On the roof were many doors, and to such a man as me there was no difficulty." "Go on," said Tarling again.
"I came down from floor to floor, always in darkness, but each floor I searched carefully, but found nothing but great bundles and packing-cases and long bars----" "Counters," corrected Tarling.
"Yes," nodded Ling Chu, "they are called counters.

And then at last I came to the floor where I had seen The Man." He paused.

"First I went to the great room where we had met him, and that was locked.

I opened it with a key, but it was in darkness, and I knew nobody was there.

Then I went along a passage very carefully, because there was a light at the other end, and I came to an office." "Empty, of course ?" "It was empty," said the Chinaman, "but a light was burning, and the desk cover was open.