout from the nozzle.
Jill: Then it did work.
Jack: It worked for Archimedes.
“By ox-eyed Lady Here and laughter-loving Aphrodite,” Archimedes puffed, wiping his brow, “I must return this leaky barrel to Diogenes in the 5th Century BC. He will be upset with me if I don’t.”
[Although an eminent mathematician, mechanist and engineering scientist in antiquity, the first time machine wasn’t invented until much earlier.]
There are those who would dispense with all their earthly goods and material possessions and spend the rest of their lives inside a barrel. Others who would say, it depends on
the barrel. Last but not lost, there are some (I know they exist) who would claim (unreasonably) there is no such thing as a barrel.
The Stopper: rem — By Windows Setup.
Invisible detail #2...
1. Too much light from point sources can be harmful.
2. Some objects get overexposed more than others.
3. The worst offenders are multifaceted, nearly white and not quite invisible, viz. spray.
Is the screw turning, let me see now, clockwise or counterclockwise?
I will accept the correct answer as proof that you are not a lazy person.
Wrong answers will also be evaluated.