“Well, Ganymede is a million kilometres from Jupiter. That means a round-trip delay of six seconds. No, you need a controller on the spot to handle emergencies in real time. Let me show you something. Mind if I use this?”

“Go ahead.”

Falcon picked up a postcard that was lying on Webster’s desk, they were almost obsolete on Earth, but this one showed a 3-D view of a Martian landscape, and was decorated with exotic and expensive stamps. He held it so that it dangled vertically.

“This is an old trick, but helps to make my point. Place your thumb and finger on either side, not quite touching. That’s right.”

Webster put out his hand, almost but not quite gripping the card.

“Now catch it.”

Falcon waited for a few seconds, then, without warning, he let go of the card. Webster’s thumb and finger closed on empty air.

“I’ll do it again, just to show there’s no deception. You see?”

Once again, the falling card had slipped through Webster’s fingers.

“Now you try it on me.

This time, Webster grasped the card and dropped it without warning. It had scarcely moved before Falcon had caught it. Webster almost imagined he could hear a click, so swift was the other’s reaction.

“When they put me together again,” Falcon remarked in an expressionless voice, “the surgeons made some improvements. This is one of them and there are others. I want to make the most of them. Jupiter is the place where I can do it.”

Webster stared for long seconds at the fallen card, absorbing the improbable colours of the Trivium Charontis Escarpment. Then he said quietly: “I understand. How long do you think it will take?”

“With your help, plus the Bureau, plus all the science foundations we can drag in, oh, three years. Then a year for trials we’ll have to send in at least two test models. So, with luck, five years.

“That’s about what I thought. I hope you get your luck, you’ve earned it. But there’s one thing I won’t do.”