Blueberry Cake

2 1/2 cups flour
2 1/2 teaspoons baking powder
1/2 teaspoon salt
1/2 cup butter
1 cup sugar
1 egg, unbeaten
1/2 cup milk
2 cups blueberries
1/2 teaspoon vanilla

Sift flour once, add salt and baking powder.

Cream butter and sugar, add egg and beat thoroughly. Add flour and milk, alternately, until smooth. Stir in vanilla.

Fold in berries.

Bake at 350°F for 45 minutes or until cake tests done