y they discovered also a smaller ruin,
which they named Spruce Tree House, because a prominent spruce grew in
front of it. These are the largest two cliff-dwellings in the Mesa Verde
National Park, and, until Doctor J. Walter Fewkes unearthed Sun Temple
in 1915, among the most extraordinary prehistoric buildings north of
Mexico.

There are thousands of prehistoric ruins in our southwest, and many
besides those of the Mesa Verde are examples of an aboriginal
civilization. Hundreds of canyons tell the story of the ancient
cliff-dwellers; and still more numerous are the remains of communal
houses built of stone or sun-dried brick under the open sky. These
pueblos in the open are either isolated structures like the lesser
cliff-dwellings, or are crowded together till they touch walls, as in
our modern cities; often they were several stories high, the floors
connected by ladders. Sometimes, for protection against the elements,
whole villages were built in caves. Pueblos occasionally may be seen
from the car-window in New Mexico. The least modified of the prehistoric
type which are occupied to-day are the eight villages of the Hopi near
the Grand Canyon in Arizona; a suggestive reproduction of a model
pueblo, familiar to many thousands who have visited the canyon, stands
near the El Tovar Hotel.

It was not therefore because of the rarity of prehistoric dwellings of
either type that the cliff villages of the Mesa Verde were conserved as
a national park, nor only because they are the best preserved of all
North American ruins, but because they disclose a type of this culture
in advance of all others.

The builders and inhabitants of these dwellings were Indians having
physical features common to all American tribes. That their
accomplishment differed in degree from that of the shiftless war-making
tribes north and east of them, and from that of the cultured and
artistic Mayas of Central America, was doubtless due to differences in
conditions of living. The struggle for bare existence in the southwest,
like that of the habitats of other North American Indians, was intense;
but these were agriculturalists and protected by environment. The desert
was a handicap, of course, but it offered opportunity in many places for
dry farming; the Indian raised his corn. The winters, too, were short.
It is only in the southwest that enterprise developed the architecture
of stone houses which distinguish pueblo Indians from others in North