The Colorado and its tributaries drain nearly the whole of Arizona, and it is one of the most remarkable rivers in the world. Its head branches have their sources in Wyoming, Colorado and Utah, uniting in the latter State, flowing four hundred miles across Arizona and seventy miles into Mexico to discharge through a delta into the Gulf of California. The river and most of its tributaries in Arizona pass through canyons that are among the wonders of the world, exposing to view geological strata of all the formations in their regular places to the thickness of twenty-five thousand feet. At first, the Colorado flows out of Utah and south into Arizona for one hundred and eighty miles, passing through the Marble Canyon, so called from the limestone walls, nearly four thousand feet deep. It then turns westward by irregular course, flowing nearly two hundred and fifty miles through the Grand Canyon, the most stupendous in existence, and having at places six thousand feet depth and walls spreading at the surface five or six miles apart. These huge walls are terraced and carved into myriads of pinnacles and towers, often brilliantly colored, and far down in the bottom the river is seen like a silvery thread of foam. Major Powell, who first explored it in 1869, went through in a boat. He calls it "the most profound chasm known on the globe," and believes the river was running there before the mountains were formed, and that the canyon was made by the erosion of the water acting simultaneously with the slow upheaval of the rocks. The river has a rapid flow in the canyon, winding generally through a lower chasm and having a descent of five to twelve feet to the mile, sometimes with placid reaches, but frequently plunging down rapids filled with rocks. The surrounding country is largely volcanic, with lava-beds and extinct craters. When the visitor first approaches the brink of the great chasm, he is almost appalled with the sight. There seem to be scores of deep ravines and enclosed mountains, the main wall opposite being miles away, and the intervening space filled with peaks and ridges of every imaginable shape and color, rising from the abyss below. There is a trail down the side of the canyon, a steep and narrow path winding along the face of the Grand View Gorge, giving startling glimpses into ravines thousands of feet deep, and disclosing the massive magnificence of this enormous abyss. Down goes the trail, one gorge opening below another until the verge of the final gorge is reached, in which the river runs at a depth of a thousand feet farther. Everything is desolate, the vegetation sparse, and a few stunted trees appearing, while the river, which seemed from above to be only a far distant silvery streak down below, is expanded by the nearer view into large proportions. This Grand Canyon of the Colorado is one of the most wonderful constructions of nature in its stupendous size and extraordinary character; with the myriads of pinnacles, towers,