Cream the butter and sugar, and add in the eggs one at a time. Add in the flour, baking powder, salt (which have been sifted together), and then the orange rind and orange juice. If the mix is too stiff, add in a bit of milk or more orange juice, but the mix should be stiff to hold their shape. Bake in a preheated 375 degree oven until they are very lightly browned.