We were now entering a part of the stream which ran between broken cliffs; on one side rocks rose almost perpendicularly from the water, their summits shaped like the parapets of ruined castles, while on the other the trees came down to the river's brink.  Kakaik reminded us that we were approaching a series of rapids; and he explained by signs that he would lead the way, and advised Mike and me to keep exactly in his course.  He and Reuben paddled on, therefore, while we followed at a little distance.  We saw them descend one of the first rapids. Immediately below this, in a turn of the river, was another, the fall in which being probably about four or five feet, was not sufficient to endanger the safety of the canoes if carefully handled.