In a kettle, combine the fish trimmings and bones, wine, lemon juice, onions, and herbs. Bring mixture to a boil, stirring frequently to prevent scorching, and boil it until liquid is reduced by half. Add 8 cups water and salt and pepper to taste. Bring to a boil, and skim it. Simmer for 20 minutes, strain it into a large saucepan, and let it cool. Skim again. Sprinkle gelatin over the stock and add the egg whites, beaten to stiff peaks, and the shells, crushed. (Do not stir in.) Bring stock slowly to a boil over moderate heat, whisking constantly. Remove pan from heat and let stand for 30 minutes. Strain the aspic through a fine sieve lined with a dampened kitchen towel. Let it cool. To apply to a dish, cool only until just thickened and paint or spoon onto the fish or other dish. To solidify, chill in refrigerator. Makes about 8 cups. Gourmet Mag.