Thaw Ducklings. Remove giblets; wash giblets. Cover with boiling salted water and cook until tender, about 45 minutes. Drain. Pour rice slowly into boiling water; add salt. Cover. Simmer 5 minutes. Drain. Place in upper part of double boiler; add boiling chicken broth. Cover. Steam until rice tender and liquid absorbed. To melted butter add onion, parsley, marjoram and celery. Season with salt and pepper. Add steamed rice and chopped cooked giblets. Wash ducks. Pat dry. Brush ducks inside and out with 3 tablespoons orange juice.
Preheat oven to 325 deg. F. Stuff body cavities of birds with rice mixture. Truss. Place in shallow roaster. Mix remaining orange juice, orange rind and wine. Pour over birds. Reoast 3 to 3-1/2 hours, or until drum sticks move easily when grasped with fingers. Baste frequently with orange-wine mixture in pan.