not one showed any sign of recognition or recovery.

But the real horror was on the other side of the field. Here were the
healthy ones, the uninfected ones who had received preventative
inoculations. A few hours before they had been left standing in quiet,
happy groups, talking among themselves, laughing and joking....

But now they weren't talking any more. They stared across at the doctors
with slack faces and dazed eyes, their feet shuffling aimlessly in the
dust. All were alive, but only half-alive. The intelligence and
alertness were gone from their faces; they were like the empty shells of
the creatures they had been a few hours before, indistinguishable from
the infected creatures in the other compound.

Jack turned to the Bruckian spokesman in alarm. "What's happened here?"
he asked. "What's become of the ones we inoculated? Where have you taken
them?"

The spokesman shrank back as though afraid Jack might reach out to touch
him. "Taken them!" he cried. "We have moved none of them! Those are the
ones you poisoned with your needles. What have you done to make them
like this?"

"It--it must be some sort of temporary reaction to the injection," Jack
faltered. "There was nothing that we used that could possibly have given
them the disease, we only used a substance to help them fight it off."

The Bruckian was shaking his fist angrily. "It's no reaction, it is the
plague itself! What kind of evil are you doing? You came here to help
us, and instead you bring us more misery. Do we not have enough of that
to please you?"

Swiftly the doctors began examining the patients in both enclosures, and
on each side they found the same picture. One by one they checked the
ones that had previously been untouched by the plague, and found only
the sagging jaws and idiot stares.

"There's no sense examining every one," Tiger said finally. "They're all
the same, every one."

"But this is impossible," Jack said, glancing apprehensively at the
growing mob of angry Bruckians outside the stockades. "What could have
happened? What have we done?"

"I don't know," Tiger said. "But whatever we've done has turned into a
boomerang. We knew that the antibody might not work, and the disease
might just go right ahead, but we didn't anticipate anything like this."

"Maybe some foreign protein got into the batch," Dal said.

Tiger shook his head. "It wouldn't behave like _this_. And we were
careful getting it ready. All we've done wa