THE CUP OF JUSTICE

THE PYTHAGOREAN CUP:

THE CUP OF JUSTICE

The Pythagorean cup (also known as greedy cup, cup of justice, Pythagoras cup, Tantalus cup or i koupa tis dikaiosynis) is a practical joke device credited to Pythagoras of Samos. When it is filled up to a certain point a siphoning effect causes the cup to drain all its contents.

DESIGN AND WORKING :-

The phenomenon used is the simple bell siphon. The exterior of the cup is similar to the normal ones but in the interior it has a central vertical column like a Bundt pan. This column is placed directly above the stem or the grip of the cup. A hollow column runs through the stem into the central column to a certain height. This height determines till which level the cup can contain the contents. 

When the cup is filled the liquid rises to the second pipe up to the top of central column satisfying Pascals principle of communicating vessels. As the gravity creates a Siphon the liquid flows out of the bottom. Most modern toilets use the same principle. The following pictures are of the cross section of the cup and working: 

A Greek tale states that Pythagoras once testing his students presented them drinks in these cups, one of his students wanting more drink than the others filled it above the normal level, causing all of it to drain through the hole in the bottom and leaving the cup empty.

A Pythagorean cup sold in Crete, known as                       
                                 o kounenos tis dikaiosynis ("the cup of justice")

VERSIONS :-

There are quite a lot of versions to the Greedy cup after centuries of moderation. The following are some versions of the same : 

Make sure you check out other joke devices like dribble glass, fuddling cup, puzzle jug, Heron's fountain etc.

IF YOU LIKE OUR CONTENT 

 

SHARE - LIKE - COMMENT - FOLLOW - SUBSCRIBE

SOURCES: Wikipedia.

BY,                                

TAHA MOHIUDDIN