Dr. Stone said one night at dinner, "Roger, tomorrow is rent day. Shall I pay it for a full month? Mr. d'Avril says that the Burkhardts are talking about staying on."

"Pay it for six days only," Hazel advised. "We can do better than this after Venus departure - I hope."

Roger Stone looked up and scowled. "Look here, why pay the rent at all?"

"What are you saying, dear?"

"Edith, I've been chewing this over in my mind. When we first came here our plans, such as they were, called for living here through one wait." He referred to the fifteen months elapsed time from arrival Mars to Earth departure from Mars, using the economical orbits. Then we planned to shape orbit home. Fair enough, if this overrated tourist trap had decent housing. But I haven't been able to start writing my book. When Buster isn't climbing into my lap, his pet is slithering down the back of my neck."

"What do you suggest, dear?"

"Go to Phobos tomorrow, get the old Rock ready to go, and blast for Venus when the others do."

"Loud cheers!" agreed Meade. "Let's go!"

Dr. Stone said, "Meade, I thought you didn't like Venus?"

"I don't. But I don't like it here and I'm tired all the time. I'd like to get back into free fall."

"You shouldn't be tired. Perhaps I had better check you over."

"Oh, Mother, I'm perfectly well! I don't want to be poked at." Lowell grinned. "I know why she wants to go to Venus - Mr. Magill."

"Don't be a snoop, Snoop!" Meade went on with quiet dig­nity. "In case anyone is interested, I am not interested in Second Officer Magill - and I wouldn't be going in the Caravan in any case. Besides, I found out he afready has a wife in Colorado." Hazel said, "Well, that's legal. He's still eligible off Earth,"

"Perhaps it is, but I don't like it."

"Neither do I," Roger Stone cut in. "Meade, you weren't really getting interested in this wolf in sheep's clothing, were you?"

"Of course not, Daddy!" She added, "But I suppose I'll get married one of these days."

"That's the trouble with girls," Castor commented. "Give them education - boom! They get married. Wasted."

Hazel glared at them, "Oh, so? Where would you be if I hadn't married?"

"It didn't happen that way," Roger Stone cut in, "so there is no use talking about other possibilities. They probably aren't really possibilities at all, if only we understood it"

Pollux: "Predestination."

Castor: "Very shaky theory."

Roger grinned. "I'm not a determinist and you can't get my goat. I believe in free will."

Pollux: "Another very shaky theory."

"Make up your minds," their father told them. "You can't have it both ways."

"Why not?" asked Hazel. "Free will is a golden thread run­ning through the frozen matrix of fixed events."

"Not mathematical," objected Pollux.

Castor nodded. "Just poetry."

"And not very good poetry."

"Shut up!" ordered their father. "Boys, it's quite evident that you have gone to considerable trouble to change the subject. Why?"

The twins swapped glances; Castor got the go-ahead. "Uh, Dad, the way we see it, this Venus proposition hasn't been thought out"

"Go on. I suppose you have an alternative suggestion?"

"Well, yes. But we didn't mean to bring it up until after Venus departure."

"I begin to whiff something. What you mean is that you intended to wait until the planetary aspects were wrong - too late to shape orbit for Venus."

"Well, there was no use in letting the matter get cluttered up with a side issue."

"What matter? Speak up."

Castor said worriedly, "Look, Dad, we aren't unreasonable. We can compromise. How about this: you and Mother and Buster and Meade go to Venus in the War God. Captain Van would love to have you do it - you know that. And -"

"Slow up. And what would you be doing? And Hazel? Mother, are you in on this?"

"Not that I know of. But I'm getting interested."

"Castor, what's on your mind? Speak up."

Well, I will if you'll just let me, sir. You and the rest of the family could have a pleasant trip back home - in a luxury liner. Hazel and Pol and I - well, I suppose you know that Mars will be in a favorable position for the Hallelujah Node in about six weeks?"

"For a cometary-type orbit, that is," Pollux added.

"So it's the Asteroids again," their father said slowly. "We settled that about a year ago."

"But we're a year older now."

"More experienced."

"You're still not old enough for unlimited licenses. I suppose that is why you included your grandmother."

"Oh,no! Hazel is an asset."

"Thank you, boys."

"Hazel, you had no inkling of this latest wild scheme?"

"No. But I don't think it's so wild. I'm caught up and then some on my episodes - and I'm tired of this place. I've seen the Martian ruins; they're in a poor state of repair. I've seen a canal; it has water in it. I understand that the rest of the planet is much the same, right through to chapter eighty-eight. And I've seen Venus. I've never seen the Asteroids."

"Right!" agreed Castor. "We don't like Mars. The place is one big clip joint"

"Sharp operators," added Pollux.

"Sharper than you are, you mean," said Hazel.

"Never mind, Mother. Boys, it is out of the question. I brought my ship out from Luna; I intend to take her back." He stood up. "You can give Mr. d'Avril notice, dear."

"Dad!"

"Yes, Castor?"

"That was just a compromise offer. What we really hoped you would do - what we wanted you to do - was for all of us to go out to the Hallelujah."

"Eh? Why, that's silly! I'm no meteor miner."

"You could learn to be. Or you could just go for the ride. And make a profit on it, too."

"Yes? How?"

Castor wet his lips. "The sand rats are offering fabulous prices just for cold-sleep space. We could carry about twenty of them at least And we could put them down on Ceres on the way, let them outfit there'.

"Cas! I suppose you are aware that only seven out of ten cold-sleep passengers arrive alive in a long orbit?"

"Well... they know that That's the risk they are taking." Roger Stone shook his head. "We aren't going, so I won't have to find out if you are as cold-blooded as you sound. Have you ever seen a burial in space?"

"No, sir'."

"I have. Let's hear no more about cold-sleep freight."

Castor passed it to Pollux, who took over: "Dad, if you won't listen to us all going, do you have any objections to Cas and me going?"

"Eh? How 'do you mean?"

"As Asteroid miners, of course. We're not afraid of cold-sleep. If we haven't got a ship, that's how we would have to go."

"Bravo!" said Hazel. "I'm going with you, boys,"

"Please, Mother!" He turned to his wife. "Edith, I sometimes wonder if we brought the right twins back from the hospital."

"They may not be yours," said Hazel, "but they are my grandsons, I'm sure of that. Hallelujah, here I come! Anybody coming with me?"

Dr. Stone said quietly, "You know, dear, I don't much care for Venus, either. And it would give you leisure for your book"

The Rolling Stone shaped orbit from Phobos outward bound for the Asteroids six weeks later. This was no easy lift like the one from Luna to Mars; in choosing to take a 'cometary' or fast orbit to the Hallelujah the Stones had perforce to accept an expensive change-of-motion of twelve and a half miles per second for the departure maneuver. A fast orbit differs from a maximum-economy orbit in that it cuts the orbit being aban­doned at an angle instead of being smoothly tangent to it... much more expensive in reaction mass. The far end of the cometary orbit would be tangent to the orbit of the Hallelujah; matching at that point would be about the same for either orbit; it was the departure from Phobos-circum-Mars that would be rugged.