Blueberry Shortcake

1 pint blueberries, washed and drained; 
1/3 cup water 
1 tablespoon butter or margarine 
2/3 cup sugar 
2 teaspoons cornstarch 
1/8 teaspoon allspice 
1/8 teaspoon salt

Put berries and water in saucepan. 
Cook easily until mix boils, stirring occasionally. 
Add butter. 
Mix dry ingredients together and add to the berry mixture. 
Boil gently for 7 minutes, stirring all the time. 
Serve hot or cold on hot buttered biscuits, with cream or whipped topping.