Source: Vintage Recipes from Old Time Pickling and Spicing Recipes - Florence Brobeck (c. 1953)
1 qt cider vinegar
1 cp sugar
2 cps washed fresh mint or spearmint leaves
1 - Heat vinegar and sugar together in agate or enamel kettle; crush leaves and add.
2 - Stir with enamel spoon, crushing mint against bottom of kettle.
3 - Boil about 5 minutes.
4 - Strain and pour into sterile bottles.
5 - Cork well.
Makes about 1 quart.