This original postcard is from the 1933 Century Of Progress (Chicago World's Fair) which was held in Chicago. It is in good condition but has some slight wear and stains and the front features the "The Marvelous Scintillator Beams, Two Billion Candle Power". The reverse side features a postcard format, which is unused and a paragraph that says "The Most outstanding effect in night illumination is produced by the scintillator, consisting of a battery of twenty four arc searchlights having a total light output of 1,920,000,000 candlepower. Mounted on swivel & trunnion bases, these 36-inch projectors may be turned at any angle, to shoot variegated patterns of colored light into the sky. The scintillator is located on the shore of Lake Michigan just south of the Travel & Transport Building" and measures approx. 5 1/2" x 3 1/2".