Pour the peaches into an 8 x8” baking dish. Stir together the sugar and butter. Combine the flour, salt, baking powder and stir in the butter mixture, alternately with the milk. Spread the batter over the peaches, Stir together the remaining sugar, cornstarch and salt and sprinkle over. Pour over the water. Bake in a preheated 325 °F. oven for 35 minutes or until browned.