Peel orange and lemon. Finely chop rind and place in large cooking pan. Chop
orange and lemon pulp and set aside.
Add 3/4 cup water and baking soda to rind and bring to boil. Reduce heat and
simmer 10 minutes, stirring occasionally.
Add chopped orange and lemon pulp, blueberries and sugar. Return to boil. Reduce
heat and simmer 5 minutes.
Remove from heat and cool 5 minutes. Add pectin; return to a boil. Boil, stirring
constantly for 1 minute. Remove from heat and skim off foam with a metal spoon.
Pour into hot sterilized jars, filling to 1/4 inch from the top. Wipe jar rims.
Cover at once with metal lids and screw on bands.