Blackberry Acid - cooking recipe

Ingredients

12 lb. blackberries
1 qt. boiling water
5 oz. tartacid berries
sugar

Preparation

Thoroughly crush berries.
Pour boiling water over them.
Let stand overnight 12 hours.
Strain through a flour sack and let drain thoroughly.
Do not squeeze.
To each measure of this liquid, add the same amount of sugar to the mixture.
Add the bottle of acid to the mixture.
Put mixture in a container and seal.