at the first
glance was clear, is now dotted with passers-by, thus obscuring your
point of interest, or a cloud has passed over the sky, lowering the
whole tone, or the group of figures across the light has dispersed,
exposing the ugly right-angled triangle of the flat wall and street
level instead of the same lines being broken picturesquely with the
black dots of heads of the crowd itself. In a moment it is no longer a
composition of the same power that struck you at first. Perhaps while
you sit and wait the scene again changes, and something infinitely
more interesting, or the reverse, is evolved from the perspective
before you. And so it goes on, until this constantly changing
kaleidoscope repeats itself in its first aspect, until you have fairly
grasped its meaning and analyzed its component parts. Or until either
the effect that first delighted you, or the subsequent effect that
charmed you still more, becomes a fixed fact in your mind. That, then,
is the picture that you want to paint and that you are to paint
_exactly as you saw it_. And if you can reproduce it exactly as you
did see it, ten chances to one it will impress your fellow men. The
trouble is that when you sit down to paint it you are so often lost in
its detail that you forget its salient features, and by the time you
have finished and blocked up the immediate foreground with figures
that did not exist when you were first thrilled by its beauty, you
have either painted its least interesting aspect, or you have filled
that street so full of lies of your own that the policeman on the beat
could not recognize it.

Of course, while all nature is interesting, there are parts of nature
more interesting than other parts, and since the skill of man is
inadequate to produce its more _humble_ effects, if I may so express
it, the painter should be on the lookout for her _dramatic_ air, in
order that when she is reproduced she may add that touch to her many
qualities, thus meeting the painter half-way. Even in the perspective
of a street, nature, in profound consideration of the devotee under
his umbrella, often gives him a deeper touch--one wall perhaps in
sudden brilliant light, while the vista of the street is in gloom made
by a passing cloud, she constantly calling out to the painter as he
works: "Watch me now and take me at my best."

Or change this picture for an instant and note, if you please, the
flight of cloud shadows over a mountain slope or the wh