Arrange a rack in the center of the oven and preheat to 450 degrees F. In a saucepan, combine the peaches, blueberries, water, sugar, cornstarch, and lemon juice and bring to a boil. Lower the heat and let simmer for 5 minutes.
Transfer the fruit mixture to a buttered, shallow 1 1/2-quart baking dish. Arrange the biscuits on top of the fruit mixture, and brush them with the cream and sprinkle with the sugar. Bake the cobbler until the biscuits are browned and the fruit is bubbling, about 15 minutes. Let the cobbler cool slightly and serve with the ice cream.
Recipe adapted from Gourmet Magazine