Preparation / Directions:
Boil 1 1/4 cups of the sugar in 1 3/4 cups of the water with a small amount of grated orange and lemon rind. Remove the syrup from the fire, add the strained juice from the oranges and the lemons, and transfer the mixture to an ice cream machine to chill it.
Set the remaining sugar and water to boil with the vanilla, and cook it down till a drop dropped on a plate remains round, and strings out when pressed between the fingers. While the syrup is boiling down, whip the whites till they're stiff; when the syrup is ready, whip it into the whites to make a frosting. once it has cooled, mix it into the sherbet. Stir in the rum and serve in ice cream cup