In a food processor with the steel blade, puree the tongue and ham.
Set aside.
Make a white sauce by heating the butter and oil in a saucepan.
Add the flour and saute for a few minutes.
Gradually blend in the milk to form a smooth paste.
Season to taste with salt, pepper and nutmeg.
Set aside.
Pour the gelatin and water into the top of a double boiler and place over hot water, stirring until gelatin is dissolved.
Combine the gelatin with the white sauce.
When cool, add the mixture and the salad dressing to the tongue and ham.
Process until smooth.
Fold in the whipped cream and whipped egg whites, mixing well.
Pour into greased six-cup ring mold.
Chill overnight or up to two days in advance of serving.
When ready to serve, carefully unmold onto serving platter and garnish with a ring of parsley and decoratively cut radishes.