Tes watched him go with a feeling of relief for which she was unable to account. As soon as he was out of sight, Thrykar picked up the gas cylinders and equipment case, made sure the latter was sealed watertight, and began once more to struggle down the hill with the load. He refused Tes’ assistance, so she, unburdened, saved herself the climb by slipping over the edge of the pit.
She was in the tiny galley preparing food by the time Thrykar came aboard; she brought him some within a few minutes and remained in the laboratory to watch what he was doing.
He had transferred the sample of blood to a small, narrow-necked flask, which was surrounded by a heating pad set for what the book claimed to be the human blood temperature. The liquid showed no sign of clotting; evidently some inhibiting chemical had been in the hypodermic when the specimen was obtained. Tes watched with interest as Thrykar bent over the flask and permitted a thin stream of his own blood, flowing from a valve in the great vein of his tongue, to mingle with that of the human being. The valve, and the tiny muscles controlling it, were a product of surgery; the biologists of Thrykar’s race had not yet succeeded in tampering with their genes sufficiently to produce such a mechanism in the course of normal development. The delicate operation was performed at the same time the individual received his first “refreshment,”
and was the most unpleasant part of the entire process. Tes, not yet of age, was not looking forward to the change with pleasure.
The flask filled, Thrykar straightened up. His wife looked at the container with interest. “Their blood doesn’t look any different from ours,” she remarked. “Why this mixing outside?”
“There are differences sufficient to detect either chemi-cally or by microscope. It is necessary, of course, that there be some difference; otherwise there would be no reaction on the part of my own blood. However, when the blood is from two different species, it is best to let the initial reaction take place outside the body. That would be superfluous if my donor was a member of our own race, with merely a differing blood type. If you weren’t the same as I, it would have saved us a lot of trouble.”
“Why is it that two people who have been treated, like you, are not particularly helpful to each other if they wish to use each other’s blood?”
“In an untreated blood stream, there are leucocytes — little, colorless, amoeboid cells which act as scavengers and defenders against invading organisms. The treatment destroys those, or rather, so modifies them that they cease to be independent entities — I speak loosely; of course they are never really independent — and form a single, giant cell whose ramifications extend throughout the body of the owner, and which is in some obscure fashion tied in with, or at least sensitive to, his nervous system. As you know, a treated individual can stop voluntarily the bleeding from a wound, overcome disease and the chemi-cal changes incident to advancing age — in fact, have a control over the bodily functions usually called ‘involun-tary’ to a degree which renders him immune to all the more common causes of organic death.” One of his tentacles reached out in a caress. “In a year or two you will be old enough for the treatment, and we need no longer fear —
separation.
“But to return to your question. The giant leucocyte, after a few months, tends to break up into the original, uncontrollable type; and about half the time, if that process is permitted to reach completion, the new cells no longer act even as inefficient defenders; they attack, instead, and the victim dies of leukemia. The addition to the blood stream of white cells from another type of blood usually halts the breakdown — it’s as though the great cell were intelligent, and realized it had to remain united to keep its place from being usurped; and in the few cases where this fails, at least the leukemia is always prevented.”
“I knew most of that,” replied Tes, “but not the leukemia danger. I suppose that slight risk is acceptable, in view of the added longevity. How long does that blood mixture of yours have to stand, before you can use it?”
“About four hours is best, I understand, though the precise time is not too important. I’ll take this shot before we go to bed, let it react in me overnight, and tomorrow we’ll catch another human being, get a full donation, and — then we can start enjoying our vaca-tion.”
Jackie Wade ran up the road, still hoping to catch up with his brother. He knew he had fallen asleep, but was sure it had been for only a moment; Jim couldn’t be more than five minutes ahead of him. He had not the slightest suspicion of what had happened during that brief doze; he had lost as much blood before, in the minor accidents that form a normal part of an active boy’s existence. His throat did itch slightly, but he was hardened to the activities of the mosquito family and its relatives, and his only reaction to the sensation was mild annoyance.
As he had hoped, he caught the others before they reached his home, though the margin was narrow enough. Jim looked back as he heard his brother’s running footsteps, and stopped to wait for him; the other boys waved farewell and went on. Jackie reached his brother’s side and dropped to a walk, panting.
“What took you so long?” asked Jim. “I bet you went swimming again!” He glared down at the younger boy.
“Honest, I didn’t,” gasped Jackie. “I was just comin’ on slowly — thinking.”
“When did you start thinking, squirt?” An exploratory hand brushed over his hair. “I guess you didn’t at that; it’s almost as dry as mine. We’d both better stay outside a while longer. Here, drop my books on the porch and find out what time it is.”
Jackie nodded, took the books as they turned in at the gate, and ran around to the small rear porch, where he dropped them. Looking in through the kitchen window, he ascertained that it was a few minutes after four; then he jumped down the steps and tore after his brother. Together, they managed to fill the hour and a half before supper with some of the work which they were supposed to have done earlier in the day; and by the time their mother rang the cow bell from the kitchen door, hair and undershirts were dry. The boys washed at the pump, and clattered indoors to eat. No embarrassing questions were asked at the meal, and the Wade offspring decided they were safe this time.
Undressing in their small room that night, Jackie said as much. “How often do you think we can get away with it, Jim? It’s so close to the road, I’m always thinking someone will hear us as they go by. Why don’t they like us to swim there, anyway? We can swim as well as anyone.”
“I suppose they figure if we did get drowned they’d have an awful time getting us out; they say it’s over a hundred feet deep,” responded the older boy, somewhat absently.
Jackie looked up sharply at his tone. Jim was carefully removing a sock and exposing a rather ugly scrape which obviously had been fresh when the sock was donned. Jackie came over to examine it. “How did you do that?” he asked.
“Hit my foot against the rock the first time I dived. It’s a little bit sore,” replied Jim.
“Hadn’t we better have Mother put iodine on it?”
“Then how do I explain where I got it, sap? Go get the iodine yourself and I’ll put it on; but don’t let them see you get it.”
Jackie nodded, and ran barefooted downstairs to the kitchen. He found the brown bottle without difficulty, brought it upstairs, watched Jim’s rather sketchy applica-tion of the antiseptic, and returned the bottle to its place. When he returned from the second trip Jim was in bed; so he blew out the lamp without speaking and crawled under his own blankets.