The phone rang again. "Yeah, Chief?"

"Schnell, Wood's just arrived. What shall I tell him?"

"Don't bother. He knows it all."

"Schnell, granting that you are right, why should he show his hand when he knows—or could easily find out—that the time-lock setting mechanism is on your side of that vault door?"

"Sure it is," I replied. "But it's covered by a sheet of five-ply safety glass."

"Use your revolver!"

"Chief, reprimand me for a violation of regulations if you must, but let me point out that only an idiot would wear a gun when he's pitting himself against a Psi-man."

"Got everything figured out, haven't you, Schnell?"

"Chief," I said, "this affair started in a sealed room, and now it's going to end in one."

I yanked on the telephone and pulled it out of its connection block, snapping that link of communication. Then, to satisfy Edward Hazlett Wood, I hurled the instrument as hard as I could against the safety glass. The telephone bounced as if I had thrown it against six solid feet of battleship plate armor.