It is a great error in some painters who draw a figure from Nature at home, by any particular light, and afterwards make use of that drawing in a picture representing an open country, which receives the general light of the sky, where the surrounding air gives light on all sides. This painter would put dark shadows, where Nature would either produce none, or, if any, so very faint as to be almost imperceptible; and he would throw reflected lights where it is impossible there should be any.