escape from us as we try to
shape them, each, in its stealthy minute march, still leaving light
where its tremulous edge had rested the moment before, and involving in
eclipse objects that had seemed safe from its influence; and instead of
the small clusters of leaves which we could reckon point by point,
embarrassing enough even though numerable, we have now leaves as little
to be counted as the sands of the sea, and restless, perhaps, as its
foam.

103. In all that we have to do now, therefore, direct imitation becomes
more or less impossible. It is always to be aimed at so far as it _is_
possible; and when you have time and opportunity, some portions of a
landscape may, as you gain greater skill, be rendered with an
approximation almost to mirrored portraiture. Still, whatever skill you
may reach, there will always be need of judgment to choose, and of speed
to seize, certain things that are principal or fugitive; and you must
give more and more effort daily to the observance of characteristic
points, and the attainment of concise methods.

104. I have directed your attention early to foliage for two reasons.
First, that it is always accessible as a study; and secondly, that its
modes of growth present simple examples of the importance of leading or
governing lines. It is by seizing these leading lines, when we cannot
seize all, that likeness and expression are given to a portrait, and
grace and a kind of vital truth to the rendering of every natural form.
I call it vital truth, because these chief lines are always expressive
of the past history and present action of the thing. They show in a
mountain, first, how it was built or heaped up; and secondly, how it is
now being worn away, and from what quarter the wildest storms strike it.
In a tree, they show what kind of fortune it has had to endure from its
childhood: how troublesome trees have come in its way, and pushed it
aside, and tried to strangle or starve it; where and when kind trees
have sheltered it, and grown up lovingly together with it, bending as it
bent; what winds torment it most; what boughs of it behave best, and
bear most fruit; and so on. In a wave or cloud, these leading lines show
the run of the tide and of the wind, and the sort of change which the
water or vapor is at any moment enduring in its form, as it meets shore,
or counter-wave, or melting sunshine. Now remember, nothing
distinguishes great men from inferior men more than their always,