"No, he did not speak. But, in a comparatively lucid moment, he summoned up the energy to make some marks on a piece of paper which his wife gave him."

"Well, those marks . . . ?"

"They were illegible, for the most part."

"For the most part? But the others?" asked Lupin, greedily. "The others?"

"There were, first, three perfectly distinct figures: an 8, a 1, and a 3. . . ."

"Yes, 813, I know . . . and next?"

"And next, there were some letters . . . several letters, of which all that can be made out for certain are a group of three followed, immediately after, by a group of two letters."

"'APO ON,' is that it?"

"Oh, so you know! . . ."

The lock was yielding; almost all the screws had been taken out. Lupin, suddenly alarmed at the thought of being interrupted, asked: