Sift together flour, baking powder, sugar, and salt. In a separate bowl, whisk together the eggs and 1 1/2 cups of milk; add to flour mixture, stirring only until smooth. Blend in melted butter. If the batter seems too thick to pour, add a little more milk. Cook on a hot, greased griddle, using about 1/4 cup of batter for each pancake. Cook until bubbly, a little dry around the edges, and lightly browned on the bottom; turn and brown the other side. Recipe for pancakes serves 4.