Slice
unpeeled oranges very thinly; reserve seeds. Put seeds and 250ml of the
water in small bowl; cover, set aside. Place sliced fruit in large bowl
with remaining water. Stand both fruit mixture and seeds, separately,
overnight.
Drain seeds
over small bowl; reserve liquid, discard seeds. Combine fruit mixture
and seed liquid in large saucepan; bring to a boil. Reduce heat; simmer,
covered, about 1 hour or until rind is tender. Measure fruit mixture,
allow 220g sugar to each cup of fruit mixture. Return fruit mixture with
sugar to pan; stir over heat, without boiling, until sugar dissolves.
Boil, uncovered, stirring occasionally, about 30 minutes or until
marmalade jells when tested. Stand 5 minutes, stir in whisky. Pour hot
marmalade into hot sterilized jars; seal while hot.
