asked in classical times by
ingenious puzzle-makers--"What is the size of the moon?" A true answer
to that question would be "that of a plate a foot in diameter seen at
a distance of a hundred and fifteen feet."

To a large extent the painter, like other artists, has to produce
things which do not shock common opinion and experience, and must even
consciously concede to that necessity, and make the sacrifice of
objective truth, in order to secure attention for his higher appeal to
the sense of beauty, to emotion, and sentiment. Approved departures by
the artist from scientific truth are those which are deliberately made
in order to give emphasis--as, for instance, in the huge, but tender
hand of the man in the emotional masterpiece, "Le Baiser," by the
great sculptor Rodin. Another departure from objective truth which is
justified, is seen in Troyon's picture in the Louvre, where the false
drawing and exaggerated size of the leg of a calf advancing towards
the observer suggest, and almost give the illusion of, movement.

But it can hardly be maintained that any and all the liberties which a
painter or a whole school of painters choose to take with fact in
their presentation of Nature--are beyond criticism. It is possible for
a landscape painter to improve in his treatment of the moon by better
observation and increased knowledge--just as other painters have
learnt not to introduce into their pictures the sort of wooden
rocking-horse to stand for a beautiful living animal, which satisfied
Velasquez, Carl Vernet and the ancient Egyptians.

FOOTNOTES:

[Footnote 1: See note on page 46.]

[Footnote 2: "La Representation du Galop dans l'art ancien et
moderne," 'Revue Archeologique,' vol. XXXVI _et seq._, 1900.]

[Footnote 3: A word is needed in amplification of what was said on p.
26 as to the blending of successive images produced on the retina of
the eye by the bioscope or cinematograph or by the old "wheel of
life." The point which is of importance is not the length of time
during which the stimulation of the retina caused by an image
_endures_--becoming weaker and weaker as fractions of a second
pass--but it is this: How long will a stimulus last in _undiminished
brightness_? How soon must it be followed by another stimulus (another
image) so that there may be fusion or continuity, the one succeeding
the other before the earlier has had time, not to disappear, but to
decline. If it has had time to decline in inten