the Tunicha mountains. The summit here is a sharp ridge with pronounced
slopes and is from 9,000 to 9,400 feet high. On the west there are
numerous small streams, which, rising near the summit, course down the
steep slopes and finally discharge through Canyon Chelly into the great
Chinlee valley, which is the western of the two valleys referred to
above. The eastern slope is more pronounced than the western, and its
streams are so small and insignificant that they are hardly worthy of
mention.

Still farther to the northwest, and not separated from the Tunicha
except by a drawing in or narrowing of the mountain mass, with no
depression of the summit, is another part of the same range, which bears
a separate name. It is known as the Lukachukai mountains. Here something
of the range character is lost, and the uplift becomes a confused mass,
a single great pile, with a maximum altitude of over 9,400 feet.

Northwest of this point the range breaks down into Chinlee valley, but
directly to the north is another uplift, called the Carriso mountains.
It is a single mass, separated from the range proper by a comparatively
low area of less than 7,000 feet altitude, while the Carriso itself is
over 9,400 feet above the sea.

The western and northwestern parts of the reservation might also
be classed as mountainous. Here there is a great mesa or elevated
table-land, cut and gashed by innumerable canyons and gorges, and with
a general elevation of 7,500 to 8,000 feet. Throughout nearly its whole
extent it is impassable to wagons.

The valleys to which reference has been made are the Chinlee on the west
and the Chaco on the east of the principal mountain range described.