Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 9x13 inch pan.
In a large bowl, cream together the butter and sugar until light and fluffy. Beat in the eggs one at a time, then stir in the vanilla.
Combine the flour, baking powder, cinnamon, nutmeg, and cloves; stir into the creamed mixture alternately with the milk.
Fold in the black walnuts. Spread evenly into the prepared pan.
Bake for 40 to 45 minutes in the preheated oven, or until a toothpick inserted into the center of the cake comes out clean.
Cool in the pan for 10 minutes, then turn out onto a wire rack and cool completely.
Interesting Facts
Pound cake is believed to have originated in the 18th century and was originally called a "pound cake" because the recipe called for one pound each of flour, butter, eggs, and sugar.
Black walnuts are native to the United States and are highly prized for their flavor.
The combination of cinnamon, nutmeg, and cloves is known as "pumpkin pie spice" and is used to flavor many desserts.