Blackberry Ketchup

4 lb (2 kg) ripe blackberries (about 3 1/2 quarts [3 1/2 liters])
2 lb (1 kg) brown sugar
2 cups (1/2 liter) vinegar
2 teaspoons (10 ml) ground cloves
2 teaspoons (10 ml) ground cinnamon
1 teaspoon (5 ml) ground allspice

Cook the blackberries slowly for two hours with the sugar, vinegar, cloves,
cinnamon, and allspice. When all is soft, put into jars and cover. Process.
Makes about 5 pints (2 1/2 liters).