“Thing is,” the old man continued, “far as I know, they were busy on the continent while this was following you in Britain. So even if he only devoted a little attention to it, using the machine across such a long distance, over that length of time, would have cost enormous mental energy. The machine would have been growing weak by now, in any case. They need, ah, topping up every now and then. Could you give me the spring-heels, Alex?”

Fascinated by the old man’s account, Alex had almost forgotten where they were perched. Moving with care, he unfastened the apparatus and handed it over to his grandfather, who began strapping it to his own feet. When the old man straightened again, he looked bleak.

“They know where we are. And they know we know. We have to assume they’ll be coming after us—” He stopped as the branch emitted an unmistakable crack. “Ah. Probably not a good idea to hang around up here, Alex.” He held out the rope. “Think you can shimmy down?”

Alex considered the drop doubtfully. The branch splintered again and shuddered alarmingly. His grandfather raised his eyebrows. Alex swung down, starting to lower himself.

“Good man. Probably best to take as much weight off this branch as possible. So I’ll see you down there.”

Alex felt the trembling relief of the branch through the rope as the old man jumped off and went plummeting past him. He shinned down as fast as he could, the rope slick with rain.

“That’s the style, Alex,” his grandfather called up from below. “Keep it up.”

His hands were raw, his biceps trembled, his mind reeled, and the branch above kept shivering. Pausing for an upward glance, Alex was disappointed to see how close it still was. As he watched, the branch snapped from the tree. Suddenly, he was falling, fast.

Something springing up just as fast slammed into him. He had a jumbled awareness of being wrapped in his grandfather’s arms. Then they were hitting damp green ground, hard. They tumbled forward in a heap together, then spilled apart.

Alex ended on his back, panting. He lay looking up. The slow gray sky framed by trees.

“You know, as first lessons in jumping with spring-heels go,” his grandfather said from somewhere nearby, “could’ve been worse.”

Alex felt rain on his face, tasted grass in his mouth. He heard sudden laughter. It took him a moment to recognize it as his own.

XIII.

UP THE HILL

After they checked there was no damage, they headed back to the car. Alex was about to get in when his grandfather stopped him.

“Just been thinking. If the flier got close enough to take a cutting from your clothes, it could have got close enough to plant something else.”