Wash, quarter, and remove stems of crab apples. Rinse berries. Place both in an enamel or stainless steel saucepan and add enough water to just show. Do not float the fruit. Cook until fruit is soft. Strain through a jelly bag, and discard everything but the juice. Simmer another 5 minutes, straining off any froth. Measure juice, add sugar in equal parts, and bring to about 210 degrees F, until the jelly drips from a spoon in sheets. Fill hot, sterilized jelly jars, and cover with 1/8 inch of paraffin.