Hapi (Hep, Hap, Hapy) was probably a predynastic name for the Nile - later on, the Egyptians just called the Nile iterw, meaning 'the river' - and so it became the name of the god of the Nile. ('Nile' comes from the Greek corruption - Neilos - of the Egyptian nwy which means 'water'.) He was mentioned in the Pyramid Texts ("who comest forth from Hep") where he was to send the river into the underworld from certain caverns, where he was thought to have lived at the First Cataract. The Nile was thought to have flowed from the primeval waters of Nun, through the land of the dead, the heavens and finally flowing into Egypt where it rose out of the ground between two mountains which lay between the Islands of Abu (Elephantine) and the Island of Iat-Rek (Philae). Hapi was also mentioned in the Pyramid Texts as a destructive power, but one that worked for the pharaoh.