A moment later he found himself in a narrow passageway, with rocks on one side and a heavy wooden partition on the other. Through a slit in the partition a faint light was streaming.

Adam Adams tiptoed his way to the slit and looked through. Beyond he made out the printing room of the counterfeiting plant. Only one man was present, the big-boned fellow known as Number Four. He was seated on the corner of a rude table, idly tearing some paper into strips, and evidently thinking deeply.

As the detective was about to move on, another person entered the printing room.

"Did they get him?" asked Number Four eagerly.

"Yes," was the short reply.

"Where was he?"

"You'd never guess."

"At the river?"

"No; in the vault."

"What! How did he get there?"