Ibn al Haytham (died 1039 A.D. / 431 A.H.) was invited by the cruel and eccentric caliph al-Hakim to come to Egypt after speaking of the benefits of the Nile River. He proposed building a dam at Aswan to improve irrigation.
Ibn al Haytham (alikufa mwaka 1039 BK / 431 BH) alikaribishwa na mtu katili na maarufu Khalifa al-Hakim kwenda Misri baada ya kuongelea juu ya faida za mto Nile. Alipendekeza kujengwa kwa Bwawa la Aswan ili kuboresha umwagiliaji.