Allow butter and eggs to stand at room temperature for 30 minutes.
Meanwhile, grease a 10-inch tube or bundt pan; set aside.
In a large bowl sift together the flour, baking powder and salt; set aside.
In a very large mixing bowl, beat the butter and sugar with an electric mixer, on medium speed, until mixture is well combined; beat in eggs.
Add flour, baking powder and salt mixture to the butter, sugar and eggs mixture.
Stir in just enough milk to combine.
By hand, stir blueberries into mixture.
Spread batter in prepared pan.
Place in pre-heated oven and bake for 60 to 75 minutes or until a wooden skewer, inserted near center, comes out clean.
Remove from oven and allow to cool, on a wire rack, for 15 minutes.
Loosen cake from edge of pan with a narrow plastic spatula.
Remove cake from pan; cool completely on wire rack.
Notes
This is excellent all by itself, but would be great with a little added lemon zest or a couple handfuls of white chocolate chips. Or maybe a mixture of blueberries and raspberries.