nd in ascending these
curves converges toward the summits, carrying the snow in concentrating
currents with it, shooting it almost straight up into the air above the
peaks, from which it is then carried away in a horizontal direction.

This difference in form between the north and south sides of the peaks
was almost wholly produced by the difference in the kind and quantity of
the glaciation to which they have been subjected, the north sides having
been hollowed by residual shadow-glaciers of a form that never existed
on the sun-beaten sides.

It appears, therefore, that shadows in great part determine not only the
forms of lofty icy mountains, but also those of the snow-banners that
the wild winds hang on them.

CHAPTER IV

A NEAR VIEW OF THE HIGH SIERRA

Early one bright morning in the middle of Indian summer, while the
glacier meadows were still crisp with frost crystals, I set out from the
foot of Mount Lyell, on my way down to Yosemite Valley, to replenish my
exhausted store of bread and tea. I had spent the past summer, as many
preceding ones, exploring the glaciers that lie on the head waters of
the San Joaquin, Tuolumne, Merced, and Owen's rivers; measuring and
studying their movements, trends, crevasses, moraines, etc., and the
part they had played during the period of their greater extension in the
creation and development of the landscapes of this alpine wonderland.
The time for this kind of work was nearly over for the year, and I began
to look forward with delight to the approaching winter with its wondrous
storms, when I would be warmly snow-bound in my Yosemite cabin with
plenty of bread and books; but a tinge of regret came on when I
considered that possibly I might not see this favorite region again
until the next summer, excepting distant views from the heights about
the Yosemite walls.

To artists, few portions of the High Sierra are, strictly speaking,
picturesque. The whole massive uplift of the range is one great picture,
not clearly divisible into smaller ones; differing much in this respect
from the older, and what may be called, riper mountains of the Coast
Range. All the landscapes of the Sierra, as we have seen, were born
again, remodeled from base to summit by the developing ice-floods of the
last glacial winter. But all those new landscapes were not brought forth
simultaneously; some of the highest, where the ice lingered longest, are
tens of centuries younger than those of th