Perhaps here was an avenue to freedom.

On and on I went. The floor of the corridor was level and there were no forks nor cross corridors. It curved a little twice, but not much. I kept thinking, well, I must be nearly to the end of it; but on and on it went. The walls became damp, and the corridor stunk of mold; and then I came to a sharp declivity. For a moment I hesitated, but only for a moment. The floor inclined downward at an angle of some 15 degrees, and by the time I reached level going again I must have been thirty or forty feet below the original level. The walls and ceiling dripped moisture. The floor was slimy with it. I walked on and on along this black, interminable tunnel. I thought it would never end; and when it did, as it must, into what new predicament would I find that it had lured me? Sometimes I thought of turning back, but that was only because I thought of Janai and her dependence upon me.

"Hormad!" I could still hear her calling me that, and I could feel the contempt and loathing that she could not have entirely hidden had she tried. And the way she spoke of Vor Daj in the same breath, and the way her voice changed! Once again a wave of jealousy of myself swept over me; but my sense of humor came to my rescue, and I laughed. That laugh resounded in the corridor, sepulchral and eerie. I didn't laugh again- it was too horrible.

Now the floor of the corridor was rising again. Up and up until I felt that I must have gained the original level; and then, suddenly, I saw light ahead, or rather lesser darkness; and a moment later I stepped out into the open. It was night. Neither moon was in the sky. Where was I? I realized that I had travelled miles, perhaps, through that gloomy corridor. I must be outside the walls of Morbus, but where?

Suddenly a figure loomed before me, and in the dim light I saw that it was a hormad. "Who are you?" it demanded. "What are you doing here?" and without waiting for an answer it came for me with a longsword.

That was language I understood, and had an answer to. I drew and engaged the thing. It was a better swordsman than any I had previously engaged. It knew some tricks that I thought only the pupils of John Carter knew. When it discovered that I had the solution of all its tricks, it let out a yell; and in a moment or two three other figures came barging out of the night. The leader was no hormad, but a tall red man. He had scarcely engaged me before I recognized him.

"John Carter!" I cried. "It is I, Vor Daj."

Instantly he dropped his point and stepped back. "Vor Daj!" he exclaimed. "In the name of my first ancestor, how did you get here?"

Ras Thavas and a second hormad came up, and I told them briefly how I had discovered the 17th cell and the opening into the corridor.

"And now tell me," I said, "what you are doing here."

"Let Ras Thavas tell you," said The Warlord.

"Morbus is an ancient city," said the great surgeon. "It was built in prehistoric times by a people who are now extinct. In my flight after our defeat at Toonol I discovered it. I have remodeled and rebuilt it, but largely upon the foundations of the old city, which was splendidly built. There is much about it of which I know nothing. There were plans of many of the buildings, including those of the laboratory building. I noticed that circle in cell 17, just as you did. I thought it meant something, but never had the time or inclination to investigate. When we decided to hide your body where it could not be found and destroyed if anything went wrong, I selected cell 17, with the result that we discovered the tunnel to this island which lies fully two miles from Morbus.

"Dur-dan and Il-dur-en carried your body down to cell 17, and we brought them with us. They are two of my best hormads, intelligent and loyal. Having escaped from Morbus, we decided to attempt to make our way to the west end of the Great Toonolian Marsh, recover John Carter's flier, and fly to Helium in the hope that I might arrive in time to save Dejah Thoris from death.

"We have been occupied in building a boat for the long journey through the marsh, and it is about completed. We were in a quandary as to what to do about you. We did not want to desert you; but as the flier will accommodate but two men, you would have to be left somewhere until we could return; and you were safer in Morbus than you would have been in the hills beyond Phundahl."

"You shouldn't have given me a thought," I said. "Our sole objective was to find you and get you back to Helium as quickly as possible. I knew when we set out that I should have to be left behind when you were located, as the flier is not designed for more than two. That would have been a small sacrifice to have made for the Princess of Helium. The Warlord would have sent for me later."

"Naturally," said The Warlord. "Nevertheless, I hated to leave you here; but there was no alternative. We planned to send Il-dur-en back into the city with a message explaining everything to you. Dur-dan is to accompany us. If we manage to escape from the marsh and reach the flier, he will attempt to return to Morbus."

"When do you expect to start?" I asked.

"The boat will be finished tomorrow, and we shall set out as soon as it is dark. We plan to travel by night, resting and hiding during the daylight hours, as Ras Thavas, who is familiar with the marsh, assures me that it would be impossible for any but a large force of warriors to traverse the marsh by day. Many of the islands are inhabited by savage aborigines or by even more savage pirates and outlaws. The Great Toonolian Marshes are the last dregs of the great oceans that once covered a considerable portion of Barsoom, and the creatures which inhabit them are the last dregs of humanity."

"Is there any way in which I can be of help to you?" I asked.

"No," he said. "You have already sacrificed enough."

"Then I shall go back to the city before my absence is noticed. I have responsibilities there almost equal to your own, sir."

"What do you mean?" he asked.

"Janai," I said.

"What of her? Have you found her?"

I then told them of all that had transpired of which they knew nothing, that Ay-mad was jeddak and sole ruler of Morbus, that I was an odwar and in charge of the laboratory building, and that Janai had been given into my protection.

"So you are in charge of the laboratory building," said Ras Thavas. "How does it there in my absence?"

"Horribly," I said. "The only compensation for your absence is the fact that the production of hormads will have to cease, but we are faced now with something that may prove infinitely worse than hormads." Then I told him of what was transpiring in No. 4 vat room.

He appeared deeply concerned. "That is deplorable," he said. "It is something that I have always feared and sedulously guarded against. By all means make every preparation that you can to be prepared to escape from Morbus if you are unable to stem the growth in No. 4 vat room. Eventually it will envelop the entire island if it is not checked. Theoretically, it might cover the entire surface of Barsoom, smothering all other forms of life. It is the original life principle that cannot die, but it must be controlled. Nature controlled it, but I have learned to my sorrow that man cannot. I interfered with the systematic functioning of Nature; and this, perhaps, is to be my punishment."

"But how can I stem the growth? How can I stop this horror from spreading?" I demanded.

He shook his head. "There is but one thing, another phenomenon of Nature, that can check it."

"And that?" I asked.

"Fire," he said, "but evidently it has gone too far for that."

"I am afraid so," I said.

"About all that you can do now is to save yourself and Janai from it and wait for us to return."

"I shall come back with a sufficient force of men and ships to reduce Morbus and rescue you," said The Warlord.