Take ten or twelve knuckles, such as are cut off from legs and shoulders of mutton, at the very shank; rub them with a little salt, put them in a pan of water for two or three hours, and wash them very clean; boil them in a gallon of spring water for an hour. Strain them very clean, then put in two ounces of hartshorn shavings, and the bottom crust of a penny loaf; let it boil till the water is reduced to about three pints; strain it off, and when cold skim off the fat. Take half a pint warm before you rise, and the same in bed at night. Make it fresh three times a week in summer, and twice a week in winter: do not put in any lamb bones. This is an excellent thing.