Preparation

Using a paring knife, score the peels of the oranges and lemon into 4 sections lengthwise. Remove the peels; scrape off the white pith. Cut peels into very thin strips. In a saucepan combine peels, water  and baking soda; bring to boiling. Reduce heat; cover and simmer 20 minutes. Do not drain.

 Meanwhile, section the peeled oranges and lemon over a bowl to catch the juice (discard seeds). Add fruit sections and reserved juice to saucepan; return to boiling. Reduce heat; cover and simmer 10 minutes or until thick.  In an 8- to 10-quart Dutch oven combine 3 cups of the fruit mixture plus sugar. Bring to a full rolling boil. Quickly stir in pectin; return to boiling; cook and stir, uncovered, 1 minute. Remove from heat; skim off foam. Immediately ladle mixture evenly  into hot, sterilized half-pint jars,  leaving a 1/4-inch head-space. Adjust  lids. Process in a boiling-water canner  15 minutes. Remove and let cool overnight. (Marmalade may take  up to 2 weeks to set.)