1. Soak gelatin in lemon juice for about 5 minutes.
2. Chill a 2-quart soufflé dish or dessert bowl.
3. In the top of a double boiler, combine the milk, egg yolks, sugar, and salt (if desired); with a rotary beater, blend them until mixed thoroughly. Over boiling water, cook the mixture, stirring constantly, until it thickens and coats a metal spoon. Remove the utensil from the heat.
4. Add the gelatin, ginger marmalade, and vanilla, stirring to blend the mixture well. Transfer it to a mixing bowl and chill it until it just begins to set (perhaps an hour--watch closely. If you wait too long, it will coagulate into lumps and be ruined).
5. With a rotary beater, briefly whip the mixture to assure its smoothness. Fold in the whipped cream. Beat in one-fifth of the egg white; fold in the remainder. Using a rubber spatula, transfer the mixture to a prepared dish and chill it for at least 6 hours, or until it is thoroughly set.
Note: this does have raw egg whites in it, so be careful about serving it while still chilled. You don't want to leave it out on a hot summer's day or you could run the risk of food-borne illness.