Beat the whites till stiff, then add gradually the sugar, butter, lemon extract, and milk, and last the flour. Butter a long shallow tin pan (13 inches long, 9 inches wide, and 1 inch deep), dust it with flour, pour in the mixture, smooth it even with a knife, and bake in a medium-hot oven.
Stir butter, sugar, and yolks to a cream, add lemon extract, flour, and milk; bake the same as the first part. When the cakes are nearly cold lay them over one another with a layer of jelly between, then cut it into fancy shapes like half moons, small rounds, and squares; glaze them with sugar glaze. In place of jelly, cream or any other filling may be taken. The two cakes may be spread separately with jelly, then rolled up like jelly rolls.