Blackberry and Sloe Jelly

• 4lb blackberries
• 1lb sloes
• Sugar

Put the blackberries into a pan with the sloes which have been pricked with a needle. Cover with water and simmer until tender. Strain through a jelly bag and measure the juice. Allow 1 lb sugar to each pint of juice. Heat the juice gently, stirring in the sugar until dissolved. Boil hard to setting point and pour into hot jars. Cover.