Directly beneath lay an irregular patch of rocky land elevated perhaps a dozen feet or more above the general level of the immediately surrounding country. Its extent was, at a rough guess, a hundred acres. Upon this stood the buildings and grounds, which were enclosed in a high wall. The tower upon which we stood was situated at about the centre of the total area enclosed. Beyond the outer wall was a strip of rocky ground on which grew a sparse forest of fair sized trees interspersed with patches of a jungle growth, and beyond all, what appeared to be an oozy marsh through which were narrow water courses connecting occasional open water-little lakes, the largest of which could have comprised scarce two acres. This landscape extended as far as the eye could reach, broken by occasional islands similar to that upon which we were and at a short distance by the skyline of a large city, whose towers and domes and minarets glistened and sparkled in the sun as though plated with shining metals and picked out with precious gems.

This, I knew, must be Toonol and all about us the Great Toonolian Marshes which extend nearly eighteen hundred Earth miles east and west and in some places have a width of three hundred miles. Little is known about them in other portions of Barsoom as they are frequented by fierce beasts, afford no landing places for fliers and are commanded by Phundahl at their western end and Toonol at the east, inhospitable kingdoms that invite no intercourse with the outside world and maintain their independence alone by their inaccessibility and savage aloofness.

As my eyes returned to the island at our feet I saw a huge form emerge from one of the nearby patches of jungle a short distance beyond the outer wall. It was followed by a second and a third. Ras Thavas saw that the creatures had attracted my notice.

"There," he said, pointing to them, "are three of a number of similar reasons why it would not have been safe for us to venture outside the enclosure."

They were great white apes of Barsoom, creatures so savage that even that fierce Barsoomian lion, the banth, hesitates to cross their path.

"They serve two purposes," explained Ras Thavas. "They discourage those who might otherwise creep upon me by night from the city of Toonol, where I am not without many good enemies, and they prevent desertion upon the part of my slaves and assistants."

"But how do your clients reach you?" I asked. "How are your supplies brought in?"

He tuned and pointed down toward the highest portion of the irregular roof of the building below us. Built upon it was a large, shed-like structure. "There," he said, "I keep three small ships. One of them goes every day to Toonol."

I was overcome with eagerness to know more about these ships, in which I thought I saw a much needed means of escape from the island; but I dared not question him for fear of arousing his suspicions.

As we turned to descend the tower runway I expressed interest in the structure which gave evidence of being far older than any of the surrounding buildings.

"This tower," said Ras Thavas, "was built some twenty-three thousand years ago by an ancestor of mine who was driven from Toonol by the reigning Jeddak of the time. Here, and upon other islands, he gathered a considerable following, dominated the surrounding marshes and defended himself successfully for hundreds of years. While my family has been permitted to return to Toonol since, this has been their home; to which, one by one, have been added the various buildings which you see about the tower, each floor of which connects with the adjacent building from the roof to the lowest pits beneath the ground."

This information also interested me greatly since I thought that I saw where it too might have considerable bearing upon my plan of escape, and so, as we descended the runway, I encouraged Ras Thavas to discourse upon the construction of the tower, its relation to the other buildings and especially its accessibility from the pits. We walked again in the outer garden and by the time we returned to Ras Thavas' quarters it was almost dark and the master surgeon was considerably fatigued.

"I feel that I shall sleep well to-night," he said as I left him.

"I hope so, Ras Thavas," I replied.

It was usually about three hours after the evening meal, which was served immediately after dark, that the establishment quieted down definitely for the night. While I should have preferred waiting longer before undertaking that which I had in mind, I could not safely do so, since there was much to be accomplished before dawn. So it was that with the first indications that the occupants of the building in which my work was to be performed had retired for the night, I left my quarters and went directly to the laboratory, where, fortunately for my plans, the bodies of Gor Hajus, the assassin of Toonol, and 378-J-493811-P both reposed. It was the work of a few minutes to carry them to adjoining tables, where I quickly strapped them securely against the possibility that one or both of them might not be willing to agree to the proposition I was about to make them, and thus force me to anaesthetize them again. At last the incisions were made, the tubes attached and the motors started. 378-J-493811-P, whom I shall hereafter call by his own name, Dar Tarus, was the first to open his eyes; but he had not regained full consciousness when Gor Hajus showed signs of life.

I waited until both appeared quite restored. Dar Tarus was eyeing me with growing recognition that brought a most venomous expression of hatred to his countenance. Gor Hajus was frankly puzzled. The last he remembered was the scene in the death chamber at the instant that his executioner had run a sword through his heart. It was I who broke the silence.

"In the first place" I said, "let me tell you where you are, if you do not already know."

"I know well enough where I am," growled Dar Tarus.

"Ah!" exclaimed Gor Hajus, whose eyes had been roaming about the chamber. "I can guess where I am. What Toonolian has not heard of Ras Thavas? So they sold my corpse to the old butcher did they? And what now? Did I just arrive?"

"You have been here six years," I told him, "and you may stay here for ever unless we three can reach an agreement within the next few minutes, and that goes for you too, Dar Tarus."

"Six years!" mused Gor Hajus. "Well, out with it, man. What do you want? If it is to slay Ras Thavas, no! He has saved me from utter destruction; but name me some other, preferably Vobis Kan, Jeddak of Toonol. Find me a blade and I will slay a hundred to regain life."

"I seek the life of none unless he stands in the way of the fulfilment of my desire in this matter that I have in hand. Listen! Ras Thavas had here a beautiful Duhorian girl. He sold her body to Xaxa, Jeddara of Phundahl, transplanting the girl's brain to the wrinkled and hideous body of the Jeddara. It is my intention to regain the body, restore it to its own brain and return the girl to Duhor."

Gor Hajus grinned. "You have a large contract on your hands," he said, "but I can see that you are a man after my own heart and I am with you. It will give freedom and fighting, and all that I ask is a chance for one thrust at Vobis Kan."

"I promise you life," I replied; "but with the understanding that you serve me faithfully and none other, undertaking no business of your own, until mine has been carried to a successful conclusion."

"That means that I shall have to serve you for life," he replied, "for the thing you have undertaken you can never accomplish; but that is better than lying here on a cold ersite slab waiting for old Ras Thavas to come along and carve out my gizzard. I am yours! Let me up, that I may feel a good pair of legs under me again."