Peel the marrow, cut up three pounds of it into squares, sprinkle with salt, let stand for twenty-four hours, then drain. Mix together the cornstarch, mustard, turmeric, and one cupful of the vinegar. Put the remainder of the vinegar into a saucepan, add the onion, ginger, chilies, cloves and sugar and boil for ten minutes. Now add the mustard paste, bring to boiling point, add the marrow, and boil for thirty minutes.
Bottle and seal.