"What is it, George?" she asked anxiously. "Some of the women have slight fever, but it's going down. None of the fellows have any--but their white count is way up, their red count is way down, and they look sick to me." She approached St. Clair. His usually ruddy cheeks were pale, his pulse was light and too fast, and his skin felt clammy. "How's the headache? Did the Nucleocat treatment help?" "I feel worse, if anything." "Better set up beds," she told George. "Get everyone back into the clinic." "We're doing that," George assured her. "That's what Hal is doing." She went back to the laboratory. Max was pacing up and down, absently running his hands through his black hair until it stood straight up. He stopped when he saw her face, and scowled thoughtfully. "They are still sick?" It was more a statement than a question. She nodded. "The Cureall didn't cure this time," he muttered. "That leaves it up to us. We have melting sickness and according to Pat and the hamsters, that leaves us less than a day to find out what it is and learn how to stop it." Suddenly an idea for another test struck him and he moved to the work table to set it up. He worked rapidly, with an occasional uncoordinated movement betraying his usual efficiency. It was strange to see Max troubled and afraid. She put on a laboratory smock and began to work. She worked in silence. The mechanicals had failed. Hal and George Barton were busy staving off death from the weaker cases and trying to gain time for Max and her to work. The problem of the plague had to be solved by the two of them alone. It was in their hands. Another test, no results. Another test, no results. Max's hands were shaking and he stopped a moment to take stimulants. She went into the ward for a moment, found Bess and warned her quietly to tell the other women to be ready to take over if the men became too sick to go on. "But tell them calmly. We don't want to frighten the men." She lingered in the ward long enough to see the word spread among the women in a widening wave of paler faces and compressed lips; then she went back to the laboratory. Another test. There was no sign of a micro-organism in anyone's blood, merely a growing horde of leucocytes and phagocytes, prowling as if mobilized to repel invasion. * * * * * Len Marlow was wheeled in unconscious, with Hal Barton's written comments and conclusions pinned to the blanket. "I don't feel so well myself," the assistant complained. "The air feels thick. I can't breathe." June saw that his lips were blue. "Oxygen short," she told Max. "Low red corpuscle count," Max answered. "Look into a drop and see what's going on. Use mine; I feel the same way he does." She took two drops of Max's blood. The count was low, falling too fast.