That it had been a water course was evidenced by the beds of well worn gravel, devoid of all soil, and the marks of the constant wash of the waves on the face of the cliffs on either side. Who knows but what at some remote period the mighty Columbia river had flowed through this grand coulee, emptying into an inland sea, the bed of which now formed the desert of almost a million acres, destined to be the home of half as many people? Flowing thus for ages, nourishing plants now unknown; its limpid waters, cooling and refreshing the prehistoric monsters that came daily to drink at its brink; sheltering beneath its rippling waves species of fish now extinct, their fossalized forms only remaining to remind us of the mighty changes that have taken place. Flowing peacefully on, secure in its mightiness, yet all the while somewhere along its course was being assembled the power that wrought this change, the terrific force in the nature of gases generated far in the depths of the earth. It might be thousands of miles away, conducted through unknown channels and crevices, seeking the point of least resistance, forced hither and thither by the ever increasing pressure, until a subterranean cavity is formed by a slight upheaval or displacement of the stratification. Into this rush the gases, followed by the raging fires, until further resistance is impossible. The imprisoned demon crouches in narrow confines, trapped at last; and with a mighty shudder, the effects of which are felt on the surface, causing the ponderous mastodon to halt unsteadily, and raising his gigantic head in alarm, sounds a note of warning, and followed by his herd, rushes madly through the mass of huge ferns in search of safety. The imprisoned force, no longer able to confine its strength, furiously gathers its reenforcement, and with terrific, thunderous roar, forces the crust and breaks through, tearing asunder this sphere that has taken eons to form, disgorging in fiery torrents upon the surface of half a continent the contents of its seething cauldron.