The level with water is an instrument ancestral and rudimentary, it rests on the principle of the communicating vases.

It is composed of a flexible tube (similar to a sprinkler pipe), at each end of which two special “bottles are fixed”. Those are generally graduated and called “feeding-bottles”. The bases of these last elements are connected to the pipe, the upper part being open to allow the balance of water. The stability of the liquid will determine two points of the same horizontal plane.

See too

• other types of levels