For crust, prepare and roll out pastry. Line a 9-inch pie plate. Trim pastry to 1/2 inch beyond edge of pie plate. Fold under edge; flute. Prick the bottom and sides of the crust with tines of a fork. Bake in a 450 degree oven for 10 to 12 minutes. Cool pie on a wire rack.
Combine the gelatin and the water. Let stand for 5 minutes.
In a medium saucepan, bring the milk and 3/4 cup sugar just to a boil. Remove the saucepan from the heat.
In a medium mixing bowl, beat the egg yolks with 1/2 cup of the hot milk mixture. Beat into remaining mixture in the saucepan.
Cook and stir over medium heat till mixture coats a metal spoon. Do not boil. Remove from heat.
Stir in the softened gelatin and rum. Transfer to a mixing bowl. Cool in the refrigerator till the mixture begins to set.
In a large mixing bowl, beat 1 cup of the whipping cream till soft peaks form (tips curl). Fold into gelatin mixture. Chill till the mixture mounds when spooned, stirring occasionally. Turn into cooled pie crust. Cover and chill for 6 to 24 hours or till filling mixture is set.
Before serving, beat the remaining whipping cream with the 1 tablespoon sugar till stiff peaks form (tips stand straight). Spread or dollop over pie. Sprinkle with some ground nutmeg. Makes 8 servings.
You can freeze this pie and take it from the freezer 1 hour before serving.