down the
valleys of Kern and King's rivers by the lofty protective spurs
outspread embracingly above the warm Sequoia-filled basins of the Kaweah
and Tule. Then, next northward, occurs the wide Sequoia-less channel, or
basin, of the ancient San Joaquin and King's River _mer de glace_;
then the warm, protected spots of Fresno and Mariposa groves; then the
Sequoia-less channel of the ancient Merced glacier; next the warm,
sheltered ground of the Merced and Tuolumne groves; then the
Sequoia-less channel of the grand ancient _mer de glace_ of the
Tuolumne and Stanislaus; then the warm old ground of the Calaveras and
Stanislaus groves. It appears, therefore, that just where, at a certain
period in the history of the Sierra, the glaciers were not, there the
Sequoia is, and just where the glaciers were, there the Sequoia is not.

What the other conditions may have been that enabled Sequoia to
establish itself upon these oldest and warmest portions of the main
glacial soil-belt, I cannot say. I might venture to state, however, in
this connection, that since the Sequoia forests present a more and more
ancient aspect as they extend southward, I am inclined to think that the
species was distributed from the south, while the Sugar Pine, its great
rival in the northern groves, seems to have come around the head of the
Sacramento valley and down the Sierra from the north; consequently, when
the Sierra soil-beds were first thrown open to preemption on the melting
of the ice-sheet, the Sequoia may have established itself along the
available portions of the south half of the range prior to the arrival
of the Sugar Pine, while the Sugar Pine took possession of the north
half prior to the arrival of Sequoia.

But however much uncertainty may attach to this branch of the question,
there are no obscuring shadows upon the grand general relationship we
have pointed out between the present distribution of Sequoia and the
ancient glaciers of the Sierra. And when we bear in mind that all the
present forests of the Sierra are young, growing on moraine soil
recently deposited, and that the flank of the range itself, with all its
landscapes, is new-born, recently sculptured, and brought to the light
of day from beneath the ice mantle of the glacial winter, then a
thousand lawless mysteries disappear, and broad harmonies take their
places.

But although all the observed phenomena bearing on the post-glacial
history of this colossal tree point to