Source: Vintage Recipes from Old Time Pickling and Spicing Recipes - Florence Brobeck (c. 1953)
1 cp (packed) brown sugar
1 cp cider vinegar
1 cp water
1/2 tsp allspice
1/2 tsp whole cloves
1 (four-inch) stick cinnamon, broken
1/2 tsp mustard seds
1/4 tsp celery seeds
1 cp chopped peeled onions
1 1/2 cps sliced fresh or thawed quick-frozen rhubarb
1 cp seedless raisins
1 - combine sugar, vinegar, water, and spices and seeds in an agate or enamel kettle, and boil about 2 minutes.
2 - Add onions and rhubarb; cover and cook slowly 30 minutes or longer.
3 - Rinse and drain raisins; add to hot mixture, cook 10 minutes uncovered.
4 - Stir a few times with wooden or enamel spoon.
5 - Serve when cold.
6 - Or seal while hot in hot sterile glasses.
Makes about 2 pints.