About 3 miles from its mouth De Chelly is joined by another canyon almost as long, which, heading also in the Tunicha mountains, comes in from the northeast. It is over 15 miles long, and is called on the map Canyon del Muerto; the Navaho know it as En-a-tse-gi. About 13 miles above the mouth of the main canyon a small branch comes in from the southeast. It is about 10 miles long, and has been called Monument canyon, on account of the number of upright natural pinnacles of rock in it. In addition to those named there are innumerable small branches, ranging in size from deep coves to real canyons a mile or two long. Outside of De Chelly, and independent of it, there is a little canyon about 4 miles long, called Tse-on-i-tso-si by the Navaho. At one point near its head it approaches so near to De Chelly that but a few feet of rock separate them. On the western side of the mountains there are a number of small perennial streams fed by springs on the upper slopes. Several of these meet in the upper part of De Chelly, others in Del Muerto, and in the upper parts of these canyons there is generally water. But, except at the time of the autumn and winter rains and in the spring when the mountain snows are melting, the streams are not powerful enough to carry the water to the mouth of the canyon. The flow is absorbed by the deep sand which forms the stream bed. Ordinarily it is difficult to procure enough water to drink less than 8 or 10 miles from the mouth of De Chelly, but occasionally the whole stream bed, at places over a quarter of a mile wide, is occupied by a raging torrent impassable to man or beast. Such ebullitions, however, seldom last more than a few hours. Usually water can be obtained anywhere in the bottom by sinking a shallow well in the sand, and it is by this method that the Navaho, the present occupants of the canyon, obtain their supply. The walls of the canyon are composed of brilliant red sandstone, discolored everywhere by long streaks of black and gray coming from above. At its mouth it is about 500 feet wide. Higher up the walls sometimes approach to 300 feet of each other, elsewhere broadening out to half a mile or more; but everywhere the wall line is tortuous and crooked in the extreme, and, while the general direction of De Chelly is east and west, the traveler on the trail which runs through it is as often headed north or south. Del Muerto is even more tortuous than De Chelly, and in places it is so narrow that one could almost throw a stone across it.