Water is considered for a long time an element of vital importance both for the subsistence of the man, and for the development of the civilization.
The birth and the development of a lot of populations has tightly been tied the man to the presence of courses of water and in the time has recognized in the water the ability to defend it from the illnesses and to facilitate him the recovery, for these motives since the antiquity has attributed to it magic virtue, to the point that gift of the was considered gods.