Slice apples about 1 cm thick. Place in a well buttered baking dish. Pour melted butter over apples. Sprinkle with raisins, lemon juice and half of the sugar. Cover with aluminum foil and bake at 180ºC or about 20 minutes, or until apples are tender. Beat egg whites with salt until stiff. Gradually add the remaining sugar to make a stiff meringue. Spread meringue over apples to the edge of dish. Bake an additional 10 minutes, or until meringue is brown. Serve warm. Cream may be added if desired.