Wash and remove any green or spoiled grapes.
Weigh the sound grapes and place in a boiler.
Add 1 cup water to each 5 pounds grapes.
Simmer for 5 minutes, then strain through fine cloth or a jelly bag, pressing out all juice.
Measure the juice and add 1/2 cup sugar for each quart juice.
Bring to simmering temperature, stirring until the sugar is dissolved.
Pour into sterilized containers and adjust jar lids.
Process in 190-degree water in a waterbath canner for 30 minutes.