wn system of work, all of which
will be explained to you in subsequent talks, one on water-color and
the other on charcoal, is, I am aware, peculiar, and has many
drawbacks and many shortcomings. I make bold to give these to you
because of my fifty years' experience in outdoor sketching, and
because in so doing I may encourage some one among you to begin where
I have left off and do better. The requirements are thoughtful and
well-studied selection before your brush touches your canvas; a
correct knowledge of composition; a definite grasp of the problem of
light and dark, or, in other words, _mass_; a free, sure, and
untrammelled rapidity of execution; and, last and by no means least, a
realization of what I shall express in one short compact sentence,
that _it takes two men to paint an outdoor picture: one to do the work
and the other to kill him when he has done enough_.

* * * * *

Before entering on the means and methods through which so early a
death becomes permissible I shall admit that the personal equation
will largely assert itself, and that because of it certain allowances
must be made, or rather certain variations in both grasp and treatment
will necessarily follow.

While, of course, nature is always the same, never changing and never
subservient to the whims or perceptive powers of the individual, there
are painters who will aver that they alone see her correctly and that
all the world that differs from them is wrong. One man from natural
defects may see all her greens or reds stronger or weaker than another
in proportion to the condition of his eye. Another may grasp only her
varying degrees of gray. One man unduly exaggerates the intensity of
the dark and the opposing brilliancy of the lights. Another eye--for
it is largely a question of optics, of optics and temperament--sees
only the more gentle and sometimes the more subtle gradations of light
and shade reducing even the blaze of the noonday sun to half-tones.
Still another, whether by the fault of over-magnifying power or
long-sightedness, detects an infinity of detail in nature, and is not
satisfied until each particular blade of grass stands on end like the
quills of the traditional porcupine, while his brother brush
strenuously asserts that every detail is really only a question of
mass, and should be treated as such, and that for all practical
purposes it is quite immaterial whether a tree can be distinguished
f