The old man smiled ruefully.

“Yes. I knew that such a criticism would spur him to a maximum effort. The fact is, Drukker is on the track of something revolutionary. He has already worked out some very interesting theorems. . . . But I’m sure this isn’t what you gentlemen came here to discuss. What can I do for you, Markham? Or, perhaps you came to give me news.”

“Unfortunately we have no news. We have come to solicit aid again. . . .” Markham hesitated as if uncertain how to proceed; and Vance assumed the rôle of questioner.

“The situation has changed somewhat since we were here yesterday. One or two new matters have arisen, and there is a possibility that our investigation would be facilitated if we knew the exact movements of the members of your household last night. These movements, in fact, may have influenced certain factors in the case.”

The professor lifted his head in some surprise, but made no comment. He said merely: “That information is very easily given. To what members do you refer?”

“To no member specifically,” Vance hastened to assure him.

“Well, let me see. . . .” He took out his old meerschaum pipe and began filling it. “Belle and Sigurd and I had dinner alone at six o’clock. At half past seven Drukker dropped in, and a few minutes later Pardee called. Then at eight Sigurd and Belle went to the theatre, and at half past ten Drukker and Pardee went away. I myself turned in shortly after eleven, after locking up the house—I’d let Pyne and Beedle go to bed early.—And that’s about all I can tell you.”

“Do I understand that Miss Dillard and Mr. Arnesson went to the theatre together?”

“Yes. Sigurd rarely patronizes the theatre, but whenever he does he takes Belle along. He attends Ibsen’s plays, for the most part. He’s a devout disciple of Ibsen’s, by the way. His American upbringing hasn’t in the least tempered his enthusiasm for things Norwegian. At heart he’s quite loyal to his native country. He’s as well grounded in Norwegian literature as any professor at the University of Oslo; and the only music he really cares for is Grieg’s. When he goes to concerts or the theatre you’re pretty sure to find that the programs are liberally Norwegian.”

“It was an Ibsen play, then, he attended last night?”