Mix all ingredients, adding more milk if needed to make dough firm.  Roll out onto floured surface to a 1/2-inch thickness.  Use any shape cookie cutter to cut out biscuits, but bone shapes are fun!  Bake on ungreased baking sheets at 350 degrees for 30 minutes or until lightly toasted.  To make biscuits harder, leave in oven with the heat turned off for an hour or more.