Yini ebangela amagagasi olwandle?
Amagagasi amade ahamba olwandle abangelwa amandla adonsela phansi enyangeni emhlabeni. Lapho iphuzu eliphakeme kunawo wonke lamagagasi esikhathi eside lifinyelela ogwini, le ndawo iba namagagasi aphakeme. Lapho iphuzu eliphansi kunawo wonke lamagagasi, i - trough, lifinyelela ogwini, le ndawo iba namagagasi aphansi. Iningi lomhlaba linamanzi futhi amanzi "akhomba" enyangeni, izingxenye zomhlaba ezihlangabezana namagagasi aphakeme amanzi adonsela enyangeni. Amanzi "akhomba" abheke enyangeni akhiwa ngoba amandla adonsela phansi enyangeni aqine kakhulu kunoma yiluphi uhlangothi loMhlaba abheke kulo. Amandla adonsela phansi adonsela ulwandle enyangeni bese kuba negagasi.  Ukuqhuma okuphambene noMhlaba kubangelwa ukungabi namandla. Amanzi asuka enyangeni amelana namandla adonsela phansi azama ukuwadonsela kolunye uhlangothi. Ngenxa yokuthi amandla adonsela phansi enyanga abuthakathaka kakhulu ohlangothini olukude loMhlaba, amandla okuziphendukela kwemvelo ayaphumelela, ulwandle luyavuleka bese kuba negagasi. Njengoba uMhlaba uzungeza, izindawo ezihlukahlukene zeplanethi zibheke enyangeni, futhi lokhu kuzungeza kubangela ukuba amagagasi azungeze iplanethi.