But not for an instant did we hesitate; we flew rather than ran.  I felt within me the strength and resolve of ten men, and I knew then that there was something I must do and would do before I died, though a thousand devils stood in my way.

I do not know what led us; whether a remorseful Providence, who suddenly decided that we had been played with long enough, or the mere animal instinct of direction, or blind luck.  But so fast did we go that it seemed to me we had left the great cavern scarcely a minute behind us when I suddenly saw the steps of a steep stairway leading down from an opening on our right.

How my heart leaped then!  Harry uttered a hoarse cry of exultation.  The next instant we were dashing headlong down the steps, avoiding a fall by I know not what miracle.  And there before us was the entrance to the tunnel.

I held Harry back, almost shouting:  “You stay here; guard the entrance.  I’ll get her.”

“No,” he cried, pushing forward.  “I can’t stay.”

“Fool!” I cried, dashing him back.  “We would be caught like rats in a trap.  Defend that entrance—­with your life!”

I saw him hesitate, and, knowing that he would obey, I dashed forward into the tunnel.  When nearly to its end I made a misstep on the uneven ground and precipitated myself against the wall.  A sharp pain shot through my left shoulder, but at the time I was scarcely conscious of it as I picked myself up and leaped forward.  The end was in sight.

Just as I reached the foot of the spiral stairway I saw a black form descending from it.  That Inca never knew what hit him.  I did not use my spear; time was too precious.  He disappeared in the whirlpool beneath the base of the column through which Harry and I had once miraculously escaped.

But despair filled my heart as, with my feet on the first step of the spiral stairway, I cast a quick glance upward.  The upper half of the inside of the column was a raging furnace of fire.  How or from what it came I did not stop to inquire; I bounded up the stairway in desperate fury.

I did not know then that the stone steps were baking and blistering my feet; I did not know, as I came level with the base of the flames, that every hair was being singed from my head and body—­I only knew that I must reach the top of the column.

Then I saw the source of the flames as I reached them.  Huge vats of oil—­six, a dozen, twenty—­I know not how many—­were ranged in a circle on a ledge of stone encircling the column, and from their tops the fire leaped upward to a great height.  I saw what must be done; how I did it God only knows; I shut my eyes now as I remember it.

Hooking the rim of the vat nearest me with the point of my spear, I sent it tumbling down the length of the column into the whirlpool, many feet below.  Then another, and another, and another, until the ledge was empty.

Some of the burning oil, flying from the overturned vats, alighted on the stairway, casting weird patches of light up and down the whole length of the column.  Some of it landed on my body, my face, my hands.  It was a very hell of heat; my lungs, all the inside of me, was on fire.