“You see,” he said at last, “Number D-530 is building the Integral and I am sure the operation would interfere.⁠ ⁠…”

“Ah-h!” grumbled the other and stamped back into his room.

We remained alone. The paper-like hand was put lightly and caressingly upon mine, the profile-like face came nearer and he said in a very low voice: “I shall tell you a secret. You are not the only one. My colleague is right when he speaks of an epidemic. Try to remember, have you not noticed yourself, someone with something similar, very similar, identical?”

He looked at me closely. What was he alluding to? To whom?⁠ ⁠… Is it possible?⁠ ⁠…

“Listen,” I jumped up from my seat. But he had already changed the subject. In a loud metallic tone: