24: The sails visible along the roofline of New Orleans Square were installed to cover giant searchlights.
In 1994, Disneyland began “The Lights Fantastic,” a network of gigantic searchlights positioned at various points around the Park, where the colored beams could synchronize in a nighttime display. Each searchlight was 7,000 watts and fully automated, with twenty-one total in the park: five atop Pirates of the Caribbean, five at Mission to Mars, five more behind Toontown, and three on each side of Fantasyland. An Herb Ryman conceptual painting of New Orleans Square, created to provide tone before more specific designs were drawn, includes just such a scene of sails peeking over the roofline, and this view inspired designers to capture Ryman's original concept when covering up the Lights Fantastic.
From: 101 Things You Never Knew About Disneyland by Kevin Yee and Jason Schultz
It appears that there was to be a show invovling (or maybe there was, I don't remember) massive search lights around the park. When they went to cover up the lights, the used the sketchs drawn by Herbert Ryman to design them. Good book by the way. Fun to read. Short though.