two hundred and sixteen years before its death;
another which it received in 1830; and a fourth which it received
fourteen years before it blew over in the autumn of 1892. All of these
fire-scars were on the same quarter of the tree. All were on that part
of the tree which overlooked the down-sloping hillside.

Forest fires, where there is opportunity, sweep up the mountain-side
against the lower side of the trees. The lower side is thus often
scarred while the opposite side is scarcely injured; but wind blowing
down the gulch at the time of each fire may have directed the flames
against the lower side of this tree. In many places clusters of young
trees were growing close to the lower side of the old trees, and were
enabled to grow there by light that came in from the side. It may be
that the heat from one of the blazing clusters scarred this old pine;
then another young cluster may have grown, to be in time also
consumed. But these scars may have resulted, wholly or in part, from
other causes.

Yellow pine claims the major portion of the well-drained slopes,
except those that are northerly, in the middle mountain-zone up to
the lower lodge-pole margin. A few groves are found higher than nine
thousand feet. Douglas spruce covers many of the northerly slopes
that lie between six thousand and nine thousand feet.

The regularity of tree-distribution over the mountains is to me a
never-failing source of interest. Though the various species of trees
appear to be growing almost at random, yet each species shows a
decided preference for peculiar altitude, soil, temperature, and
moisture conditions. It is an interesting demonstration of tree
adaptability to follow a stream which comes out of the west, in the
middle mountain-zone, and observe how unlike the trees are which
thrive on opposite sides. On the southerly slopes that come down to
the water is an open forest of yellow pine, and on the opposite side,
the south bank, a dense forest of Douglas spruce. If one be told the
altitude, the slope, and the moisture conditions of a place on the
Rockies, he should, if acquainted with the Rockies, be able to name
the kinds of trees growing there. Some trees grow only in moist
places, others only in dry places, some never below or above a certain
altitude. Indeed, so regular is the tree-distribution over the Rockies
that I feel certain, if I were to awaken from a Rip Van Winkle sleep
in the forests on the middle or upper slopes of