"Now there's nothing to be done for a day or two," he said wearily, "and I'm beginning to understand why people sleep all they can, on Dara. It's one way not to feel hungry."

Maril said tensely;

"You're going back? After they took the ship from you?"

"The job's not finished," he explained. "Not even the famine's ended, and the famine's a second-order effect. If there were no such thing as a blueskin, there'd be no famine. Food could be traded for. We've got to do something to make sure there are no more famines."

She looked at him oddly.

"It would be desirable," she said with irony. "But you can't do it."

"Not today, no," he admitted. Then he said longingly, "I'm about to catch up on some sleep."

Maril rose and went into the other cabin. He settled down into the chair and fell instantly asleep.

For very many ship-hours, then, there was no action or activity or happening of any imaginable consequence in the Med Ship. Very, very far away, light-years distant and light years apart, four shiploads of grain hurtled toward the famine-stricken planet of blueskins. Each great ship had a single semi-skilled blueskin for pilot and crew. Thousands of millions of suns blazed with violence appropriate to their stellar types in a galaxy of which a very small proportion had been explored and colonized by humanity. The human race was now to be counted in quadrillions on scores of hundreds of inhabited worlds, but the tiny Med Ship seemed the least significant of all possible created things. It could travel between star-systems and even star-cl.u.s.ters, but it was not yet capable of crossing the continent of suns on which the human race arose. And between any two solar systems the journeying of the Med Ship consumed much time. Which would be maddening for someone with no work to do or no resources in himself, or herself.

On the second ship-day Calhoun labored painstakingly and somewhat distastefully at the little biological laboratory. Maril watched him in a sort of brooding silence. Murgatroyd slept much of the time, with his furry tail wrapped meticulously across his nose.

Toward the end of the day Calhoun finished his task. He had a matter of six or seven cubic centimeters of clear liquid as the conclusion of a long process of culturing, and examination by microscope, and again culturing plus final filtration. He looked at a clock and calculated time.

"Better wait until tomorrow," he observed, and put the bit of clear liquid in a temperature-controlled place of safe-keeping.

"What is it?" asked Maril. "What's it for?"

"It's part of a job I have on hand," said Calhoun. He considered. "How about some music?"

She looked astonished. But he set up an instrument and fed microtape into it and settled back to listen. Then there was music such as she had never heard before. Again it was a device to counteract isolation and monotonous between-planet voyages. To keep it from losing its effectiveness, Calhoun rationed himself on music, as on other things.

Calhoun deliberately went for weeks between uses of his recordings, so that music was an event to be looked forward to and cherished.

When he tapered off the stirring symphonies of Kun Gee with tranquilizing, soothing melodies from the Rim School of composers, Maril regarded him with a very peculiar gaze indeed.

"I think I understand now," she said slowly, "why you don't act like other people. Toward me, for example. The way you live gives you what other people have to try to get in crazy ways,--making their work feed their vanity, and justify pride, and make them feel significant. But you can put your whole mind on your work."

He thought it over.

"Med Ship routine is designed to keep one healthy in his mind," he admitted. "It works pretty well. It satisfies all my mental appet.i.tes.

But naturally there are instincts--"

[Ill.u.s.tration]

She waited. He did not finish.

"What do you do about instincts that work and music and such things can't satisfy?"

Calhoun grinned wrily;

"I'm stern with them. I have to be."

He stood up and plainly expected her to go into the other cabin for the night. She did.

It was after breakfast-time of the next ship-day when he got out the sample of clear liquid he'd worked so long to produce. "We'll see how it works," he observed. "Murgatroyd's handy in case of a slip-up. It's perfectly safe so long as he's aboard and there are only the two of us."

She watched as he injected half a cc under his own skin. Then she shivered a little.

"What will it do?"

"That remains to be seen." He paused a moment. "You and I," he said with some dryness, "make a perfect test for anything. If you catch something from me, it will be infective indeed!"

She gazed at him utterly without comprehension.

He took his own temperature. He brought out the folios which were his orders, covering each of the planets he should give a standard Medical Service inspection. Weald was there. Dara wasn't. But a Med Service man has much freedom of action, even when only keeping up the routine of normal Med Service. When catching up on badly neglected operations, he necessarily has much more. Calhoun went over the folios.

Two hours later he took his temperature again. He looked pleased. He made an entry in the ship's log. Two hours later yet he found himself drinking thirstily and looked more pleased still. He made another entry in the log and matter-of-factly drew a small quant.i.ty of blood from his own vein and called to Murgatroyd. Murgatroyd submitted amiably to the very trivial operation Calhoun carried out. Calhoun put away the equipment and saw Maril staring at him with a certain look of shock.

"It doesn't hurt him," Calhoun explained. "Right after he's born there's a tiny spot on his flank that has the pain-nerves desensitized.

Murgatroyd's all right. That's what he's for!"

"But he's--your friend!"

"He's my a.s.sistant. I don't ask anything of him that I can do myself.

But we're both Med Service. And I do things for him that he can't do for himself. For example, I make coffee for him."

Murgatroyd heard the familiar word. He said;

"_Chee!_"

"Very well," agreed Calhoun. "We'll all have some."

He made coffee. Murgatroyd sipped at the cup especially made for his little paws. Once he scratched at the place on his flank which had no pain-nerves. It itched. But he was perfectly content. Murgatroyd would always be contented when he was somewhere near Calhoun.

Another hour went by. Murgatroyd climbed up into Calhoun's lap and with a determined air went to sleep there. Calhoun disturbed him long enough to get an instrument out of his pocket. He listened to Murgatroyd's heartbeat with it while Murgatroyd dozed.

"Maril," he said. "Write down something for me. The time, and ninety-six, and one-twenty over ninety-four."

She obeyed, not comprehending. Half an hour later--still not stirring to disturb Murgatroyd--he had her write down another time and sequence of figures, only slightly different from the first. Half an hour later still, a third set. But then he put Murgatroyd down, well satisfied.

He took his own temperature. He nodded.

"Murgatroyd and I have one more ch.o.r.e to do," he told her. "Would you go in the other cabin for a moment?"

She went disturbedly into the other cabin. Calhoun drew a sample of blood from the insensitive area on Murgatroyd's flank. Murgatroyd submitted with complete confidence in the man. In ten minutes Calhoun had diluted the sample, added an anticoagulant, shaken it up thoroughly, and filtered it to clarity with all red and white corpuscles removed.

Another Med Ship man would have considered that Calhoun had had Murgatroyd prepare a splendid small sample of antibody-containing serum, in case something got out of hand. It would a.s.suredly take care of two patients.