If he could only remember how they had made the wheelchair grow from him, perhaps he could figure out how to rid himself of it. But his memory was still so hazy, and every time he began to think back, he found himself remembering further than he meant to:

The road in the forest. The smell of pipe smoke. His father’s empty face. The blood in the snow.

This wasn’t helping. His hands were so sweaty. He just wanted to wipe them, just once against his coat. And to make matters worse, there seemed to be some grit in his mittens, sand or gravel, that had begun to cling to his sweaty fingers.

“Wait,” said Mammon. “Haven’t I seen that shop before?”

Swiftly, Yehuda Leib turned the wheelchair up a steep hill.

He had to concentrate.

He had to think.

The forest road. A donkey cart. Issur Frumkin.

Here was something useful: Issur had told him three ways to ward off demons.

What had they been?

“Ugh,” said Mammon. “Can’t you go any faster? We’re hardly moving at all.”

And it was true: Yehuda Leib was making barely any headway, and the heavy load in the wheelchair pressed backward painfully against his fingernails.

He had to think.

Three protections against the demons, Issur had said. What had they been?

Red thread—that had been one. If only his scarf hadn’t been torn from his neck…

But that wasn’t a useful thought.

What were the other two protections?

Cold metal. But even had Yehuda Leib carried any metal with him, how could he have accessed it with his hands bound up in the wheelchair?

No, there was no help there.

What was the third?

Cold metal, red thread…

“Come on, boy,” said Mammon. “Put forth a little effort!”

They had stalled, a raised cobble in the steep road presenting a nearly insuperable obstacle to Yehuda Leib and the fingernail wheelchair. Once, twice, he shoved against it, but he couldn’t pick up enough momentum.

“Don’t make me use the whip, boy.”

Yehuda Leib’s fingernails ached painfully with the weight of the wheelchair they had formed. Inside his mittens, the grit had begun to sting, abrading his fingers.

Why on earth had he put on these mittens?

“Move, boy! Move!”

With a great shove, Yehuda Leib forced the wheelchair up and over the cobble.

And the oddest thing happened.

Inside his right mitten, one of his fingernails—the third—snapped.

It was free. He could bend the finger alone. And when he did, he felt quite a bit more grit in his mitten than he had anticipated.

What was this in his mittens?

And in a rush of illumination, it all came flooding back:

Salt. The demons’ magic can’t pass beyond boundaries of salt.