“The only unofficial consulting detective,” he answered. “I am the last and highest court of appeal in detection. When Gregson, or Lestrade, or Athelney Jones are out of their depths -which, by the way, is their normal state - the matter is laid before me. I examine the data, as an expert, and pronounce a specialist’s opinion. I claim no credit in such cases. My name figures in no newspaper. The work itself, the pleasure of finding a field for my peculiar powers, is my highest reward. But you have yourself had some experience of my methods of work in the Jefferson Hope case.”

“Yes, indeed,” said I cordially. “I was never so struck by anything in my life. I even embodied it in a small brochure, with the somewhat fantastic title of ‘A Study in Scarlet.’ ”

He shook his head sadly.

“I glanced over it,” said he. “Honestly, I cannot congratulate you upon it. Detection is, or ought to be, an exact science and should be treated in the same cold and unemotional manner. You have attempted to tinge it with romanticism, which produces much the same effect as if you worked a love-story or an elopement into the fifth proposition of Euclid.”

“But the romance was there,” I remonstrated. “I could not tamper with the facts.”

“Some facts should be suppressed, or, at least, a just sense of proportion should be observed in treating them. The only point in the case which deserved mention was the curious analytical reasoning from effects to causes, by which I succeeded in unravelling it.”

I was annoyed at this criticism of a work which had been specially designed to please him. I confess, too, that I was irritated by the egotism which seemed to demand that every line of my pamphlet should be devoted to his own special doings. More than once during the years that I had lived with him in Baker Street I had observed that a small vanity underlay my companion’s quiet and didactic manner. I made no remark, however, but sat nursing my wounded leg. I had had a Jezail bullet through it some time before, and though it did not prevent me from walking it ached wearily at every change of the weather.

“My practice has extended recently to the Continent,” said Holmes after a while, filling up his old brier-root pipe. “I was consulted last week by Francois le Villard, who, as you probably know, has come rather to the front lately in the French detective service. He has all the Celtic power of quick intuition, but he is deficient in the wide range of exact knowledge which is essential to the higher developments of his art. The case was concerned with a will and possessed some features of interest. I was able to refer him to two parallel cases, the one at Riga in 1857, and the other at St. Louis in 1871, which have suggested to him the true solution. Here is the letter which I had this morning acknowledging my assistance.”

He tossed over, as he spoke, a crumpled sheet of foreign notepaper. I glanced my eyes down it, catching a profusion of notes of admiration, with stray magnifiques, coup-de-maîtres and tours-de-force, all testifying to the ardent admiration of the Frenchman.

“He speaks as a pupil to his master,” said I.

“Oh, he rates my assistance too highly,” said Sherlock Holmes lightly. “He has considerable gifts himself. He possesses two out of the three qualities necessary for the ideal detective. He has the power of observation and that of deduction. He is only wanting in knowledge, and that may come in time. He is now translating my small works into French.”

“Your works?”