Turning to Desiree, I called to her to move behind a projecting bit of rock.  Then, leaving Harry to guard the crevice in case of a double attack, I took three of our four spears—­one of which had made the wound in my leg—­and stood at the water’s edge awaiting the approach of the rafts.

They came slowly, and their appearance was certainly anything but terrifying.

“Not much of a navy,” I called to Harry; and he answered, with a laugh:  “Lucky for us!  Look at our coast defense!”

One of the rafts was considerably ahead of the other, and in another minute it had approached within fifty feet of the ledge.  The Inca in the center stood with legs spread apart and his spear poised above his head; I made no movement, thinking that on such precarious footing he would have difficulty to hurl the thing at all.  Wherein I underrated his skill, and it nearly cost me dear.

Suddenly, with hardly a movement of his body, his arm snapped forward.  I ducked to one side instinctively and heard the spear whistle past my ear with the speed of a bullet, so close that the butt of the shaft struck the side of my head a glancing blow and toppled me over.

I sprang quickly to my feet, and barely in time, for I saw the Inca stoop over, pick up another spear from the raft, and draw it back above his head.  At the same moment the second raft drew up alongside, and as I fell to the ground flat on my face I heard the two spears whistle shrewdly over me.

At that game they were my masters; it would have been folly to have tried conclusions with them with their own weapons.  As the spears clattered on the ground thirty feet away I sprang to my feet and ran to the farther side of the ledge, where I had before noticed some loose stones in a corner.

With two or three of these in my hands I ran back to the water’s edge, meeting two more of the spears that came twisting at me through the air, one of which tore the skin from my left shoulder.

A quick glance at the crevice as I passed showed me Harry fighting at its entrance; they were at us there, too.  I heard Desiree shout something at me, but didn’t catch the words.

My first stone found its goal.  The two rafts, side by side not forty feet away, were a fair mark.  The stone was nearly the size of a man’s head and very heavy; I had all I could do to get the distance.

It struck the raft on the right fairly; the thing turned turtle in a flash, precipitating its occupants onto the other raft.  The added weight carried that, too, under the surface, and the six Incas were floundering about in the water.

I expected to see them turn and swim for the landing opposite; but, instead, they headed directly toward me!

The light from the urns was but faint, and it was not easy to distinguish their black heads against the black water; still, I could see their approach.  Two of them held spears in their hands; I saw the copper heads flash on high.