I imagine we had progressed thus for upwards of three or four hundred yards, and were elevated so far above the stream that scarcely an echo of its noise assailed our ears even in the silence of the night, when suddenly we came to the end of our path.  The rocky shelf was so narrow the very conception of turning about smote me with terror.  Directly in front, extending to the very edge, stretched a solid wall of rock.  My eyes sank to the shelf on which I stood.  Lying close against the sheer cliff was the root of a tree, its trunk, perhaps a foot or more in diameter, stretching over the abyss, whose depth I durst not guess.  I stooped cautiously, my heart throbbing, and ran my fingers along the bark.

“Oak,” I announced soberly, “and feels solid and strong.  No doubt those Indians must cross here, but it is a bridge to rack the nerves.”

“Will you adventure the passage?” questioned Cairnes, striving to peer across my shoulder.  “As for me I would rather attempt the Red Sea.”

“Odds, man, the choice is not given.  ’T is either turn and go back, or foot the tree; of the two the attempt at turning would addle me worse.”

I leaned out over the edge as far as I dared, clinging desperately to the root, and gazed down.  It was like peering into the mouth of a great well.  Then I nerved myself for the ordeal, and the next moment was fairly launched over the abyss, hanging on grimly to the log, my brain reeling as if with drunkenness.  Yet I kept moving inch by inch, for there was now no stopping, and soon felt solid rock once more beneath my groping feet.  With prayer on lips I crouched, sick and dizzy, close in against the wall, watching Cairnes where he followed along the same perilous path.

CHAPTER XXXII

CHIEF PRIEST OF THE SUN

The rock shelf we followed became gradually somewhat wider, so I moved forward with greater freedom.  The path continued to ascend, winding unevenly along the precipitous face of the cliff, until we must have climbed nearly to the summit of the mighty bluff.  But the overhanging crest rendered it impossible for us to do more than guess the situation.  We were but ants clinging to a wall and unable to see more than a few yards ahead.  Finally we attained a point where the cliff bulged outward in a wide curve, not unlike the rounded bow of a ship, and were compelled to move with renewed caution along the narrowed shelf, which was seemingly unsupported.  Creeping fearfully forward on hands and knees around the sharp corner I found myself before the yawning entrance to a cavern.  I realized that here was the ending of our toilsome climb, for I could see nothing beyond, excepting a precipitous wall of stone.  If the path had continuation, it must pass through the cave.

“Yonder yawns a gloomy-looking hole, Master Benteen,” muttered the Puritan, lying at full length beside me, and staring ahead.  “Yet my eyes see no sign of life to alarm us.”