A good cup sponge cake
Beat the yolks and whites of five eggs separate. Into the yolks stir a cupful of sugar and a small teacupful of flour that has been well sifted with a small teaspoonful of baking-powder. Beat long and hard—if you do it for twenty minutes it will not be too long. Add a teaspoonful, each, of lemon and orange juice and fold in lightly the stiff whites. Bake at once in a loaf tin in a steady oven. It should be done in three-quarters of an hour.