|Fresh lemon juice||1⁄4 Cup (4 tbs)|
Wash the fruit.
Slice into thin cartwheel slices.
Cut grapefruit cartwheels into thirds, orange and lemon into halves.
Measure the fruit into a large kettle and add 1 cup water for each cup fruit.
Bring to boiling; boil 20 minutes.
Remove from heat and measure the hot mixture; return to kettle and bring to boiling.
Remove from heat- and add 3/4 cup sugar for each cup of fruit and juice.
Stir with a wooden spoon until thoroughly blended.
Return to heat and return to boiling.
Boil 20 to 25 minutes, or until jellying stage is reached.
(To test, remove marmalade from heat and spoon a small amount onto a cold saucer; chill quickly.
If marmalade does not "set" to the proper consistency, cook a few minutes longer.) Just before removing from heat, stir in lemon juice.
Ladle into hot sterilized glasses and cover marmalade with melted paraffin