Place the washed and stoned cherries in a preserving-pan with the water and lemon juice. Cook gently with the lid on for 15 min. Remove lid. Add the sugar and stir over gentle heat until it has dissolved. Bring to a full rolling boil and boil rapidly for 3 min. Remove from heat, stir in the pectin, return to heat, bring to boil and boil 1 min. only. Cool for 15 min. to prevent fruit rising. Pot and put on waxed discs immediately. Cover and label.