The sound was a short, heavy moan, as nearly as it may be described, and not a sharp rending note; a vast, deep groan, somewhere deep in the earth, as though a volcano were about to erupt. It was not over in an instant, but went on, like the suppressed lamentations of some creature trying to break its chains. It might have been some prehistoric, tremendous creature, unknown to man, unknown to these times. But it was our creature. It was of our day. Else it could never have been. Then the ground under the feet of every man on the little street lifted, gently, slowly, and sank down again. As it did so a tremendous reverberation gathered and broke out, ran up and down the canyon, up the opposite cliff face, echoing and rising as dense and thick as smoke does. The rack-rock charge, of no one may know how many hundreds of pounds, had done its work. And then all earth went back to chaos. A new world was in the making. There arose in that narrow, iron-sided gorge a havoc such as belike surpassed that of the original breaking through of the waters. That first slow work of nature might have been done drop by drop, a little at a time. But now all the outraged river was venting itself in one epochal instant. Its accumulated power was rushing through the wall that held it back from the seas--the vast vengeance of the waters, which they had sought covertly all this time, now was theirs. An uncontrollable and immeasurable force was set loose. No man may measure the actual horse power that lay above the great dam of the Two Forks--it never was a comprehensible thing. A hundred Johnstown reservoirs lay penned there. That there was so little actual loss of life was due to the fact that there were few settlements in the sixty miles below the mouth of the great canyon itself. A few scattered dry farms, edging up close to the river in the valley far below, were caught and buried. Hours later, under the advancing flood, all the live stock of the valley was swept away, all the houses and all the fences and roads and bridges were wiped out as though they had never been. But this was fifty, sixty, seventy miles away, and much later in the morning. Those below could only guess what had happened far up in the great Two Forks canyon. The big dam was broken! The face of the giant dam, more solidly coherent than granite itself, slowly, grandiose even in its ruin, passed out and down in a hundred foot crevasse where the spill gates were widened by the high explosive. A vast land slip, jarred from the cut-face mountain side above, thundered down and aided in the crumbling of the dam. A disintegrated mass of powdered concrete fell out, was blown apart. The face of the dam on that part slowly settled down into a vast U. Then the waters came through, leaping--a solid face of water such as no man may comprehend.