Make 6 slits almost to bone in pork loin. Place a slice of onion and applie in each slit. Rub roast with sage; tie securely. Roast fat side up at 325 degrees for 2 hours; pour off fat. Combine soup and wine, pour over meat. Roast 30 minutes more or until done, baste often with soup (total roasing time 35-40 minutes per pound). Remove meat from pan. On top of range, in roasting pan, add water to soup. Heat stirring to loosen browned bits; serve with roast.