July 30.--We make good progress to-day, as the water, though smooth, is swift. Sometimes the canyon walls are vertical to the top; sometimes they are vertical below and have a mound-covered slope above; in other places the slope, with its mounds, comes down to the water's edge.
Still proceeding on our way, we find that the orange sandstone is cut in two by a group of firm, calcareous strata, and the lower bed is under-
laid by soft, gypsiferous shales. Sometimes the upper homogeneous bed is a smooth, vertical wall, but usually it is carved with mounds, with gently meandering valley lines. The lower bed, yielding to gravity, as the softer shales below work, out into the river, breaks into angular surfaces, often having a columnar appearance. One could almost imagine that the walls had been carved with a purpose, to represent giant architectural forms. In the deep recesses of the walls we find springs, with mosses and ferns on the moistened sandstone.
July 31.--We have a cool, pleasant ride to-day through this part of the canyon. The walls are steadily increasing in altitude, the curves are gentle, and often the river sweeps by an arc of vertical wall, smooth and unbroken, and then by a curve that is variegated by royal arches, mossy alcoves, deep, beautiful glens, and painted grottoes. Soon after dinner we discover the mouth of the San Juan, where we camp. The remainder of the afternoon is given to hunting some way by which we can climb out of the canyon; but it ends in failure.
August 1.--We drop down two miles this morning and go into camp again. There is a low, willow-covered strip of land along the walls on the east. Across this we walk, to explore an alcove which we see from the river. On entering, we find a little grove of box-elder and cotton-wood trees, and turning to the right, we find ourselves in a vast chamber, carved out of the rock. At the upper end there is a clear, deep pool of water, bordered with verdure. Standing by the side of this, we can see the grove at the entrance. The chamber is more than 200 feet high, 500 feet long, and 200 feet wide. Through the ceiling, and on through the rocks for a thousand feet above, there is a narrow, winding skylight; and this is all carved out by a little stream which runs only during the few showers that fall now and then in this arid country. The waters from the bare rocks back of the canyon, gathering rapidly into a small channel, have eroded a deep side canyon, through which they run until they fall into the farther end of this chamber. The rock at the ceiling is hard, the rock below, very soft and friable; and having cut through the upper and harder portion down into the lower and softer, the stream has washed out these friable sandstones; and thus the chamber has been excavated.
Here we bring our camp. When "Old Shady" sings us a song at
FROM THE GRAND TO THE LITTLE COLORADO.