Sec. 1. Having in the preceding chapter seen the grounds on which to explain and justify Turner's _choice_ of facts, we proceed to examine finally those modes of _representing_ them introduced by him;--modes so utterly at variance with the received doctrines on the subject of art, as to cause his works to be regarded with contempt, or severe blame, by all reputed judges, at the period of their first appearance. And, chiefly, I must confirm and farther illustrate the general statements made respecting light and shade in the chapters on Truth of Tone,[13] and on Infinity,[14] deduced from the great fact (Sec. 5. chapter on Truth of Tone) that "nature surpasses us in power of obtaining light as much as the sun surpasses white paper." I found that this part of the book was not well understood, because people in general have no idea how much the sun _does_ surpass white paper. In order to know this practically, let the reader take a piece of pure white drawing-paper, and place it in the position in which a drawing is usually seen. This is, properly, upright (all drawings being supposed to be made on vertical planes), as a picture is seen on a room wall. Also, the usual place in which paintings or drawings are seen is at some distance from a window, with a gentle side light falling upon them, front lights being unfavorable to nearly all drawing. Therefore the highest light an artist can ordinarily command for his work is that of white paint, or paper, under a gentle side light.[15] But if we wished to get as much light as possible, and to place the artist under the most favorable circumstances, we should take the drawing near the window. Put therefore your white paper upright, and take it to the window. Let _ac_, _cd_, be two sides of your room, with a window at _bb_. Under ordinary circumstances your picture would be hung at _e_, or in some such position on the wall _cd_. First, therefore, put your paper upright at _e_, and then bring it gradually to the window, in the successive positions _f_, _g_, and (opening the window) finally at _p_. You will notice that as you come nearer the window the light gradually _increases_ on the paper; so that in the position at _p_ it is far better lighted than it was at _e_. If, however, the sun actually falls upon it at _p_, the experiment is unfair, for the picture is not meant to be seen in sunshine, and your object is to compare pure white paper, as ordinarily used, _with_ sunshine. So either take a time when the sun does not shine at all, or does not shine in the window where the experiment is to be tried; or else keep the paper so far within the window that the sun may not touch it. Then the experiment is perfectly fair, and you will find that you have the paper at _p_ in full, serene, pictorial light, of the best kind, and highest attainable power. [Illustration: FIG. 2.]