Wash and cut the lemons in quarters. Cut the pith off the rind and reserve it. Cut the rind into fine shreds with a sharp knife or in a food processor. Put the rind in a large bowl. Cut the fruit finely, reserving the seeds. Add the fruit to the bowl and cover with 11/2 qt. of the water. Soak the seeds and pith separately in the remaining water for six hours.

Tie the fresh ginger in a cheesecloth bag. Strain the water from the seeds and pith into a preserving kettle and add the bag of ginger. Put in the fruit and rind with its soaking water. Bring to a boil, cover and simmer for 30-40 minutes.

Remove the bag and strain the lemon mixture through a jelly bag for two hours. Add the sugar and crystallized ginger. Stir over a low heat until the sugar has dissolved. Bring to a boil and boil rapidly for about 10 minutes, stirring occasionally, or until setting point is reached.

Pack the marmalade into hot, clean jars, leaving 1/2-inch head room. Wipe the jars carefully with a clean cloth. Adjust the lids and process in a boiling water bath for 10 minutes. Complete the seals if necessary and let cool.