Combine the first 4 ingredents in a saucepan. Stir hard, cooking over medium heat until mixture boils. Lower heat,cook & stir about 30 minutes. Mixture will thicken. Cooking is done when a small amount (about 1/4 to 1/2 teaspoonful) becomes brittle when dropped in a cup of cool water. Remove from stove. Add butter & stir. Pour into a buttered, shallow pan. Cool long enough so that candy can be handled. With buttered hands, stretch and pull candy until it is a light brown color. Cut in pieces & wrap in wax paper.