The Grand Cañon of the Colorado is a masterpiece of erosion--a wonderful story carved in rock. It was excavated and washed out by the river. It is not an ordinary mountain cañon, for it lies in a comparatively level plain or plateau. During the ages, the débris-laden water sliding over its inclined bed of solid rock dug, sawed, and cut the cañon to the bottom. The river not only carried away all the material worn from the bottom, but the thousandfold more that tumbled into it from the ever-caving walls. Here is color in magnificent array. Most of the strata are perfectly horizontal and of great thickness, and each has an individual color. Many of the walls are brown or red, and there are strata of gray, yellow, grayish brown, and grayish green. All these are massed and arranged in vast and broken color pictures and landscapes, some of which are a mile high and several miles in length. The top, or rim, of the cañon is in an extensive arid region. Water is extremely scarce; in a number of places not a drop is available within miles. If a boatman is wrecked in the cañon, he has little opportunity of escaping. If he should manage to climb out on the desolate, almost uninhabited plateau, he would be likely to perish for lack of water. The cañon has a climate of its own. In the bottom, the temperature frequently shows a range of one hundred degrees inside of twenty-four hours. Its great depth and peculiar wall exposure give it a climatic variety. The walls that face the north are much cooler than those facing the south. The temperature at the top differs from that at the bottom, and midway on the walls is a temperature distinct from either of the others. On the rim at El Tovar it may be a winter day; you descend to the river and there find a mild climate, with birds singing and flowers in bloom. The six thousand feet of descent to the river gives a climatic change that approximates a southern journey of two thousand miles. This plateau is forested and on the northern rim of the cañon the tree-growth is heavy. Flowers bloom in the cañon every month in the year. In the niches and on the terraces are the columbine, lupine, stonecrop, kinnikinnick, dandelion, thistle, and paintbrush. Sagebrush and greasewood occur in many places. The Douglas spruce is found upon the southern wall, the cottonwood and willow in the bottom. Beavers, a few deer, many rabbits, wildcats, and wolves are found in a few places in the bottom of the cañon, and sheep and lions upon the terraces. But the larger part of the unbroken and terraced walls is barren and lifeless. Among the birds that gladden this gorge are the mockingbird, piñon jay, robin, quail, hummingbird, kingfisher, swallow, and owl. Here, too, you will hear that melodious and hopeful singer the cañon wren. Over this vast gulf butterflies with daintily colored wings float in lovely laziness.