Siphon cup

Siphon cup
Is it only a cup?
No!
It is a magical cup!
Siphon Cup, also known as nine dragon fair cup, produced in China's Song Dynasty.
The magic of the cup is that it does not leak if the water(or vine) in the cup is not full, and it will leak out when the water in the cup is full.
The secret is that there is a siphon tube in the cup, which siphons form as the water diffuses across the siphon and the water in the cup leaks.
This cup I designed , siphon tube cleverly hidden in the cup