Which word names both a water spirit of German folklore and to put a stop to something?

A wartime adviser to de Gaulle, who was president of France from 1969 to 1974? Which watch brand was introduced in the 1950s with TV "torture test" ads? Complete the proverb: "A watched pot never..." what? What is the water-filled barrier around a castle called? A water tower in Stanton, Iowa, a town of Swedish heritage, is painted to look like a giant what? The waterfall with the longest uninterrupted drop in the world, 3,212 feet, is on which continent? Which word names both a large waterfall and a clouding of the eye's lens? What is a watery mix of kitchen scraps fed to hogs called?