About 3 lbs. ripe concord grapes (this will yield 4 c. of juice)
7 c. sugar
1/2 bottle Certo fruit pectin
1 jelly bag or a sq. yard of cheesecloth several layers thick
Colander

First, prepare the fruit. Stem about 3 pounds fully ripened grapes and crush thoroughly in large saucepan. Add 1/2 cup water; bring to a boil and simmer, covered, 10 minutes. Place jelly bag or cheesecloth inside colander and place colander into large pan. Pour fruit and liquid in colander and close fruit bag or cheesecloth and make a large twist at top. Squeeze out juice. Use a potato masher to press jelly bag and help get all the juice from the grapes. Be sure you have 4 cups of juice when done squeezing in large saucepan.

To the measured juice, add 7 cups of sugar and mix well. Place over high heat and bring to a boil. Stir in 1/2 bottle of fruit pectin. Then bring to a full rolling boil and boil hard for 1 minute, stirring constantly. Remove from heat and skim off foam with metal spoon.

Pour quickly into glasses. Cover at once with 1/2 inch paraffin (melted to seal). Cover with metal lids or paper lids when completely cool. Label jars. Yields: About 10 med. glasses (5 lbs. jelly).