"What!"

"There is Martian life, you know. When Earthmen first arrived, Mars was covered with simple forms of life. There were giant algae whose blue-green color was seen telescopically even before space-travel was invented. There were bacteria-like forms that lived on the algae and even little insect-like creatures that were free-moving, yet manufactured their own food like plants."

"Do they still exist?"

"Why, certainly. We clear them off the land completely before converting areas to our own farms and introduce our own strains of bacteria, the ones that are necessary to plant growth. Out in the uncultivated areas, however, Martian life still flourishes."

"But how can they be affecting our plants, then.''

"That's a good question. You see, Martian farms are not like the Earth farm lands you're used to. On Mars, the farms are not open to sun and air. The sun on Mars doesn't give enough heat for Earth plants and there is no rain. But there is good, fertile soil and there is quite enough carbon dioxide which the plants live on primarily. So crops on Mars are grown under vast sheets of glass. They are seeded, cared for, and harvested by nearly automatic machinery so that our farmboys are machinists more than anything else. The farms are artificially watered by a system of planet-wide piping that carries back to the polar icecaps.

"I tell you this so you will realize that it would be difficult to infect plants ordinarily. The fields are closed and guarded from all directions except from beneath."

"What does that mean?" asked David.

"It means that underneath are the famous Martian caverns and within them there may be intelligent Martians."

"You mean Martian men?"

"Not men. But organisms as intelligent as man. I have reason to believe that there are Martian intelligences that are probably anxious to drive us intruding Earthmen from the face of their planet!"

"What reason?" demanded David.

Benson looked embarrassed. He moved one hand slowly over his head, smoothing the sparse strands of light hair that did not manage to hide the pink streaks of hairless skull that lay between. He said, "None that I could convince the Council of Science with. None that I could even present to Mr. Makian. But I believe I'm right."

"Is it anything you would care to talk about?"

"Well, I don't know. Frankly, it's been a long time since I've spoken to anyone but farmboys. You're a college man obviously. What did you major in?"

"History," said David promptly. "My thesis concerned the international politics of the early atomic age."

"Oh." Benson looked disappointed. "Any courses in science at all?"

"I had a couple in chemistry; one in zoology."

"I see. It occurred to me that I might be able to convince Mr. Makian to let you help me in my laboratory. It wouldn't be much of a job, especially since you have no scientific training, but it would be better than what Hennes will have you doing."

"Thank you, Mr. Benson. But about the Martians?"

"Oh yes. It's simple enough. You may not know it but there are extensive caves under the Martian surface, perhaps several miles under. So much is known from earthquake data, or, rather, Marsquake data. Some investigators claim they are merely the result of natural water action in the days when Mars still had oceans, but then radiation has been picked up that has its source beneath the soil and which can't have a human source but must have some intelligent source. The signals are too orderly to be anything else.

"It makes sense, really, if you stop to think about it. In the youth of the planet there was sufficient water and oxygen to support life, but with a gravity only two fifths that of Earth, both substances leaked slowly away into space. If there were intelligent Martians, they must have been able to foresee that. They might have built huge caverns well underneath their soil, into which they could retire with enough water and air to continue indefinitely, if they kept their population stable. Now suppose these Martians found that their planet's surface was harboring intelligent life once more-life from another planet. Suppose they resented it or feared our eventual interference with them. What we call food poisoning might be bacteriological warfare."

David said thoughtfully, "Yes, I see your point."

"But would the Syndicate? Or the Council of Science? Well, never mind. I'll have you working for me soon, and perhaps we'll be able to convince them yet."

He smiled and held out a soft hand which was swallowed up in David Starr's large one.

"I think they'll be letting you out now," Benson said.

They did let him out, and for the first time David had the chance to observe the heart of a Martian farm. It was domed, of course, as the city had been. David had been sure of that from the instant he had regained consciousness. You couldn't expect to be breathing free air and living under Earth-strength gravity unless you were within a powered dome.

Naturally the dome was much smaller than that of a city. At its highest it was only about one hundred feet, its translucent structure visible in all its details, strings of white fluorescent lights outdoing the translucent glimmer of the sunlight. The whole structure covered about half a square mile.

After the first evening, however, David had little time to extend his observations. The farm dome seemed full of men and they all had to be fed three times a day. In the evenings particularly, with the day's work done, there seemed no end to them. Stolidly he would stand behind the chow table while farmboys with plastic platters moved past him. The platters, David found out eventually, were manufactured especially for Martian farm use. Under the heat of human hands they could be molded and closed about the food at such times as it was necessary to carry meals out to the desert. Molded so, they kept the sand out and the heat in. Within the farm dome they could be flattened out again and used in the usual way.

The farmboys paid David little attention. Only Bigman, whose lithe frame slipped among the tables replacing sauce bottles and spice containers, waved to him. It was a terrible drop in social position for the little fellow, but he was philosophical about it.

"It's only for a month," he had explained one time in the kitchen, when they were preparing the day's stew and the head cook had left on his own business for a few minutes, "and most of the fellows know the score and are making it easy for me. Of course there's Griswold, Zukis, and that bunch: the rats that try to get somewhere by licking Hennes's boots. But what in Space do I care? It's only a few weeks."

Another time he said, "Don't let it bother you about the boys not cottoning to you. They know you're an Earthman, see, and they don't know you're pretty good for an Earthman, like I do. Hennes is always poking about after me, or else Griswold is, to make sure I don't talk to them, or else they would have heard the facts from me. But they'll get wise."

But the process was taking time. For David, it remained the same: a farmboy and his platter; a dollop of mashed potatoes, a ladle of peas, and a small steak (animal food was much scarcer on Mars than plant food, since meat had to be imported from Earth). The farmboy then helped himself to a sliver of cake and a cup of coffee. Then another farmboy with another platter; another dollop of mashed potatoes, another ladle of peas, and so on. To them, it seemed, David Starr was just an Earthman with a ladle in one hand and a large-tined fork in the other. He wasn't even a face; just a ladle and a fork.

The cook stuck his head through the door, his little eyes peering piggily over the sagging pouches" beneath. '"Hey, Williams. Rattle your legs and get some food into the special mess."