* The island of Pythagoras and the goddess Hera.

THE PYTHAGOREAN CUP ΟR THE CUP OF JUSTICE
It is considered that it was invented by Pythagoras, who wanted to teach his students about the necessity of having moderation in their lives. It is also called the ‘cup of justice,’ because it expresses the basic principles of justice, hubris, and nemesis. When moderation is exceeded (hubris) both what has been exceeded and what has been gained up to that point is lost.
How the cup works:
A hole is located in the cup’s central column, connected with the hole at the bottom of the cup through a pipe. The shape of the pipe can be represented as a straw that has been bent to an extreme point.
As the cup is filled with wine up to the limit (dotted line), the pipe inside the column gets filled at the same time. The level of the wine remains the same because of Pascal’s principle of communicating vessels. The pressure on the free surface of the wine is equal to the atmospheric pressure, which is the same to the pressure in the hole at the bottom of the cup. However, when the level of the liquid crosses the dotted line, the pipe fills with wine and the excessive liquid spills out of the bottom, until the whole cup is emptied.