“It was proved that he was suffering from some sort of heart trouble,” said Fairhurst. “Everybody seemed to know that—but then, for all I know, Arnell may also have had a weak heart.”

Shelley nodded. “He had,” he said briefly.

“He was apparently handling a heavy book of some sort, and he just collapsed and died. They brought in a verdict of death from natural causes.”

“And that,” said Shelley, “was that.”

“As far,” added Henry cautiously, “as we know at the present moment.”

“Yes,” said Shelley, and held out his hand to the little man. “Thank you very much for your information, Mr. Fairhurst, which I hope will be of some use to us. I will notify you when the inquest takes place, and what you will probably be asked there.”

“But, my dear Inspector,” protested Henry, “am I to know no more about this? I…I have given you some most important information, I…I have given you a hint which may be the point deciding the whole case. Am I to know nothing about what is done in the way of acting on this information?”

Shelley smiled. “The papers, my dear Mr. Fairhurst,” he said, “have a habit of reporting criminal cases in some fullness. And if your information is really important I might even be able to get you a seat at the Old Bailey for the trial.”

“But until then,” Henry began.

“Until then,” Shelley continued, “I fear that we cannot disclose any of our information, even to you, my dear Mr. Fairhurst.”

And with that Henry Fairhurst had perforce to be content.

He would, however, have been pleased if he could have seen the flurry of activity into which his story plunged Scotland Yard immediately after his departure.

Shelley rang bells and spoke into telephones. He visited various departments and talked to many people. Finally he sent for a certain gentleman at Scotland Yard who is known as the memory of the Yard, for his was an encyclopædic knowledge of all mysterious characters, all criminal cases, all sudden deaths within recent years. He was, in fact, a walking dictionary of crime.

“Look here, Mac,” said Shelley, when he arrived, “can you remember anything about the death of a fellow called Professor Wilkinson of Northfield University—happened six months or so back?”

Mac thought for a minute or so. “I’ll no say that I can remember all about yon fella,” he admitted, “but I can tell ye a bit aboot him.”

“Good,” said Shelley. “Carry on.”

“Died in Reading Room of British Museum,” said Mac, speaking in a sharp, jerky manner, almost as if reading a series of notes from a page. “Age 55. Height…”

“Don’t bother about measurements and so on,” said Shelley. “I can look them up at leisure. I want the facts about his death, verdict at the inquest, medical details, and all that sort of thing.”