Squeeze juice
from mandarins, pour into large saucepan. Discard skins; chop mandarin
flesh coarsely. Add mandarin flesh, lemon juice and the water to same
pan; bring to a boil. Reduce heat; simmer, covered, 1 hour. Strain
mixture through large piece of damp muslin into large bowl; allow
mixture to drip through cloth for several hours or overnight. Do not
squeeze or press the mixture through the cloth as this will result in
cloudy jelly.
Measure the
strained liquid, discard pulp. Allow correct amount of sugar to each cup
of liquid. Return liquid with sugar to clean large saucepan; stir over
heat, without boiling, until sugar dissolves. Boil, uncovered, without
stirring, about 30 minutes or until jelly sets when tested. Pour hot
jelly into hot sterilized jars; seal while hot.