"Where are we?" she asked.

Harry explained while we beached the raft. Then we broke out our provisions and partook of them.

"But why do we stop?" asked Desiree.

The words "Because we are not getting anywhere" rose to my lips, but I kept them back.

"For a rest and some air," I answered.

Desiree exclaimed: "But I want to go on!"

So as soon as we had eaten our fill we loaded the stuff again and prepared to shove off. By that time I think Harry, too, had realized the hopelessness of our expedition, for he had lost all his enthusiasm; but he said nothing, nor did I. We secured Desiree on her pile of skins and again pushed out into the current.

The cavern was not large, for we had been under way but a few minutes when its wall loomed up ahead and the stream again entered a tunnel, so low and narrow that I hesitated about entering at all. I consulted Harry.

"Take a chance," he advised. "Why not? As well that as anything."

We slipped through the entrance.

The current was extremely sluggish, and we barely seemed to move.

Still we went forward.

"If we only had a little speed we could stand it," Harry grumbled.

Which shows that a man does not always appreciate a blessing. It was not long before we were offering up thanks that our speed had been so slight.

To be exact, about an hour, as well as I could measure time, which pa.s.sed slowly; for not only were the minutes tedious, but the foulness of the air made them also extremely uncomfortable. Desiree was again lying down, half-unconscious but not asleep, for now and then she spoke drowsily. Harry complained of a dizziness in the head, and my own seemed ready to burst through my temples. The soroche of the mountains was agreeable compared to that.

Suddenly the swiftness of the current increased appreciably on the instant; there was a swift jerk as we were carried forward. I rose to my knees--the tunnel was too low to permit of standing--and gazed intently ahead. I could see nothing save that the stream had narrowed to half its former width, and was still becoming narrower.

We went faster and faster, and the stream narrowed until the bank was but a few feet away on either side.

"Watch the stern!" I called to Harry. "Keep her off with your spear!"

Then a wall loomed up directly ahead. I thought it meant another bend in the stream, and I strained my eyes intently in the effort to discover its direction, but I could see nothing save the black wall.

We approached closer; I shouted to Harry and Desiree to brace themselves for a shock, praying that the raft would meet the rock squarely and not on a corner.

I had barely had time to set myself and grasp the straps behind when we struck with terrific force. The raft rebounded several feet, trembling and shaking violently. The water was rushing past us with noisy impetuosity.

There was a cry from Desiree, and from Harry, "All right!" I crawled to the bow. Along the top the hide covering had been split open for several feet, but the water did not quite reach the opening.

And we had reached the end of our ambitious journey. For that black wall marked the finish of the tunnel; the stream entered it through a narrow hole, which accounted for the sudden, swift rush of the current.

Above the upper rim of the hole the surface of the water whirled about in a widening circle; to this had we been led by the stream that was to have carried us to the land of sunshine.

When I told Desiree she stared at me in silence! I had not realized before the strength of her hope. Speechless with disappointment, she merely sat and stared straight ahead at the black, unyielding rock.

Harry knelt beside her with his arm across her shoulders.

I roused him with a jerk of the arm.

"Come--get busy! A few hours in this hole and we'd suffocate. Do you realize that we've got to pull this raft back against the current?"

First it was necessary to repair the rent in the hide covering. This we did with strips of hide; and barely in time, for it was becoming wider every minute, and the water was beginning to creep in over the edge. But we soon had the ends sewed firmly together and turned our hands to the main task.

It appeared to be not only difficult, but actually impossible to force the raft back up-stream against the swift current. We were jammed against the rock with all the force of many tons of water. The oar was useless.

Getting a purchase on the wall with our hands, we shoved the raft to one side; but as soon as we got to the wall on the left the whirling stream turned us around again, and we found ourselves back in our original position, only with a different side of the raft against the rock. That happened three times.

Then we tried working to the right instead of the left, but with no better success. The force of the current, coming with all its speed against the unwieldy raft, was irresistible. Time and again we shoved round and started upstream, after incredible labor, only to be dashed back again against the rock.

We tried our spears, but their shafts were so slender that they were useless. We took the oar and, placing its end against the wall, shoved with all our strength. The oar snapped in two and we fell forward against the wall. We tore off some of the strips of hide from the raft and tried to fasten them to the wall on either side, but there was no protuberance that would hold them. Nothing remained to be done.

Harry and I held a consultation then and agreed on the only possible means of escape. I turned to Desiree:

"Can you swim?"

"Parfaitement," she replied. "But against that"--pointing to the whirling water--"I do not know. I can try."

I, who remember the black fury of that stream as it swept past us, can appreciate the courage of her.

We lost no time, for the foulness of the air was weakening us with every breath we took. Our preparations were few.

The two spears and about half of the provisions we strapped to our backs--an inconsiderable load which would hamper us but little. We discarded all our clothing, which was very little. I took the heavy skin which Desiree had worn and began to strap it also on top of my bundle, but she refused to allow it.

"I will not permit you to be handicapped with my modesty," she observed.

Then, with Desiree between us, we stepped to the edge of the raft and dived off together.

Driven as we were by necessity, we would have hesitated longer if we had known the full force of the undercurrent that seized us from beneath. Desiree would have disappeared without a struggle if it had not been for the support which Harry and I rendered her on either side.

But we kept on top--most of the time--and fought our way forward by inches. The black walls frowning at us from either side appeared to me to remain exactly the same, stationary, after a long and desperate struggle; but when I gave a quick glance behind I saw that we had pulled so far away from the raft that it was no longer in sight. That gave me renewed strength, and, shouting a.s.surance to Harry and Desiree, I redoubled my efforts. Desiree was by now almost able to hold her own, but we still supported her.

Every stroke made the next one easier, carrying us away from the whirlpool, and soon we swam smoothly. Less and less strong became the resistance of the current, until finally it was possible to float easily on our backs and rest.

"How far is it to the cavern?" Harry panted.

"Somewhere between one and ten miles," was my answer. "How the deuce should I know? But we'll make it now, I think. Can you hold out, Desiree?"

"Easily," she answered. "If only I could get some air! Just one good, long breath."

There was the danger, and on that account no time was to be lost.

Again we struck out into the blackness ahead. I felt myself no longer fresh, and began to doubt seriously if we should reach our goal.

But we reached it. No need to recount our struggles, which toward the end were inspired by suffering amounting to agony as we choked and gasped for sufficient air to keep us up.

Another hundred yards would have been too much for us; but it is enough that finally we staggered onto the bank at the entrance to the cavern in which we had previously rested, panting, dizzy, and completely exhausted.

But an hour in the cavern, with its supply of air, revived us; and then we sat up and asked ourselves: "What for?"

"And all that brings us--to this," said Harry, with a sweeping gesture round the cavern.