What is the principle of oil lamp?

The structure of the oil lamp is an oil pot underneath, a lamp holder above, and a wick post on the lamp holder, and a gear on the wick post can be rotated by a handle.
Connected to the upper and lower is the "wick". He is flat or round woven from cotton fabric. By turning the gear through the handle, the wick can move up and down in the wick column to adjust the size of the light.Kerosene Furnace Wick
Kerosene is poured into the bottom oil pot. The reason why kerosene can reach the upper wick head is supplied through the small gap of the wick braid. This phenomenon is called "capillary phenomenon". It is not a "siphon" phenomenon.