Mix and sift dry ingredients; add milk gradually, yolks of eggs well beaten, butter, and whites of eggs beaten stiff; cook on a greased hot waffle iron. Serve with maple syrup. A waffle iron should fit closely on range, be well heated on one side, turned, heated on other side, and thoroughly greased before iron is filled. In filling, put a tablespoonful of mixture in each compartment near centre of iron, cover, and mixture will spread to just fill iron. If sufficiently heated, it should be turned almost as soon as filled and covered. In using a new iron, special care must be taken in greasing, or waffles will stick.