3 to 4 1/2 pint canning jars with lids and bands, sterilized and kept war (I use the dry cycle of my dishwasher), or about 6 4 ounce jelly jars, and have one extra just in case.
1 stockpot of boiling water for canning.
1 large saucepan for the marmalade.
1 large mesh tea ball or 3 smaller mesh tea spoons.
Scrub lemons well, then cut of a slice from each end and halve the lemons lengthwise. Scoop out all the seeds and the inner white pithy center and put them into the tea ball. Slice the lemons very thinly across, to make 2 cups.
Have a large stock pot about 3/4 full of water, and bring to a simmer. I use some of the bands held together with the twisty ties from the produce department to form a stand fitting the bottom of the pot, so the jars do not sit directly on the bottom of the pot.
Put lemons, ginger, 3 cups of water and the tea ball into a saucepan and cook until the peel is soft and it looks somewhat creamy, about 20 minutes. Take out a piece of peel and eat it, and if it is not completely soft, keep cooking it. When it is soft, add 3 cups of sugar and stirring, bring up to a rolling boil. Meanwhile, put a little plate in the freezer for testing. After it has come to a full boil, after about 15 minutes, dribble about 1/4 teaspoons on a cold plate, and if it stays firm enough to wrinkle on the top when you push the edge with your finger, it is ready to pour into the jars. Work very quickly now, pouring the boiling hot marmalade into the hot jars, wiping the rims with a cloth dipped into the boiling water and putting the lids and bands on. Process in the boiling water bath for 10 minutes, remove and wait to hear the 'pop' that indicates a vacuum has formed.