the boat turned it instantly upside down and cast Powell some distance away.  He succeeded in reaching her side, and there found Sumner and Dunn clinging.  When quiet water was again entered they attempted to right the craft, and in doing this Dunn lost his hold and went under, though at the critical moment, as he came up, Sumner succeeded in grasping him and drawing him to the boat.  By this time, they had drifted a long way down and saw another rapid approaching.  By swimming desperately, they avoided being carried into this in their awkward plight, and, towing the boat after them, landed none too soon on a pile of driftwood on the bank.  A gun, some barometers, and other articles that were in the open compartment, were lost, though one roll of blankets had been caught and saved by Powell as it drifted by.  Building a large fire on the shore, they dried their clothing, while out of one of the logs they manufactured much-needed oars.

Fortified by these, they ran several bad rapids the following day.  In one, Bradley was knocked overboard, but, his foot catching under the seat, he was dragged head down through the water till the worst of the fall was passed, when one of the other men managed to haul him in.  Just below this, they emerged again into an expansion of the walls, leaving the ninety-seven miles of Desolation behind.  But another mile brought the rocks back once more, and the thirty-six miles of Gray Canyon must be passed before they came to Gunnison Valley.  Beyond this, walls of sandstone about one thousand feet high hemmed the river in for some sixty miles, but the stream was not dangerous and the party moved on quickly, though the absence of rapids and swift water made rowing obligatory.  At the foot of this gorge, called from its winding character, Labyrinth Canyon, there was a brief expansion before the next walls closed upon them.  These were closer than any seen above, but the river, though swift, had no dangerous element, so that progress was safe and easy, and in a trifle over forty miles they came to the mouth of a river almost as large as the Green, flowing in a canyon of similar depth and character.  This was Grand River.  At last they had reached the place where these two streams unite, thirteen hundred feet below the surrounding country; the mysterious Junction which, so far as the records go, Macomb and all white men before had failed to find.  Therefore when Powell and his band floated down till the waters of the Green mingled with those of the Grand they were perhaps the first white men ever to arrive at the spot.  The Colorado proper was now before them.  It was the mystery of mysteries.

CHAPTER IX

A Canyon of Cataracts—­The Imperial Chasm—­Short Rations—­A Split in the Party—­Separation—­Fate of the Howlands and Dunn—­The Monster Vanquished.