Place the water and rice into a saucepan, and bring to a boil over medium-high heat. Stir, and reduce heat to low. Cover pan, and simmer until all water is absorbed, about 20 minutes.

Preheat oven to 350 degrees F (175 degrees C).

Beat the egg yolks together with 1/2 cup sugar in a mixing bowl. Add the cornstarch and salt. Continue beating, and gradually pour in the milk. Stir in the cooked rice, lemon juice, and raisins. Pour the rice mixture into a baking dish, and place inside a larger baking pan. Fill the larger pan with water to 1 inch up the sides of the dish containing the rice mixture.

Bake in preheated oven until the pudding is creamy and most of the liquid is absorbed, stirring occasionally. If necessary, add more water to maintain the water level.

Meanwhile, place the egg whites in a mixing bowl and beat until soft peaks form. Continue beating, and gradually add 1/4 cup sugar. Beat until stiff peaks form. Remove the pudding from the oven, leaving it in the larger baking dish. Top pudding with the meringue, swirling with a spoon to create soft peaks.

Preheat oven to 400 degrees F (200 degrees C).

Bake in preheated oven until the meringue is golden, 8 to 10 minutes. Serve warm.