Soak all night, changing the water several times and having the last bath quite hot. Boil tender in hot water with a table-spoonful of vinegar. Take out the bones while hot, and let it cool before picking or shredding it into fine flakes. Heat a cupful of milk, stir into it a tablespoonful of butter rolled in one of flour, cook until it thickens well, take from the fire and add two beaten eggs. When these are well mixed, add the shredded fish, and cook two minutes, stirring steadily. A tablespoonful of minced parsley is an improvement, also, a little lemon-juice. Season with cayenne or paprica. Serve hot.