Prepare for this recipe by setting aside 3 tin cans (1 pound 4 ounce size).
Grease the insides and bottoms of the empty cans well; Stir eggs, butter, and molasses together.
In a 2 cup measure, mix baking soda with buttermilk.
Sift together white flour, baking powder, salt, and whole-wheat flour.
Alternately add buttermilk mixture and flour to egg mixture.
Last, add raisins; stir well.
Fill the waiting tin cans half full; cover tightly with foil.
Put 4 cups water and the rack in cooker.
Set the cans on rack; close cover securely.
Do not put pressure control on.
Allow a small stream of steam to escape from cooker for 1 1/2 hours.
Remove cooker from heat.
Let stand 5 minutes more, then open.
Your loaves are ready for butter or cream cheese.