Wash the duck and dry with paper towels. Combine the next 5 ingredients with 1 teaspoon of the salt. Pour the mixture over the duck. Marinate for 8 hours in the refrigerator.
Preheat the oven to 325 degrees. Wash the giblets and chop coarsely. Add the next 3 ingredients and the remaining salt. Chop the chestnuts and add. Mix well and spoon into the body and neck cavities of the duck.
Close the openings with skewers and lace tightly with string. Place the duck on a rack in a shallow baking pan large enough to hold the duck. Bake for at least 2 hours; cook for two and one-half hours for a crisp skin. Remove from the oven and let stand for about 10 minutes. Carve and serve.
Makes 4 servings