“Oh,” he said, rather nonplussed and vexed. Then as this remark sank in, his former manner returned to him. He eyed Alleyn nervously, blinked, and got to his feet.

“I am sorry. I become somewhat absorbed when my pet subject is under discussion.”

“I too have been absorbed,” Alleyn told him. “You must forgive me for staying so long. I may have to reconstruct the operation—perhaps if I do you will be very kind and help me by coming along?”

“I—yes, if it is necessary. It will be very distasteful.”

“I know. It may not be necessary, but if it is—”

“I shall do my part, certainly.”

“Right. I must bolt. This has been an unpropitious sort of introduction, Dr. Roberts, but I hope I may be allowed to renew our talk without prejudice some time. The average bloke’s ignorance of racial problems is deplorable.”

“It’s worse than that,” said Roberts crisply. “It’s lamentable—criminal. I should have thought in your profession it was essential to understand at least the rudiments of the hereditary problem. How can you expect—” He scolded on for some time. The servant looked in, cast up his eyes in pious resignation and waited. Roberts gave Alleyn his book. “It’s the soundest popular work on the subject, though I do not pretend to cover a fraction of the ground. You’d better come back here when you’ve read it.”

“I will. Thank you a thousand times,” murmured the inspector and made for the door. He waited until the servant had gone into the hall and then turned back.

“Look here,” he said quietly. “Can I take it you think the man committed suicide?”

Again Roberts turned into a rather frightened little man.

“I can’t say—I—I sincerely hope so. In view of his history, I think it’s quite possible—but, of course, the drug—hyoscine— it’s very unusual.” He stopped and seemed to think deeply for a moment. Then he gave Alleyn a very earnest and somehow pathetic look. “I hope very much indeed that it may be found to be suicide,” he said quietly. “The alternative is quite unthinkable. It would cast the most terrible slur conceivable upon a profession of which I am an insignificant unit, but which I deeply revere. I would hold myself in part responsible. Self-interest is at the bottom of most motives, they say, but something more than self-interest, I think, prompts me to beg most earnestly that you explore the possibility of suicide to its utmost limit. I have kept you too long. Good night, Inspector Alleyn.”

“Good night, Dr. Roberts.”