“That’s right. That’s why we ask for volunteers. But we haven’t lost a man so far. Sometimes a volunteer will get pretty sick, but if a food passes all the other tests, you can usually depend on its not killing a human being.”
“I gather that this is a pretty unusual case, then?”
Pilar frowned. “As far as I know, yes. But if something kills all the test animals, we don’t ask for humans to try it out. We assume the worst and forget it.” He looked musingly at the wall. “I wonder how many edible plants we’ve by-passed that way?” he asked softly, half to himself.
“What are you going to do next?” the colonel asked. “My men are getting hungry.”
Smathers looked up from the report in alarm, and Pilar had a similar expression on his face.
“For Pete’s sake,” said Smathers, “don’t tell anyone—not anyone—about this, just yet. We don’t want all your men rushing out in the forest to gobble down those things until we are more sure of them. Give us a few more days at least.”
The colonel patted the air with a hand. “Don’t worry. I’ll wait until you give me the go-ahead. But I’ll want to know your plans.”
Pilar pursed his lips for a moment before he spoke. “We’ll check up on MacNeil for another forty-eight hours. We’d like to have him transferred over here, so that we can keep him in isolation. We’ll feed him more of the… uh… what’d he call ’em, Smathers?”
“Banana-pears.”
“We’ll feed him more banana-pears, and keep checking. If he is still in good shape, we’ll ask for volunteers.”
“Good enough,” said the colonel. “I’ll keep in touch.”
On the morning of the third day in isolation, MacNeil rose early, as usual, gulped down his normal assortment of vitamins, added a couple of aspirin tablets, and took a dose of Epsom salts for good measure. Then he yawned and leaned back to wait for breakfast. He was certainly getting enough fresh fruit, that was certain. He’d begun to worry about whether he was getting a balanced diet—he’d heard that a balanced diet was very important—but he figured that the doctors knew what they were doing. Leave it up to them.
He’d been probed and needled and tested plenty in the last couple of days, but he didn’t mind it. It gave him a feeling of confidence to know that the doctors were taking care of him. Maybe he ought to tell them about his various troubles; they all seemed like nice guys. On the other hand, it wouldn’t do to get booted out of the Service. He’d think it over for a while.
He settled back to doze a little while he waited for his breakfast to be served. Sure was nice to be taken care of.
Later on that same day, Dr. Pilar put out a call for volunteers. He still said nothing about MacNeil; he simply asked the colonel to say that it had been eaten successfully by a test animal.
The volunteers ate their banana-pears for lunch, approaching them warily at first, but soon polishing them off with gusto, proclaiming them to have a fine taste.
The next morning, they felt weak and listless.
Thirty-six hours later, they were dead.
“Oxygen starvation,” said Smathers angrily, when he had completed the autopsies.
Broderick MacNeil munched pleasantly on a banana-pear that evening, happily unaware that three of his buddies had died of eating that self-same fruit.
The chemist, Dr. Petrelli, looked at the fruit in his hand, snarled suddenly, and smashed it to the floor. Its skin burst, splattering pulp all over the gray plastic.
“It looks,” he said in a high, savage voice, “as if that hulking idiot will be the only one left alive when the ship returns!” He turned to look at Smathers, who was peering through a binocular microscope. “Smathers, what makes him different?”
“How do I know?” growled Dr. Smathers, still peering. “There’s something different about him, that’s all.”
Petrelli forcibly restrained his temper. “Very funny,” he snapped.
“Not funny at all,” Smathers snapped back. “No two human beings are identical—you know that.” He lifted his gaze from the eyepiece of the instrument and settled in on the chemist. “He’s got AB blood type, for one thing, which none of the volunteers had. Is that what makes him immune to whatever poison is in those things? I don’t know.
“Were the other three allergic to some protein substance in the fruit, while MacNeil isn’t? I don’t know.
“Do his digestive processes destroy the poison? I don’t know.
“It’s got something to do with his blood, I think, but I can’t even be sure of that. The leucocytes are a little high, the red cell count is a little low, the hemoglobin shows a little high on the colorimeter, but none of ’em seems enough to do any harm.
“It might be an enzyme that destroys the ability of the cells to utilize oxygen. It might be anything!”
His eyes narrowed then, as he looked at the chemist. “After all, why haven’t you isolated the stuff from the fruit?”
“There’s no clue as to what to look for,” said Petrelli, somewhat less bitingly. “The poison might be present in microscopic amounts. Do you know how much botulin toxin it takes to kill a man? A fraction of a milligram!”
Smathers looked as though he were about to quote the minimum dosage, so Petrelli charged on: “If you think anyone could isolate an unknown organic compound out of a—”
“Gentlemen! Please!” said Dr. Pilar sharply. “I realize that this is a strain, but bickering won’t help. What about your latest tests on MacNeil, Dr. Smathers?”
“As far as I can tell, he’s in fine health. And I can’t understand why,” said the physician in a restrained voice.
Pilar tapped one of the report sheets. “You mean the vitamins?”
“I mean the vitamins,” said Smathers. “According to Dr. Petrelli, the fruits contain neither A nor B1. After living solely on them for four weeks now, he should be beginning to show some deficiencies—but he’s not.
“No signs?” queried Dr. Pilar. “No symptoms?”
“No signs—at least no abnormal ones. He’s not getting enough protein, but, then, none of us is.” He made a bitter face. “But he has plenty of symptoms.”
Dr. Petrelli raised a thin eyebrow. “What’s the difference between a sign and a symptom?”
“A sign,” said Smathers testily, “is something that can be objectively checked by another person than the patient. Lesions, swellings, inflammations, erratic heartbeat, and so on. A symptom is a subjective feeling of the patient, like aches, pains, nausea, dizziness, or spots before the eyes.
“And MacNeil is beginning to get all kinds of symptoms. Trouble is, he’s got a record of hypochondria, and I can’t tell which of the symptoms are psychosomatic and which, if any, might be caused by the fruit.”
“The trouble is,” said Petrelli, “that we have an unidentifiable disease caused by an unidentifiable agent which is checked by an unidentifiable something in MacNeil. And we have neither the time nor the equipment to find out. This is a job that a fully equipped research lab might take a couple of years to solve.”
“We can keep trying,” said Pilar, “and hope we stumble across it by accident.”
Petrelli nodded and picked up the beaker he’d been heating over an electric plate. He added a chelating agent which, if there were any nickel present, would sequester the nickel ions and bring them out of solution as a brick- red precipitate.
Smathers scowled and bent over his microscope to count more leucocytes.
Pilar pushed his notes aside and went over to check his agar plates in the constant-temperature box.
The technicians who had been listening to the conversation with ears wide open went back to their various duties.
And all of them tried in vain to fight down the hunger pangs that were corroding at their insides.
Broderick MacNeil lay in his bed and felt pleasantly ill. He treasured each one of his various symptoms; each pain and ache was just right. He hadn’t been so comfortable in years. It really felt fine to have all those doctors
