Put two ounces of butter into an omelet-pan over the fire: as soon as it begins to fritter, break the eggs into it without disturbing the yolks; season with pepper and salt; fry the eggs over the fire for five minutes, and then remove them gently on their dish. Next, put two ounces more butter into the pan; fry it of a brown colour, then add two tablespoonfuls of French vinegar; boil the whole together for two minutes; pour it over the eggs, and serve.