Beat together 1 cup butter, 1 cup vegetable oil and 2 cups sugar. Beat in 2 eggs, 2 teaspoons and 1/4 teaspoon salt. Add 5 cups flour, 2 teaspoon baking soda and 2 teaspoon cream of tartar. Roll into walnut size balls. Place on cookie sheet and flatten with glass dipped in white sugar. May use red or green sugar for Christmas. Bake at 375 degrees oven for 10 minutes.