"Did you ever trouble to see who called for them?"
"No."
The inspector looked surprised and a little shocked. "Why not?"
"Because I always keep faith. I had promised when he first wrote that I would not try to trace him."
"You think there is someone behind him?"
"I know there is."
"This professor that I've heard you mention?"
"Exactly!"
Inspector MacDonald smiled, and his eyelid quivered as he glanced towards me. "I won't conceal from you, Mr. Holmes, that we think in the C. I. D. that you have a wee bit of a bee in your bonnet over this professor. I made some inquiries myself about the matter. He seems to be a very respectable, learned, and talented sort of man."
"I'm glad you've got so far as to recognize the talent."
"Man, you can't but recognize it! After I heard your view I made it my business to see him. I had a chat with him on eclipses. How the talk got that way I canna think; but he had out a reflector lantern and a globe, and made it all clear in a minute. He lent me a book; but I don't mind saying that it was a bit above my head, though I had a good Aberdeen upbringing. He'd have made a grand meenister with his thin face and gray hair and solemn-like way of talking. When he put his hand on my shoulder as we were parting, it was like a father's blessing before you go out into the cold, cruel world."
Holmes chuckled and rubbed his hands. "Great!" he said. "Great! Tell me, Friend MacDonald, this pleasing and touching interview was, I suppose, in the professor's study?"
"That's so."
"A fine room, is it not?"
"Very fine—very handsome indeed, Mr. Holmes."
"You sat in front of his writing desk?"
"Just so."
"Sun in your eyes and his face in the shadow?"
"Well, it was evening; but I mind that the lamp was turned on my face."
"It would be. Did you happen to observe a picture over the professor's head?"
"I don't miss much, Mr. Holmes. Maybe I learned that from you. Yes, I saw the picture—a young woman with her head on her hands, peeping at you sideways."
"That painting was by Jean Baptiste Greuze."
The inspector endeavoured to look interested.
"Jean Baptiste Greuze," Holmes continued, joining his finger tips and leaning well back in his chair, "was a French artist who flourished between the years 1750 and 1800. I allude, of course to his working career. Modern criticism has more than indorsed the high opinion formed of him by his contemporaries."
The inspector's eyes grew abstracted. "Hadn't we better—" he said.
"We are doing so," Holmes interrupted. "All that I am saying has a very direct and vital bearing upon what you have called the Birlstone Mystery. In fact, it may in a sense be called the very centre of it."
MacDonald smiled feebly, and looked appealingly to me. "Your thoughts move a bit too quick for me, Mr. Holmes. You leave out a link or two, and I can't get over the gap. What in the whole wide world can be the connection between this dead painting man and the affair at Birlstone?"
"All knowledge comes useful to the detective," remarked Holmes. "Even the trivial fact that in the year 1865 a picture by Greuze entitled La Jeune Fille a l'Agneau fetched one million two hundred thousand francs—more than forty thousand pounds—at the Portalis sale may start a train of reflection in your mind."
It was clear that it did. The inspector looked honestly interested.
"I may remind you," Holmes continued, "that the professor's salary can be ascertained in several trustworthy books of reference. It is seven hundred a year."
"Then how could he buy—"
"Quite so! How could he?"
"Ay, that's remarkable," said the inspector thoughtfully. "Talk away, Mr. Holmes. I'm just loving it. It's fine!"
Holmes smiled. He was always warmed by genuine admiration—the characteristic of the real artist. "What about Birlstone?" he asked.
"We've time yet," said the inspector, glancing at his watch. "I've a cab at the door, and it won't take us twenty minutes to Victoria. But about this picture: I thought you told me once, Mr. Holmes, that you had never met Professor Moriarty."
"No, I never have."
"Then how do you know about his rooms?"
"Ah, that's another matter. I have been three times in his rooms, twice waiting for him under different pretexts and leaving before he came. Once—well, I can hardly tell about the once to an official detective. It was on the last occasion that I took the liberty of running over his papers—with the most unexpected results."
"You found something compromising?"
"Absolutely nothing. That was what amazed me. However, you have now seen the point of the picture. It shows him to be a very wealthy man. How did he acquire wealth? He is unmarried. His younger brother is a station master in the west of England. His chair is worth seven hundred a year. And he owns a Greuze."
"Well?"
"Surely the inference is plain."
"You mean that he has a great income and that he must earn it in an illegal fashion?"
"Exactly. Of course I have other reasons for thinking so—dozens of exiguous threads which lead vaguely up towards the centre of the web where the poisonous, motionless creature is lurking. I only mention the Greuze because it brings the matter within the range of your own observation."
"Well, Mr. Holmes, I admit that what you say is interesting: it's more than interesting—it's just wonderful. But let us have it a little clearer if you can. Is it forgery, coining, burglary—where does the money come from?"
"Have you ever read of Jonathan Wild?"
"Well, the name has a familiar sound. Someone in a novel, was he not? I don't take much stock of detectives in novels—chaps that do things and never let you see how they do them. That's just inspiration: not business."
"Jonathan Wild wasn't a detective, and he wasn't in a novel. He was a master criminal, and he lived last century—1750 or thereabouts."
"Then he's no use to me. I'm a practical man."
"Mr. Mac, the most practical thing that you ever did in your life would be to shut yourself up for three months and read twelve hours a day at the annals of crime. Everything comes in circles—even Professor Moriarty. Jonathan Wild was the hidden force of the London criminals, to whom he sold his brains and his organization on a fifteen per cent commission. The old wheel turns, and the same spoke comes up. It's all been done before, and will be again. I'll tell you one or two things about Moriarty which may interest you."
"You'll interest me, right enough."
"I happen to know who is the first link in his chain—a chain with this Napoleon-gone-wrong at one end, and a hundred broken fighting men, pickpockets, blackmailers, and card sharpers at the other, with every sort of crime in between. His chief of staff is Colonel Sebastian Moran, as aloof and guarded and inaccessible to the law as himself. What do you think he pays him?"
"I'd like to hear."
"Six thousand a year. That's paying for brains, you see—the American business principle. I learned that detail quite by chance. It's more than the Prime Minister gets. That gives you an idea of Moriarty's gains and of the scale on which he works. Another point: I made it my business to hunt down some of Moriarty's checks lately—just common innocent checks that he pays his household bills with. They were drawn on six different banks. Does that make any impression on your mind?"
"Queer, certainly! But what do you gather from it?"
"That