Here's why:
* No official illustrations: Sir Arthur Conan Doyle didn't provide official illustrations for his stories.
* Varying interpretations: Many artists have depicted the characters over the years, resulting in diverse interpretations of their appearances.
* No definitive source: There's no single, universally recognized source for accurate sketches of all the characters.
However, you can find various resources that offer visual representations:
* The Illustrated Sherlock Holmes: This collection of stories includes illustrations by Sidney Paget, who was commissioned by The Strand Magazine to create the first visual representations of Holmes and Watson.
* Modern interpretations: Many illustrators and graphic novel artists have their own takes on the characters, offering different visual styles and interpretations.
* Online resources: Websites like "The Sherlock Holmes Encyclopedia" offer a collection of images and depictions of various characters.
While you might not find one book with sketches of all the characters, you can find many resources that offer visual representations of the Sherlock Holmes universe.