Peel, pit and chop the peaches. In a 8 quart stainless steel or enameled stockpot, cook the peaches, uncovered, over moderate heat for 8 minutes or until they are soft, stirring and mashing constantly. While the peaches cook, tie up the cinnamon stick and cloves in a piece of cheesecloth. Stir in the sugar and lemon juice, add the spice bag, and bring to a full rolling boil. Continue to boil, uncovered, stirring and skimming the surface often, for 25 to 30 minutes or until a candy thermometer registers 218ºF. to 220ºF. and the preserves have thickened slightly and appear golden and glossy. While the preserves cook, sterilize 8 half pint jelly jars. Spoon in the preserves, leaving a 1/2 inch head space in each, wipe the rims well and seal. Process in boiling water bath for 10 minutes, then let cool thoroughly and check the seals. Store in a cool, dark, dry place for up to 6 months. Makes 8 half pints.