Pour maple syrup into 2-quart saucepan. Boil to 238 degrees on candy thermometer (soft-ball stage). Pour on buttered marble slab or platter. Cool to lukewarm. Work until creamy. Mixture may be cooled in pan in which it has been cooked and beaten with wooden spoon until mixture loses its gloss. Pour or pat in wax-paper-lined pan. Cut for fudge.