Spence forced himself to smile in answer to her anxious look. "Don't worry about it. I don't mind. I wasn't sleeping anyway. When ComCen said I had a call coming through, I assumed something terrible had happened to Dad or one of the boys… you know."

"Everyone's fine, Spence. I just wanted to talk to you-I hope I'm not interrupting one of your experiments…" "No, no; I'm not working tonight."

"Well, I feel so awkward. I mean, just think, you're a million miles out in space and here I am talking to you like you were across town or something."

"Wait 'til you get the bill. You won't think I was all that close then." He paused, studying her face on the screen. Though only two years older then he was, Kate had always been the wise, benevolent elder sister. He saw her now, a mother of two growing boys, looking more than ever like a matron. She bore little resemblance to the picture of her he carried around in his head.

"You look tired, Spence. Are you feeling all right?" she was saying.

"I'm fine. I've been working a little too hard, that's all."

"Dad said you'd had an accident."

"It was nothing. I bumped my head."

The conversation seemed to dry up at that point. Kate licked her lips. She was trying to bridge the gap of all those miles by staring very hard into the vidphone screen. Spence realized. it was not a separation of miles but of life that she was trying to cross. She was trying to imagine his life in that place. Clearly, it was beyond her.

"Why did you call, Kate?" he asked softly.

"Are you angry? Don't be angry, Spence. You'll think it's silly-"

"I won't think it's silly, and I'm not angry. Believe me. Now go ahead and tell me."

She appeared as if she were about to confess a scarlet sin. "Spence, Tuesday's Dad's birthday."

A pang of guilt arrowed through him. He did not feel guilty for forgetting his father's birthday; he had done that often over the years. He felt guilty because the event meant nothing to him. He did not care, and Kate's reminder made him face the fact that other sons did remember; they did care.

"I'm sorry," he said flatly. "I forgot."

"That's not why I called. Not to remind you. Well, yes it is, but not how you think. Dad says that you told him you're going on some research trip."

"I told him that, yes. I remember."

"Anyway, he's got it in his head that he's never going to see you again. You know how he gets sometimes. No amount of talking will convince him. He says he's sure something terrible is going to happen to you on that trip-he doesn't even know where you're going-and that he'll never see you again."

Spence could see his father sitting in his faded red chair mumbling and fretting over his son's imagined demise. It was one of the stock images of Spence's childhood and he hated it.

"What do you want me to do, Kate?" he asked, wishing that his mother was still alive. At least she had been able to soothe his father's irrational fears; she had been the cooling balm poured out upon the fevered brow of her husband.

She answered hesitantly. "It would be nice if you would call him and wish him happy birthday. That way he could see you and hear your voice. It might convince him that you're still okay, and that you're thinking about him."

"I'd love to do that, Kate, but I can't. I'll be on my way to Mars by then. I'm leaving tomorrow night and I won't be back for some time." He did not feel like rehearsing the details of his trip with her.

"Mars! Really, Spencer? That's fantastic. Wait until I tell the boys-they'll be so thrilled." Her enthusiasm died almost at once. "But what about Dad?"

"I'm sorry. He'll just have to understand."

"But isn't there something you could do, Spence? Anything?"

"I could record a call and have it sent then. I could also send a souvenir of the station-he might like that."

"Would you? It would make him so happy. I'm sure whatever you could send would be fine. It isn't the gift, it's the thought that counts,"

But it was Kate's thought-and that was the whole point. "I'll get something on the next shuttle."

"Just send it to me. We're having a little family party for him on Tuesday night. I'll take care of everything."

"Fine. You'll be notified about the call. I'll make sure they give you plenty of time to get to the base."

There was a strained pause. "Well, Spence, I'd better go. Take care of yourself, now. And call when you get back. I know two boys who will want to hear their Uncle Spence tell 'em all about it."

"I'll do that, Kate. Good-bye."

"Good-bye, Spence."

The screen went dark. He sat for a moment gazing into the flat gray square. Then he stood stiffly and left the booth, feeling very hollow and alone, as if every liquid gram of compassion had been wrung out of him in the pitiful effort of conversation with one of his family members.

He wandered back to his quarters, gray-faced and eyes burning from the exhaustion of his long day. He stopped briefly at the Visitor's Center to browse among various souvenirs and memorabilia offered as mementos of a trip to Gotham. He selected a small, cast aluminum replica of the space station which was mounted on a grayish stone-part of an asteroid or a moon rock-and designed undoubtedly to be used as a paperweight.

He paid for his purchase, rattling off his account number to a bored clerk who dutifully punched in the data.

"You want it wrapped?" she asked, stifling a yawn.

"No thanks, I'll eat it here," he said, and stuffed the object into a zippered pocket and shambled off to his night's rest.

… MAINTAINING THE RUSE OF "business as usual" proved harder than Spence imagined. For one thing, Tickler seemed especially interested in his plans for the next run of experiments set to begin that night.

"When shall I tell our assistant, Mr. Millen, to join us?"

"Oh, at the usual time. I see no reason to deviate from our norm. Do you?"

"No, sir. Not at all. I just thought that you might have plans which would necessitate rescheduling. In that case I should know about them, that's all."

It was all Spence could do to keep from smirking. "I realize I have been somewhat unpredictable, Tickler. But I'm turning over a new leaf." He turned toward his officious assistant and a lopsided grin stole over his face. "Starting tonight you'll notice a dramatic departure from my usual habits."

Tickler bent his head to one side and sucked in his breath as if he were about to press the matter further, but then thought better of it. That left him holding his breath with his mouth open.

"Was there something else?" asked Spence cheerily.

"Ahh-no." Tickler exhaled like a leaky balloon. "I am quite satisfied." But he stood there blinking his tiny beady eyes as if he expected to be asked to stay to tea and would be disappointed if he were not.

Spence guessed he was waiting for additional information regarding his plans. He decided to end the conversation. "Well, then, if there's nothing else, I suggest we both get busy. There is a lot to be done before tonight. You may wish to catch some sleep before we begin. it could be a long one."

"Of course. Tickler turned and scuttled away. Spence watched him take up his place at the far end of the lab opposite his own work station.

All he needs, thought Spence, is whiskers and a tail, and the rodent family would have a new patriarch. …

SPENCE HAD NO INTENTION of showing up for the evening's session. But as the shift came to an end he made a point of remarking to Tickler, "I'll expect you here promptly at the beginning of the third shift. I want to start at once."

To this Tickler replied, "Punctuality is my middle name, Dr. Reston. "

"Of course it is," said Spence. "I had always wondered."