Twice he stepped on her foot, and again his broad chest hit her shoulder and threw her flat.

When he began to slide, near the bottom, Helen had to run for her life.
"Oh, Nell! Isn't--this--great ?" panted Bo, from somewhere ahead.
"Bo--your--mind's--gone," panted Helen, in reply.
Roy tried several places to climb out, and failed in each.

Leading down the ravine for a hundred yards or more, he essayed another attempt.
Here there had been a slide, and in part the earth was bare.

When he had worked up this, he halted above, and called: "Bad place! Keep on the up side of the hosses!" This appeared easier said than done.

Helen could not watch Bo, because Ranger would not wait.