In a large bowl,stir together flour,baking powder,salt,baking soda;make a well in the center and set aside.
Stir together butter and boiling water until butter is melted.
In a medium bowl,combine egg,sugar,orange juice;stir in butter mixture.
Add to dry ingredients,stirring just until moistened.
Fold in Blueberries.
Spoon the batter into the prepared pan.
Bake 350 about 60 minutes,or until a toothpick comes clean when inserted near the center.
Cool 10 minutes.
Remove from pan and cool completely on rack.
Wrap in aluminum foil and store overnight.