1. The Deerstalker — Watson never describes Holmes as wearing a deerstalker. He talks about top hats, cloth hats, and caps with ear–flaps, but never does he use the word deerstalker. You can thank illustrator Sidney Paget for that iconic Holmesian symbol and actors like Basil Rathbone for solidifying the image into our collective memory.
2. The Calabash Pipe — The moment you see a Calabash pipe, you immediately get an image of Sherlock Holmes puffing away as he stands at a crime scene or sits in his favorite chair. While Watson does talk about three of Holmes’ pipes — briar, clay and cherry — the Calabash variety is never mentioned. You can thank stage actor William Gillette (one of the first to portray the detective) for this prop. Evidently it was easier to balance and more visually striking from a stage.
3. “Elementary, My Dear Watson” — One of the most quoted non–quotes ever. Yes, Holmes says “elementary” or “my dear Waston” but never does he utter the two as a single phrase.
4. Moriarty is Holmes’ Arch–Nemesis — Well… that depends on your definition of arch–nemesis. Moriarty only appears in one story, The Adventure of the Final Problem, in which he and Holmes go over the Reichenbach Falls. He’s mentioned in the story immediately preceding Final Problem in order to set up his character and in 5 more after Doyle brought Sherlock back from the grave, which means there are at least 50 stories and 4 novels where he is never discussed. Essentially, it appears that Moriarty simply came into existence so Doyle could kill off his popular character. Yes, Holmes calls him the “Napoleon of Crime” (which I still find odd wording and have my own theories around) and says that he’s like a spider that sits in the middle of a large web, so you could speculate that everyone Holmes comes up against is an agent of Moriarty’s but that would be mere speculation. I’m not arguing either way, I’m just saying…
5. Sherrinford Holmes — This alleged brother appears in Sherlock Holmes of Baker Street by William S. Baring–Gould. There are many things Baring–Gould alleges in this ‘biography’ but my favorite is inventing a brother Holmes never mentions in the stories. Holmes mentions his parents, older brother Mycroft, and even a grandmother, so it’s a mystery why Baring–Gould felt the need to invent another brother, though some speculate it was to free Mycroft and Sherlock from having to take over managing the family’s house, freeing them to move to London and run a shadow government and create the art of deduction.
6. Sherlock’s birthday is January 6th — Based solely on the fact that he mentions Twelfth Night twice in the stories and that The Valley of Fear starts on January 7th with him appearing to be especially cranky, which proponents of the date argue to mean he was hung over from celebrating his birthday.
7. Sherlock’s birth year is 1854 — There are many reasons for this date, but one that most point to is the fact that Watson mentions Holmes looking like a man of 60 years in His Last Bow. Counting backwards from the date when that story takes place, 1854 seems to be the logical choice. However, some argue that Watson says he ‘appeared’ to be, not ‘he was,’ so this date is still a topic for some debate.

This could go on and on with all the fun theories that have developed over the years (e.g., Holmes and Moriarty are brothers, Moriarty was Holmes’ math professor, Holmes is Jack the Ripper, etc.) but it’s a rabbit hole we might never crawl out of.

What about you other Holmes fans? What are some of your favorite myths and speculations about the Great Detective? I’m always eager to discover another item of Sherlock apocrypha I haven’t yet been clued into! Amaze me with the special knowledge only true fans possess!