"He didn't come from Dettra, our home planet. Fashions are different on different worlds. His foot-wear was like a style we had on Dettra four years back, and his body-clothing has fasteners we don't use." Murgatroyd saw Calhoun and rushed to him, embracing his legs with enthusiasm and chattering shrilly of his relief at finding the man he knew. The skeletonlike plague-victims stared at him. "This," said Calhoun with infinite relief, "is Murgatroyd. He's had the plague and is over it. So now we'll get you people cured. I wish I had better light!" He counted Murgatroyd's breathing and listened to his heart. Murgatroyd was in that state of boisterous good health which is normal in any lower animal, but amounts to genius in a _tormal_. Calhoun regarded him with satisfaction. "All right!" he said. "Come along!" * * * * * He plucked a brand of burning resinous stuff from the campfire. He handed it to the gaunt young man and led the way. Murgatroyd ambled complacently after him. Calhoun stopped under one of the unoccupied shelters and got out his lab kit. He bent over Murgatroyd. What he did, did not hurt. When he stood up, he squinted at the red fluid in the instrument he'd used. "About fifteen CCs," he observed. "This is strictly emergency stuff I'm doing now. But I'd say that there's an emergency." The gaunt young man said: "I'd say you've doomed yourself. The incubation-period seems to be about six days. It took that long to develop among the doctors we had in the office staff." Calhoun opened a compartment of the kit, whose minuscule test tubes and pipettes gleamed in the torchlight. He absorbedly transferred the reddish fluid to a miniature filter-barrel, piercing a self-healing plastic cover to do so. He said: "You're pre-med? The way you talk--" "I was an interne," said Kim. "Now I'm pre-corpse." "I doubt that last," said Calhoun. "But I wish I had some distilled water--This is anticoagulant." He added the trace of a drop to the sealed, ruddy fluid. He shook the whole filter to agitate it. The instrument was hardly larger than his thumb. "Now a clumper--" He added a minute quantity of a second substance from an almost microscopic ampule. He shook the filter again. "You can guess what I'm doing. With a decent lab I'd get the structure and formula of the antibody Murgatroyd has so obligingly turned out for us. We'd set to work to synthesize it. In twenty hours, lab time, we ought to have it coming out of the reaction-flasks in quantity. But there is no lab."