CHAPTER VI.--Second administration of Don Luis Velasco--His

great work for the Drainage of the Valley--Lakes in the Valley--Danger of Inundation--History of the Desague of Huehuetoca--Operations of the engineers Martinez and Boot--The Franciscans--Completion of the Desague--La Obra del Consulado-- Negro revolt--Extension of Oriental trade--Guerra Viceroy--De Cordova Viceroy--Indian revolt--Cordova founded, 178