Preheat an oven to 425°F. Position a rack in the bottom third of the oven. Oil a V-shaped rack in a roasting pan.

Remove the neck, gizzard and heart from the turkey, if included; reserve for another use. Rinse the bird in cold water and pat dry with paper towels. Place the onion, celery, parsley and bay leaf in the cavity. In a small bowl mix together the sage, thyme and marjoram. Place 2 teaspoons of the mixture in the cavity, then sprinkle with salt and pepper. Truss the turkey, if desired; brush with some of the butter and sprinkle, especially the breast and thighs, with the remaining herb mixture and salt and pepper.

Place on the rack in the pan, breast-side down. Roast for 40 minutes, basting with butter after 20 minutes. Reduce the heat to 325°F, turn breast-side up and continue to roast, basting with the remaining butter until used up and then with the pan juices every 15 - 20 minutes. Roast until golden and cooked through. After about 2-1/2 hours, start testing for doneness by inserting an instant-read thermometer in the thickest part of the breast away from the bone; it should register 165°F. Alternatively, insert it in the thickest part of the thigh; it should register 180°F. The turkey should roast a total of about 3-1/2 hours or 15 - 17 minutes per lb.

Transfer to a warmed platter and cover loosely with aluminum foil until ready to carve, about 20 minutes. Meanwhile, use the pan juices to make the Chicken o Turkey Gravy. Carve the turkey and serve with gravy.