The amount of milk you use here determines the thickness of the pancakes, so start slow.
Slightly adapted from The Fanny Farmer Cookbook
Beat the milk, butter and egg lightly in a medium-sized bowl. In a separate bowl, mix the flour, baking powder, sugar and salt and add them all at once to the first mixture, stirring just enough to dampen the flour. Add blueberries and stir to combine. Lightly butter a griddle and over medium heat, pour about ¼ cup (for larger griddlecakes) of batter to form each pancake.