Seldon panted, facing a tree, holding it closely, embracing it. He watched for the flying object to make its appearance again so that he could back about the tree and hide on the far side, like a squirrel.

The tree was cold, its bark was rough, it gave no comfort—but it offered cover. Of course, that might be insufficient, if he was being searched for with a heat-seeker, but, on the other hand, the cold trunk of a tree might blur even that.

Below him was hard-packed soil. Even in this moment of hiding, of attempting to see his pursuer while remaining unseen, he could not help wondering how thick the soil might be, how long it had taken to accumulate, how many domes in the warmer areas of Trantor carried forests on their back, and whether the trees were always confined to the creases between domes, leaving the higher regions to moss, grass, and underbrush.

He saw it again. It was not a hypership, nor even an ordinary air-jet. It was a jet-down. He could see the faint glow of the ion trails coming out at the vertices of a hexagon, neutralizing the gravitational pull and allowing the wings to keep it aloft like a large soaring bird. It was a vehicle that could hover and explore a planetary terrain.

It was only the clouds that had saved him. Even if they were using heat-seekers, that would only indicate there were people below. The jet-down would have to make a tentative dive below the banked ceiling before it could hope to know how many human beings there were and whether any of them might be the particular person the parties aboard were seeking.

The jet-down was closer now, but it couldn’t hide from him either. The rumble of the engine gave it away and they couldn’t turn that off, not as long as they wished to continue their search. Seldon knew the jet-downs, for on Helicon or on any undomed world with skies that cleared now and then, they were common, with many in private hands.

Of what possible use would jet-downs be on Trantor, with all the human life of the world under domes, with low cloud ceilings all but perpetual—except for a few government vehicles designed for just this purpose, that of picking up a wanted person who had been lured above the domes?

Why not? Government forces could not enter the grounds of the University, but perhaps Seldon was no longer on the grounds. He was on top of the domes, which might be outside the jurisdiction of any local government. An Imperial vehicle might have every right to land on any part of the dome and question or remove any person found upon it. Hummin had not warned him of this, but perhaps he had merely not thought of doing so.

The jet-down was even closer now, nosing about like a blind beast sniffing out its prey. Would it occur to them to search this