“How do you know?”

Roger was silent. Like Grover he hated the idea; but Potts had been free, supposedly resting. He might have been around. If anybody could know ways to get in—oh, it was not thinkable, though!

Much more Roger preferred to mistrust the electricians, or the bio-chemist.

On his way back he stopped at home to get the record carrying the “fire” and crackles. He would need a fresh record for that night.

With his package he returned to the laboratory. Everything was quiet, there. The men, in their activities, were sober but busy. Zendt greeted Roger.

“How is Astrovox?”

Roger told him. It was suspicious, the young cousin decided, that Zendt was so anxious. Less so, it seemed, about Doctor Ryder. He made no inquiry, though Roger, coming in, had called up the hospital to learn that the man was out of danger due to the prompt action of the interne at the laboratory. He must be quiet, for ten days or, at least, for a week, Roger had been told.

“Astrovox,” he told Zendt, “is unable to say anything, and they don’t expect anything else for days.”

That, he hoped, would “spike” any intentions the man might have to harm the old astrologer. Not wishing to say more he hurried to the dark-room, quickly put the waiting films in a time-and-temperature regulated bath and went out of the place for the eighteen minutes that would elapse during development. He busied himself clearing out the waiting requisitions for minor needs from the stockroom, tested the glass used by the doctor with no result, and then put the films in hypo. for fifteen minutes, staying in the open rooms during fixing period and washing afterward. He was not going to be caught in that dark-room, with Grover and Potts away and some stalking menace quite possibly still abroad.

His list was still in the file, he made certain. He had thought that it might have been taken; but he realized that whatever was on the paper was also in his head, and that was why he was endangered.