Rub inside of body cavity of cleaned guinea hen with butter, pepper, and salt.
Place onion, carrot, and celery in the cavity.
Truss., guinea hen, and place breast side down on a rack in an uncovered roaster.
Place salt pork strips over the back, and bake 43 min in a moderate oven of 350°F.
Then turn bird over, and place the salt pork strips over the breast.
Bake for 43 min longer, or until tender.