Our warm canyon camp is also a good place to give a thought to the glaciers which still exist at the heads of the highest tributaries. Some of them are of considerable size, especially those on the Wind River and Sawatch ranges in Wyoming and Colorado. They are remnants of a vast system of glaciers which recently covered the upper part of the Colorado basin, sculptured its peaks, ridges, and valleys to their present forms, and extended far out over the plateau region—how far I cannot now say. It appears, therefore, that, however old the main trunk of the Colorado may be, all its widespread upper branches and the landscapes they flow through are new-born, scarce at all changed as yet in any important feature since they first came to light at the close of the Glacial Period.

The so-called Grand Colorado Plateau, of which the Grand Canyon is only one of the well-proportioned features, extends with a breadth of hundreds of miles from the flanks of the Wahsatch and Park Mountains to the south of the San Francisco Peaks. Immediately to the north of the deepest part of the canyon it rises in a series of subordinate plateaus, diversified with green meadows, marshes, bogs, ponds, forests, and grovy park valleys, a favorite Indian hunting ground, inhabited by elk, deer, beaver, etc. But far the greater part of the plateau is good sound desert, rocky, sandy, or fluffy with loose ashes and dust, dissected in some places into a labyrinth of stream-channel chasms like cracks in a dry clay-bed, or the narrow slit crevasses of glaciers—blackened with lava flows, dotted with volcanoes and beautiful buttes, and lined with long continuous escarpments—a vast bed of sediments of an ancient sea-bottom, still nearly as level as when first laid down after being heaved into the sky a mile or two high.

Walking quietly about in the alleys and byways of the Grand Canyon city, we learn something of the way it was made; and all must admire effects so great from means apparently so simple; rain striking light hammer blows or heavier in streams, with many rest Sundays; soft air and light, gentle sappers and miners, toiling forever; the big river sawing the plateau asunder, carrying away the eroded and ground waste, and exposing the edges of the strata to the weather; rain torrents sawing cross-streets and alleys, exposing the strata in the same way in hundreds of sections, the softer, less resisting beds weathering and receding faster, thus undermining the harder beds, which fall, not only in small weathered particles, but in heavy sheer-cleaving masses, assisted down from time to time by kindly earthquakes, rain torrents rushing the fallen material to the river, keeping the wall rocks constantly exposed. Thus the canyon grows wider and deeper. So also do the side canyons and amphitheaters, while secondary gorges and cirques gradually isolate masses of the promontories, forming new buildings, all of which are being weathered and pulled and shaken down while being built, showing destruction and creation as one. We see the proudest temples and palaces in stateliest attitudes, wearing their sheets of detritus as royal robes, shedding off showers of red and yellow stones like trees in autumn shedding their leaves, going to dust like beautiful days to night, proclaiming as with the tongues of angels the natural beauty of death.

Every building is seen to be a remnant of once continuous beds of sediments,—sand and slime on the floor of an ancient sea, and filled with the remains of animals,—and every particle of the sandstones and limestones of these wonderful structures to be derived from other landscapes, weathered and rolled and ground in the storms and streams of other ages. And when we examine the escarpments, hills, buttes, and other monumental masses of the plateau on either side of the canyon, we discover that an amount of material has been carried off in the general denudation of the region compared with which even that carried away in the making of the Grand Canyon is as nothing. Thus each wonder in sight becomes a window through which other wonders come to view. In no other part of this continent are the wonders of geology, the records of the world's auld lang syne, more widely opened, or displayed in higher piles. The whole canyon is a mine of fossils, in which five thousand feet of horizontal strata are exposed in regular succession over more than a thousand square miles of wall-space, and on the adjacent plateau region there is another series of beds twice as thick, forming a grand geological library—a collection of stone books covering thousands of miles of shelving, tier on tier, conveniently arranged for the student. And with what wonderful scriptures are their pages filled—myriad forms of successive floras and faunas, lavishly illustrated with colored drawings, carrying us back into the midst of the life of a past infinitely remote. And as we go on and on, studying this old, old life in the light of the life beating warmly about us, we enrich and lengthen our own.

THE END

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