to the royal family of Scandinavia, and to the French republic, have left me in such a position that I could continue to live in the quiet fashion which is most congenial to me, and to concentrate my attention upon my chemical researches. But I could not rest, Watson, I could not sit quiet in my chair, if I thought that such a man as Professor Moriarty were walking the streets of London unchallenged."
"What has he done, then?"
"His career has been an extraordinary one. He is a man of good birth and excellent education, endowed by nature with a phenomenal mathematical faculty. At the age of twenty-one he wrote a treatise upon the Binomial Theorem, which has had a European vogue. On the strength of it he won the Mathematical Chair at one of our smaller universities, and had, to all appearances, a most brilliant career before him. But the man had hereditary tendencies of the most diabolical kind. A criminal strain ran in his blood, which, instead of being modified, was increased and rendered infinitely more dangerous by his extraordinary mental powers. Dark rumors gathered round him in the university town, and eventually he was compelled to resign his chair and to come down to London, where he set up as an army coach. So much is known to the world, but what I am telling you now is what I have myself discovered.
"As you are aware, Watson, there is no one who knows the higher criminal world of London so well as I do. For years past I have continually been conscious of some power behind the malefactor, some deep organizing power which forever stands in the way of the law, and throws its shield over the wrong-doer. Again and again in cases of the most varying sorts—forgery cases, robberies, murders—I have felt the presence of this force, and I have deduced its action in many of those undiscovered crimes in which I have not been personally consulted. For years I have endeavored to break through the veil which shrouded it, and at last the time came when I seized my thread and followed it, until it led me, after a thousand
