Cut a large dressed hare, or jack-rabbits, into serving pieces and let the pieces stand for 24 to 48 hours in a cool place, well covered with a marinade of 2 cups vinegar, 1 cup each of water and claret, 2 large onions, sliced, 1/2 tablespoon salt, 1 teaspoon each of mustard seeds, crushed juniper berries, and freshly ground black pepper, 8 whole cloves, and 3 bay leaves. Turn the meat every 12 hours.
When ready to cook, dry the pieces of hare, dust them lightly with flour, and sauté in 1/3 cup hot butter or good fat until well browned on all sides. Drain the excess fat from the pan. Strain the marinade, dilute it with 1/2 cup hot water, and pour it over the meat to cover. Bring the liquid to a boil, cover the pan tightly, and simmer the hare for about 40 minutes, or until the meat is tender. Add salt and pepper to taste and a little sugar if desired.
Arrange the meat on a heated platter and pour over it the gravy, strained and thickened with a little flour if necessary. Serve with potato dumplings.