The Greatest Dam. The world's greatest dam, the Senar, is 'being rushed to completion on the Blue Nile river, 2,000 miles south of Khartum, Africa, where Lord Kitchener Kitchen-er became famous. This dam will bring under Irrigated cultivation 3.000,000 acres of funning land now Idle. It will run a swarm of factories, mightier than the pyramids. Ancient way of conquering a territory terri-tory was to enslave the Inhabitants. Modern man's great conquests harness nature's forces and free human labor.