Combine syrup, hot water and butter and bring to a boil. Mix cornstarch, salt and enough cold water to make a thin paste, add egg yolks and beat well. Add hot syrup mixture gradually, return to heat and cook untill thickened, stirring constantly. Cool slightly. Pour into cooked pie shell. Beat egg whites stiff, adding slowly the tablespoon of syrup. Pile on pie and brown in hot oven. Add chopped nut meats if desired to top.