Select two pounds of the scrag end of young mutton. Cut the meat into small pieces, discarding all superfluous fat. Place in a casserole, after browning over in a little hot dripping, and add one cupful of dried flageolets (which are green-colored French beans), one pint of boiling water, two onions cut in slices, salt, celery salt and pepper to taste, and one small head of lettuce, torn in fine shreds. Cover the casserole and simmer for about three hours. A little more water may be required, but there should only be a small quantity of broth or gravy when it is properly cooked. Uncover for the last twenty minutes of cooking and serve in the casserole.