St. Clair, he discovered that Mr. St. Clair had cut himself earlier that day on the hand. He then said that once he saw the letter with the dirty thumb print that was dated after the disappearance he knew that the evidence pointed more to the beggar and St. Clair having a closer relationship then expected. St. Clair admitted that he had indeed been acting the role of Hugh Boone for many years now. He said that he went undercover as a beggar once in order to write an article on beggars and realized that a lot of money could be made. He started doing it all the time without his wife and kids being aware of it and made a lot more money. He explained that the reason he did not want his wife to see him was because he was ashamed. He said that she spotted him as he was changing back to his regular clothes and he knew she would have questions. He said that he told the doorman to hold her downstairs until he could put the full disguise back on and explain later, By then the police had gotten involved and it was to late to turn back.Sherlock Holmes discovered the true reason that Neville St. Clair disappeared by using inductive reasoning. He used the clue of the letter, the blood and the cut to discover the true identity of Hugh Boone. ...
