Preheat oven to 375 degrees F.
In a bowl, sift together flour, baking powder, baking soda, and nutmeg.
In another bowl, cream butter, then add salt and lemon zest, and gradually the sugar. Beat in eggs and milk, and little by little add the dry sifted ingredients.
Drop by spoonfuls on ungreased baking sheets. Sprinkle each cookie with sugar and bake for about 12 minutes.