The Pythagoras Cup
The Pythagoras cup is also called a Greedy cup. Its secret lies in its central column, which houses an upside-down-u-shaped pipe. Today, some toilets use the same ancient design as a flushing mechanism.
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from Periodic Videos
Key Facts In This Video
Pythagoras invented the Pythagoras cup so that none of his students would receive more than their share of wine. (0:19)
Watch an animated demonstration of how the Pythagoras cup prevents drinkers from getting too greedy: (1:48)
Putting liquid mercury at the bottom of a Pythagoras cup will prevent it from working. (3:09)