Hemingway's shrewd gaze was fixed on his face. "You don't pass up many chances of annoying your uncle, do you, sir?"
"None, I hope," said Stephen coolly. "What makes you do it, sir, if I may ask?"
"Mutual antipathy."
"Mutual?" repeated Hemingway, lifting an eyebrow.
"Did I say mutual? A slip of the tongue."
Hemingway nodded, as though fully satisfied with this explanation. Stephen turned to go back into the drawing-room, but before he reached the door it opened, and Maud came out.
Her small mouth was folded closely, and she looked at Stephen with a stony expression in her eyes. He said: "I was coming to find you, Aunt. Inspector Hemingway advises you to enquire at your library for the name of the author of that book."
Maud's countenance relaxed a little, and the glance she cast at Hemingway was almost one of approval. "I must say that is a very sensible idea," she said. "But I still consider that the person who destroyed the book ought to own up. It was a very shabby trick. I should not have thought it of anyone at Lexham, even of you, Stephen."
"My good aunt, rid your mind of this obsession!" he said wearily. "Why should I have burnt it?"
Joseph told me that you said -"
Joseph told you!" he exclaimed, his brow growing thunderous. "I've no doubt! You will probably find that he burned the book himself for the pleasure of casting a fresh aspersion on to me!"
Maud seemed quite unresentful of this accusation. She said mildly: "I'm sure I don't know why he should do that, Stephen."
He gave a short laugh, and strode away in the direction of the billiard-room.
The Inspector watched him go, a thoughtful look in his eyes. As Maud continued her progress towards the stairs, he turned to look at her, saying: "Very unfortunate the way young Mr. Herriard seems to have his knife into your husband, madam. And his uncle so fond of him!"
But Maud was not to be drawn into discussion. She met the Inspector's look with a blank stare, and said in her flattest voice: "Yes."
He made no further effort to detain her, but went to find his Sergeant. "They were Joseph's finger-prints," he informed this worthy.
The Sergeant's lips formed a soundless whistle. "That does look fishy, sir," he admitted. "Very fishy indeed. But unless you can break down his alibi -"
"Forget it!" said Hemingway. "What have I missed? That's what I want to know."
The Sergeant scratched his head, "I lay awake half last night, trying to spot something," he said. "But I'm blessed if I could, I don't see what you can have missed."
"Of course you don't! If you could see it, I'd have seen it for myself, long ago!" Hemingway said irritably. "I've got a feeling the whole time that it's right under my nose, too, which is enough to make a saint swear. The trouble is I'm getting distracted, what with all the engagements being made and broken off, and Mrs. Herriard worrying me to find out who burned her ruddy Empress, and I don't know what beside. What I need is a bit of peace and quiet. Then I might be able to think."
The Sergeant hid a smile behind his hand. "Mrs. Herriard been at you again, sir?" he asked sympathetically.
"Not to mention young Stephen. I did think he'd more sense. Anyone would think I'd nothing better to do than to look for missing property!"
"Who was this Empress anyway?" asked the Sergeant.
"How should I know? Look here, if you're going to start badgering me about her, I may as well book myself a nice room in a mental home, because I'll need it. I got hold of you to talk over a murder, not to have a chat about a lot of foreign royalties. What would you say was a predominating factor in this case?"
The Sergeant could not resist this invitation. "Something that keeps on cropping up, sir? Well, I don't quite like to say."
"Why the devil not?" demanded Hemingway. "What is it?"
,Well, sir - the Empress!" said the Sergeant apologetically.
"Now, look here, my lad," Hemingway began, in an awful tone, "if you think this is the time to be cracking silly jokes-" He broke off suddenly, and his brows snapped together. "You're right!" he said. "By God, you are right!"
"I didn't mean it seriously, sir," the Sergeant said surprised. "It was just a silly joke, like you said."
"Perhaps it wasn't quite such a silly joke," Henmngway said. "Come to think of it, there is something queer about that book. Why did anyone want to burn it?"
"You said yourself, sir, you didn't blame anyone for getting rid of it, the way the old lady would keep on talking about it."
"You want to cure yourself of this ridiculous habit you've got into of remembering all the things I say which it would do you more good to forget," said Hemingway. "The only member of this outfit who might have pitched the book into the incinerator because he was tired of hearing about it is young Herriard, and he didn't do it."
"How do you know that, sir?"
"He said he didn't - that's how I know it."
"Seems to me you've only got his word for it," objected the Sergeant.
"Thanks," Hemingway said bitterly. "I may not be much good as a detective - in fact, I'm beginning to think I'm lousy - but every now and then I do know when a chap's lying and when he's speaking the truth. Stephen didn't burn that book, and it's no use trying to get me to believe that it was thrown into the incinerator by mistake, because that's a tale I never did believe, and never shall. Someone tried to get rid of that book, for some other reason than the one Stephen would have had, if he'd done it." His countenance suddenly assumed a rapt expression the Sergeant knew well. He shot out a finger. "Now, Joseph doesn't want the old lady to get hold of another copy, which is why his loving nephew Stephen's out to help her to do so. My lad, I believe we're on to something!"
"You may be, sir, but I'm damned if I am!" said the Sergeant. "I mean, what can a book about some Empress or other have to do with Nathaniel Herriard's death? It doesn't make sense!"
"Look here!" Hemingway said. "Who was this Empress?"
"That's what I asked you, sir, and you ticked me off properly for wasting your time."
"Elizabeth. That was the name," Hemingway said, quite unheeding. "She had a son who went and committed suicide at some hunting-lodge, with a girl he wanted to marry, and couldn't. I know that, because Mrs. Herriard told me that bit."
"Do you mean that that might have given the murderer some idea how to kill Nathaniel?" asked the Sergeant.
"That, or something else in the book. Something the old lady hadn't got to, is my guess. Wait a bit! Didn't some foreign royalty get murdered in Switzerland, or some place, once?"
"When would that be?" said the Sergeant. ""They're always getting themselves bumped off, these foreign royalties," he added disparagingly.
"It was some time in the last century, I think. What I want is an encyclopedia."
"Well, there's sure to be one in the library here, isn't there?" suggested the Sergeant.
"That's what I'm hoping," Hemingway said. "And I've only got to find the volume I want missing to be dead sure I'm on to something!"
There was no one in the library when they entered it a few minutes later, and the Inspector was gratified to discover a handsomely bound encyclopedia on one of the bookshelves which lined the walls of the room. The required volume was not missing, and after flicking over a great many pages devoted to the lives of all the Elizabeths in whom he had no interest, and whose claims to fame he was strongly inclined to resent, the Inspector at length came upon Elizabeth, Empress of Austria and Queen of Hungary, born at Munich, December 24th, 1837; assassinated September 10th, 1898, at Geneva.
"Assassinated!" ejaculated the Sergeant, reading the entry over his superior's shoulder.
"Don't breathe down my neck!" said Hemingway, and carried the volume over to the window.
The Sergeant watched him flick over some more pages, run a finger down a column, and then begin to read intently. The expression on his face changed slowly from one of expectant curiosity to one of almost spellbound surprise. The Sergeant hardly knew how to contain his soul in patience, but he knew better than to intrude upon his chief's absorption, and he waited anxiously for the reading to come to an end.